Chapter 9
After Diagnosis: Rehabilitating Cardiac Patients
- After ppl exp a heart attack, angina, or other symptoms of CVD, they sometimes receive a referral to a cardiac rehab program to change their lifestyle and lower risk for a subsequent (and possibly even more serious) event - In addition to survival, the goals of cardiac rehab programs are to help patients deal w/ psychological reactions to their diagnosis, to return to normal activities as soon as possible, and to change to a healthier lifestyle - Patients recovering from heart disease often exp a variety of psych reactions, including depression, anxiety, anger, fear, guilt, and interpersonal conflict - Most common psych reaction to myocardial infarction is depression, which decreases adherence to medication and lifestyle changes, and increases the risk of death to 3.5 times that for non-depressed cardiac patients - Treating depression among cardiac patients is an important but difficult problem; two large-scale interventions sought to treat depression among cardiac patients thru use of antidepressant medications or cog beh therapy - Though these trials have some success in treating depression, the antidepressant intervention didn't improve survival - Cog beh intervention improved survival among Euro American men, but not among ethnic minority men or among women - Another common psych reaction related to depression is anxiety; a follow-up study of cardiac rehab patients showed that those who completed the rehab program continued to make progress not only in lowering their physiological risks but also in lowering their levels of anxiety and depression, and increasing their feelings of control - One common source of anxiety among heart patients and their spouses is the resumption of sexual activity; probably source of this anxiety is concern abt the elevation of heart rate during sex, esp during orgasm - H/e, sexual activity poses little threat to cardiac patients - Male CAD patients who take Viagra don't have an elevated risk of subsequent heart problems, but this drug may interact in dangerous ways w/ drugs for hypertension that such patients may be taking - Cardiac rehab programs usually include components to help patients stop smoking, eat a low-fat and low-cholesterol diet, control weight, moderate alcohol intake, learn to manage stress and hostility, and adhere to a prescribed medication regimen - Cardiac patients frequently participate in a graduated or structured exercise program in which they gradually increase their level of phys activity - Same lifestyle recommendations for avoiding a first CV event also apply to survivors of myocardial infarction, coronary artery bypass graft surgery, and stroke - Patients often encouraged to join a social support group, participate in health edu programs, and allow support from their primary caregiver - Some research indicated that cardiac patients rated such social support and being with others who shared the same problem as the most valuable aspects of the program - Dean Ornish and colleagues devised a comprehensive cardiac rehab program w/ diet, stress management, smoking cessation, and phys activity components in an effort to reverse heart patients' coronary artery damage - Adherence is a major problem with cardiac rehab programs in general; less than half of cardiac patients complete their rehab regimen - One factor that may influence adherence involves the physician, rather than the patient; many cardiologists fail to endorse rehab programs, which affects their patients' willingness to participate - Many patients also cite difficulties in finding time for and traveling to a clinic for rehab - Same factors that predict the development of CVD also predict failure to adhere to rehab; depression, being a smoker, being overweight, and having a high CV risk profile - Patients who are most in need of intervention may be least likely to adhere - When used as intended, many different rehab programs are effective, including brief interventions and at-home rehab programs - A meta-analysis of studies on the effectiveness of two components of cardiac rehab programs found that heart disease patients who followed a health edu and stress management program had a 34% reduction in cardiac mortality and a 29% reduction in recurrence of a heart attack - Exercise-based cardiac rehab programs are also effective in reducing cardiac mortality and heart attack recurrence - Exercise may present some risks for cardiac patients, but the benefits far outweigh the risks - A graded exercise program can enhance patients' self-efficacy for increasing levels of activity, as well as increase self-esteem and physical mobility - After a diagnosis of heart problems, exercise programs have 3 main goals: 1. Exercise can maintain or improve functional capacity 2. It can enhance a person's quality of life 3. It can help prevent recurrent heart attacks - Thus, cardiac rehab programs are an effective but underused strategy
Inherent Risk Factors
- Result from genetic/physical conditions that can't be readily modified - Though they can't be changed, ppl w/ these risk factors aren't necessarily destined to develop CVD - Identifying ppl w/ inherent risk factors enables these high-risk individuals to minimize their overall risk profile by controlling the things they can, such as hypertension, smoking, and diet - Inherent factors include: 1. Advancing age 1.a. Primary risk factor; as ppl become older, their risk for CV death rises sharply 1.b. Fig 9.8; for every 1-yr increase in age, both men and women more than double their chances of dying of CVD 2. Family history 2.a. Ppl w/ a history of CVD in their family are more likely to die of heart disease than those w/ no such history 2.b. Ppl w/ a parent who has suffered a heart attack are more likely to suffer a heart attack themselves 2.c. Familial risk is likely to occur through the action of many genes and their interactions w/ environmental factors in ppl's lives; genes cannot be altered by lifestyle changes 3. Gender 3.a. Though an inherent risk factor, many behaviors and social conditions are related to gender; differing risk for women and men may or may not be inherent 3.b. Men have a higher rate of death from CVD than women; discrepancy shows most prominently during the middle-age years -- after that age, the % of women's deaths due to CVD increases sharply 3.c. Larger number of older women than older men die of CVD; nonetheless, the RATE of death from CVD remains higher for men 3.d. Both physiology and lifestyle contribute; before menopause, women experience a lower rate of CVD than men 3.e. More recent focus on androgens, including the possibility that these hormones may involve both protections and risks for men and women 3.f. Lifestyle is responsible for much of the gender gap in the disease 3.g. Across world, men tend to exp a heart attack at an earlier age than women do, and this difference is explained by men's higher rates of unhealthy lifestyle factors during their younger years 3.h. Gender gap is particularly large in some countries 4. Ethnic background 4.a. African Americans have more than a 30% greater risk for CV death than European Americans, but Natic Americans, Asian Americans, and Hispanic Americans have lower rates 4.b. Increased risk for African Americans may be related to social, economic, or behavioral factors rather than to any bio basis, because the INTERHEART Study indicated the risk factors for heart disease are the same for ppl in countries around the world 4.c. Ethnic differences in heart disease are likely due to ethnic differences in levels of known risk factors 4.d. Strongest risk factor for African Americans is high BP, but psychosocial risks such as low income and low edu level also have major impact 4.e. Higher rates of cardiovascular death among African Americans may be due to their higher rate of hypertension; higher rate of hypertension may be partly due to greater cardiac reactivity, as a possible result of ongoing experiences of racial discrimination; even threats of discrimination can raise BP in African Americans 4.f. Tendency to react to stress/threats of stress with increase cardiac reactivity may arise from years of racial discrimination, discrimination most likely to be experienced by dark-skinned ppl 4.g. Dark-skinned African Americans were 11x more likely than light-skinned African Americans to exp frequent racial discrimination 4.h. These responses are classified as psychosocial risks that relate to ethnicity rather than as a risk that is inherent in ethnic differences
Blood Pressure
- When the heart pumps blood, the force must be substantial to power circulation for an entire cycle through the body and back to the heart - In a healthy CV system, pressure in the arteries isn't a problem bc of artery elasticity - In a CV system diseased by atherosclerosis and arteriosclerosis, the pressure of the blood in the arteries can produce serious consequences - Narrowing of the arteries that occurs in atherosclerosis and the loss of elasticity that characterizes arteriosclerosis both tend to raise BP; these disease processes make the cardiovascular system less capable of adapting to the demands of heavy exercise/stress - BP measurements are usually expressed by 2 numbers 1. First number represents systolic pressure, the pressure generated by the heart's contraction 2. Second number represents diastolic pressure, or the pressure experienced between contractions, reflecting the elasticity of the vessel walls 3. Both numbers are expressed in mm of mercury (Hg) bc original measurements of blood pressure were obtained by determining how high mercury would rise in a glass column by the pressure of blood in circulation - BP elevates through several mechanisms; some elevations are normal and even adaptive - Other elevations in BP are neither normal nor adaptive, but are symptoms of CV disease - Hypertension: abnormally high BP; this 'silent' illness is the best predictor of both heart attack and stroke, but can also cause eye damage and kidney failure - Fig 9.6 - Essential hypertension refers to a chronic elevation of BP, which has both genetic and environmental causes; affects 1/3 of ppl in the US and other developed countries 1. Strongly related to aging, but also to factors such as African American ancestry, weight, sodium intake, tobacco use, and lack of exercise - Table 9.1 - Hypertension doesn't have easily discernible symptoms, so ppl w/ hypertension can have dangerously elevated BP and remain completely unaware of their vulnerability to heart attack/stroke - In younger individuals, high diastolic pressure is most strongly related to CV risk, but in older individuals, elevated systolic pressure is a better predictor - Each 20mm Hg increase in systolic BP doubles the risk of CVD - Systolic pressure that exceeds 200mm Hg presents a danger of rupture in the arterial walls - Diastolic hypertension tends to result in vascular damage that may injure organs served by the affected vessels, most commonly the kidneys, liver, pancreas, brain, and retina - Because the underlying cause of essential hypertension is complex and not fully understood, no treatment exists that will remedy its basic cause - Treatment tends to be oriented toward drugs/changes in behavior and lifestyle that can lower BP - Health psychologists play an important role in encouraging such behaviors as controlling weight, maintaining a regular exercise program, and restricting sodium intake - Adherence to these behaviors is important for controlling BP; adherence to meds is notoriously poor
A Floss a Day May Keep Cardiovascular Disease Away
- Accumulating research draws surprising links b/w oral health and CV health - Periodontitis: inflammation of the tissues and bones that support the teeth; risk factor for CVD, independent of other established risk factors - Even a person's frequency of tooth brushing predicts their subsequent likelihood of CVD - Possible connections between oral and cardiovascular health: 1. Periodontitis increases the level of systemic inflammation in the body 2. Bacteria that cause dental plaque and periodontitis eventually settle on artery walls after they enter the bloodstream; such bacteria then become the target of an inflammatory response, making atherosclerosis more likely
Behavioral Factors -- Physical Activity
- Across the world, 2 factors consistently predict higher risk of heart attack: owning a car and owning a television, both reduce phys activity - Risks of inactivity apply to the entire lifespan - Sedentary lifestyle also contributes to the metabolic syndrome, the pattern of CVD risks that include overweight, abdominal fat, and blood glucose metabolism problems
Physiological Conditions -- Inflammation
- Atherosclerosis results in part from the body's natural inflammatory response - When an artery is injured/infected, white blood cells migrate toward and accumulate on the artery wall; when a person's diet is high in cholesterol, the 'diet' of these white blood cells is likewise high in cholesterol - Arterial plaques, the precursors to atherosclerosis, are simply accumulations of cholesterol-filled white blood cells - Inflammation influences not only the development of plaques but also their stability, making them more likely to rupture and cause a heart attack/stroke - Because chronic inflammation may raise risk for development of atherosclerosis, factors that produce chronic inflammation may also increase risk for CVD - Stress and depression are two factors that may contribute to inflammation and art 2 known risk factors for CVD - Inflammation processes account for some, but not all, of the association between depression and increased risk of CV mortality - Metabolic syndrome may also be related to inflammation, suggesting these conditions interact or have some common pathways for causing damage to the CV system - Any factor that reduces inflammation may reduce risk for CVD
What are the risk factors for CVD?
- Beginning w/ the Framingham study, researchers ID'd a number of CV risk factors: 1. Inherent risk 1.a. Advancing age, family history, gender and ethnicity 1.b. Not modifiable, but ppl w/ such risks can alter their other risks to lower their chances of developing heart disease 2. Physiological risks 2.a. Hypertension and high cholesterol; diet can play a role in controlling each of these 3. Behavioral and lifestyle risks 3.a. Smoking, a diet high in saturated fat and low in fiber/antioxidant vitamins, low phys activity level 4. Psychosocial risks 4.a. Low educational/income levels, lack of social support, persistently high levels of stress/anxiety/depression 4.b. Hostility and violent expression/suppression of anger elevate risk slightly
What behaviors allow people to lower their CV risks?
- Both before and after a diagnosis, ppl can use a variety of approaches to reduce their risks for CVD - Drugs, sodium restriction, and weight loss all can control hypertension - Drugs, diet, and exercise also can lower cholesterol levels - Lowering ratio of total cholesterol to HDL is probably a better idea, but that statin type of cholesterol-lowering drugs tends to lower LDL, which can also be beneficial - Ppl can learn to manage stress more effectively, enter therapy to improve depression, and learn to manage anger to avoid loud, quick outbursts and to express their frustrations in a soft, slow manner
Summary thus far
- CV system consists of the heart and blood vessels - Heart pumps blood to circulate throughout the body to supply it w/ oxygen and remove waste products - Coronary arteries supply blood to the heart itself, and when atherosclerosis affects these arteries, coronary, artery disease occurs - In this disease process, plaques form within the arteries, restricting blood supply to the heart muscle - Restriction can cause angina pectoris - Blocked coronary arteries can also lead to a myocardial infarction - When oxygen supply to brain is disrupted, stroke occurs; can affect any part of the brain and can vary in severity from minor to fatal - Hypertension is a predictor of both heart attack and stroke
Coronary Artery Disease (CAD)
- Refers to damage to the coronary arteries, typically through processes of atherosclerosis and arteriosclerosis - No clearly visible outward symptoms accompany the buildup of plaques in the coronary arteries - Can develop while a person remains totally unaware of its progress - Plaques narrow the arteries and restrict the supply of blood to the myocardium - Deposits of plaque may also rupture and form blood clots that can obstruct an artery; if it deprives the heart of oxygen, the heart won't function properly - Restriction of blood flow is called ischemia; likely cause of chest pain and shortness of breath symptoms
Physiological Conditions -- Serum Cholesterol Level
- Cholesterol is a waxy, fat-like substance that is essential for human life as a component of cell membranes - Serum or blood cholesterol is the lvl of cholesterol circulating through the bloodstream; this lvl is related to dietary cholesterol, or the amount of cholesterol in one's food - Dietary cholesterol comes from animal fats and oils but not from veggies/veggie products - Though essential for life, too much may contribute to the process of developing CVD - After a person eats cholesterol, the bloodstream transports it as part of the process of digestion - A measurement of the amt of cholesterol carried in the serum (the liquid, cell-free part of the blood) is typically expressed in mg of cholesterol per deciliters (dl) of serum - Total cholesterol in the bloodstream isn't the best predictor of CVD - Cholesterol circulates in the blood in several forms of 'lipoproteins', which can be distinguished by analyzing their density and function - Low-density lipoprotein (LDL) carries cholesterol from the liver to the cells of the body 1. Seems to promote atherosclerosis 2. Sometimes referred to as 'bad cholesterol' - High-density lipoprotein (HDL) carries cholesterol from the tissues back to the liver 1. Seems to offer some protection against CVD 2. Sometimes referred to as 'good cholesterol' - Framingham researchers found that LDL was positively related to CVD, whereas HDL was negatively related - Women's higher levels of HDL may be a partial explanation from the gender gap in heart disease - Total cholesterol (TC) is determined by adding the values for HDL, LDL, and 20% of very low-density lipoprotein (VLDL), also called triglycerides - A low ratio of total cholesterol to HDL is more desirable than a high ratio - Table 9.2 - Cholesterol is a stronger predictor of CV problems for young/middle-aged adults compared w/ older adults
Behavioral Factors -- Smoking
- Cigarette smoking is the leading beh risk factor for CV death in US, and a major contributor to deaths throughout the world - Smoking accounts for ~35% of the risk for heart attack worldwide, which translates into more than a million deaths per year - Ppl who currently smoke are 3x more likely to suffer a heart attack than ppl who never smoked; quitting smoking does reduce the risk - Risks of past smoking don't disappear completely, as a small risk for heart attack persists even 20yrs after a person quits - CV risks of tobacco remain even when smoke isn't inhaled, as the chewing tobacco also increases risk of heart attack - Secondhand smoke exposure to environmental tobacco smoke raises risk for CVD about 15%
The Cardiovascular System
- Consists of the heart, arteries, and veins - Heart is a muscle that, by contracting and relaxing, pumps blood throughout the body; essentially the center of a rapid-transit system that carries oxygen to body cells and removes CO2 and other wastes from cells - Under healthy conditions, the CV, respiratory, and digestive systems are integrated - Digestive system produces nutrients and the respiratory system furnishes oxygen, both of which circulate through the blood to various parts of the body - Endocrine system affects CV system by stimulating/depressing the rate of CV activity - Fig 9.1 - Blood route's entire circuit takes about 20sec when the body is at rest, but exertion speeds the process - Blood travels from right ventricle of heart to lungs, where hemoglobin saturates it w/ oxygen - From lungs, oxygenated blood travels back to left atrium of heart, then to left ventricle, and finally out to rest of body - Arteries carry oxygenated blood branch into vessels of smaller and smaller diameter, called arterioles, and finally terminate in tiny capillaries that connect arteries and veins - Oxygen diffuses out to body cells, and CO2 and other chemical wastes pass into blood for disposal - Blood that's been stripped of its oxygen returns to the heart by way of the system of veins, beginning with the tiny venules and ending with the two large veins that empty into the right atrium, the upper right chamber of the heart - CVD: general term that includes coronary artery disease, coronary heart disease, and stroke
Changing Rates of CVD
- Current mortality rate in US is lower than it was in 1920, however between 1920-2002, the death rates changed dramatically - Fig 9.7 - Currently, 34% of all deaths in the US are from CVD - In 1920, rate of deaths due to heart disease was similar for women and men; overall the rates of death from CVD remain similar, but the pattern of deaths began to differ when CVD rates began to rise - During middle of 20th century, men died from CVD at younger ages than women
The Ornish Program
- Dean Ornish and colleagues devised a comprehensive cardiac rehab program w/ diet, stress management, smoking cessation, and phys activity components in an effort to reverse heart patients' coronary artery damage - Though similar to the interventions that attempt to alter risk factors, this program was more comprehensive and imposed more stringent modifications, esp w/ regard to diet - Recommends that cardiac patients reduce their consumption of fat to only 10% of their total caloric intake, which necessitates a careful vegetarian diet w/ no added fats from oils, eggs, butter, or nuts - An eval of the program included a control group that received a typical cardiac rehab program along w/ the experimental group of participants on the Ornish program - Early research on the benefits painted a slightly more optimistic pic of its benefits than later research - After 1 year of the program, Ornish and colleagues found that 82% of patients in the treatment group showed a regression of plaques in coronary arteries - After 5yrs, program produced less artery blockage and fewer coronary events - Though a later study failed to confirm the reversal of arterial plaque, it did show that patients on the Ornish program decreased their risk factors to a greater extent than those in a standard cardiac rehab program and decreased their symptoms of angina substantially - Benefits in decreasing angina also appeared in another study, and other research confirms that dietary change can reverse arterial plaque - Main disadvantage of a program such as the Ornish plan is the difficulty of following such a stringent diet
Reasons for the Decline in Death Rates
- Decline in cardiac mortality in the US is due largely to two causes: 1. Improved emergency coronary care 2. Changes in risk factors for CVD - Beginning in the 1960s, many ppl in the US began to change their lifestyle; smoked less, became more aware of their BP, control serum cholesterol, watch their weight, and follow a regular exercise program - Publicity from 2 monumental research studies prompted these lifestyle changes 1. Framingham Heart study 1.a. Implicated cigarette smoking, high cholesterol, hypertension, a sedentary lifestyle, and obesity as risk factors in CVD 2. Surgeon General's report 2.a. Found a strong association b/w cigarette smoking and heart disease - Although these lifestyle changes closely parallel declining heart disease death rates, they offer no proof of a causal link b/w beh changes and the drip in CV mortality - During this same period, medical care and technology continued to improve, and many cardiac patients who in earlier years would have died were saved by better and faster treatment - About 47% of the decline in CHD was due to improvements in treatment and 44% to changes in risk factors - The declining rate of death is due about as much to changes in behaviors and lifestyle as it is to improved medical care
Physiological Conditions -- Problems in Glucose Metabolism
- Diabetes, a condition in which glucose can't be taken into the cells bc of probs in producing or using insulin; when this situation occurs, glucose remains in the blood at abnormally high levels - Ppl who have Type 1 are more likely to develop CVD, and longer-duration problems with glucose metabolism increase the risk - Type 2 also elevates the risk for CVD - Many ppl have probs w/ glucose metabolism that don't qualify as diabetes but may still create CVD risk - Such problems constitute one of the factors in the metabolic syndrome, a collection of factors proposed to elevate the risk for CVD - Other components of metabolic syndrome include excess abdominal fat, elevated BP, and probs with the levels of two components of cholesterol - Ppl w/ metabolic syndrome are twice as likely to exp CV health probs than those w/o syndrome - Problems in insulin metabolism more strongly predicted arterial damage than the other components
Behavioral Factors -- Weight and Diet
- Eval of obesity as an independent risk for CVD is difficult; main prob is that obesity is related to other risks, such as BP, Type 2 diabetes, total cholesterol, LDL, and triglycerides - High degree of abdominal fat is a risk factor for heart attack - Dietary choices ppl make may either increase or decrease their chances of developing CVD, depending on the foods they eat - Diets heavy in saturated fats are positively related to CVD and risk of heart attack - High-fat foods have obvious link to serum cholesterol lvls, but other nutrients may also affect CVD risks - Diets high in fruits and veggies predict lower CVD risks - A diet high in fish seems to offer some protection against heart disease/stroke; protective component is omega-3 fatty acids -- research on benefits yields mixed results as not all fish meals offer same protection - Diets high in antioxidants such as vit E, beta carotene or lycopene, selenium, and riboflavin show a number of health advantages; protect LDL from oxidation and thus from its potentially damaging effects on the CV system
Heart Disease Throughout the World
- Heart disease is the leading cause of death; total # of deaths from heart disease and stroke accounts for abt 30% of all deaths - In Finland, CVD rates fell more than 70% from the '70s through the '90s; part of this decrease was the result of a countrywide effort to change risk factors - That effort began with a community intervention that targeted an area of Finland w/ particularly high rates of CVD and attempted to change diet, hypertension, and smoking - This lowering of risk factors was largely responsible for the majority of the reduction - In contrast, heart disease has increased in countries that were once part of the Soviet Union; since '90, this epidemic has affected middle-aged men more than other groups, and the gender gap in heart disease is larger in Russia than in any other country - The risk of premature death from heart disease is 4x greater for a Russian man than for one in the US - In some countries in Eastern Europe, coronary heart disease accounts for 80% of deaths; avg life expectancy has decrease, and isn't expected to increase in the near future - Reasons for this plague of heart disease aren't completely understood, but lack of social support, and high levels of stress, smoking, and alcohol abuse are common, and these psychosocial and behavioral differences may underlie the increased rates of CVD - Heart disease/stroke are also leading causes of death in developing and underdeveloped countries, where an increase in heart disease and stroke continues - As tobacco smoking, obesity, physical activity, and dietary patterns in these countries become more like those of developed nations, CVD will increase in developing nations - Thus, worldwide burden of CVD is immense
Before Diagnosis: Preventing First Heart Attacks
- Ideally, ppl should prevent CVD by modifying risk factors before the disease process causes damage - A longitudinal study indicated that prevention is possible by maintaining a low level of risk factors to protect against CVD - Study examined young adult and middle-aged men and women in five large cohorts to see if a low-risk profile would reduce both CVD and other causes of mortality - After dividing participants into risk groups and screening for as long as 57 years, results indicated that low-risk participants had lower rates of death not only from CHD and stroke but also from all causes - Thus, young and middle-aged men and women who can modify CVD risks to attain low-risk profiles will also lower their risk for all-cause mortality and can expect to live 6-10 years longer - Factors included smoking, cholesterol levels, and BP -- 3 major risk factors for CVD - Importance of maintaining a healthy lifestyle may begin as early as childhood, when dietary and physical activity patterns are often established, and definitely continues during adolescence, when most smokers begin their habit - After ppl acquire high risks from behavioral factors such as smoking and unwise eating, managing those risks is more difficult - Most serious behavioral risk factor is cigarette smoking - Although hypertension and serum cholesterol are not behaviors, both can change indirectly through changes in behavior, making these factors candidates for intervention - Before ppl cooperate w/ programs to change their beh, they must perceive that these behs place them in jeopardy, which may be a problem for ppl who have no symptoms of CVD; these individuals may recognize established risk factors in calculating their personal risk, but they often display an optimistic bias in assessing their risk - Tend to believe that they are immune from the risks that make other ppl vulnerable - These thots place such individuals in the precontemplation or contemplation stage, according to the transtheoretical model, when they are not ready to make changes - Technique of motivational interviewing challenges ppl's beliefs with the goal of moving ppl toward making positive change; part of a successful program to increase fruit and vegetable consumption - Thus, moving ppl to the point of making changes in their health habits is a major challenge for health psychologists involved in CV health
Before Diagnosis -- Lowering Serum Cholesterol
- Interventions aimed at lowering cholesterol levels can include drugs, dietary changes, increased physical activity, or a combo of these components - Eating a diet low in saturated fat and high in fruits/veggies and maintaining a program of regular phys activity are good strategies for preventing high cholesterol levels - Dietary and exercise interventions are key components in managing high cholesterol levels - H/e, once a person develops high cholesterol levels, a prudent diet and phys activity aren't likely to lower cholesterol to an acceptable level; thus, many ppl w/ high cholesterol can't achieve substantially lower cholesterol levels through diet and exercise alone - Physicians may prescribe cholesterol-lowering drugs such as the 'statin' drugs to patients with high total cholesterol levels or high LDL levels - These drugs act by blocking an enzyme that the liver needs to manufacture cholesterol; esp effective in lowering LDL cholesterol and can reduce risks and improve survival of ppl at risk for CVD - Despite their effectiveness, these drugs require a prescription, cost money, and have side effects - Recommendations for cholesterol lowering are complex: 1. Relying on drugs to lower cholesterol w/o beh changes isn't a good strategy 1.a. Beh interventions can help both men and women adhere to a regular exercise program as well as a low-fat diet 1.b. Such adherence can lower LDL and improve the ratio of total cholesterol to HDL 1.c. If lifestyle changes don't lower cholesterol, then drugs are an option, but not before, esp for ppl with low levels of risk 2. Ratio of total cholesterol to HDL is more important than total cholesterol 2.a. Statins tend to lower LDL rather than raise HDL, but these drugs lower cholesterol and incidence of heart attacks/stroke, making them a good choice for ppl w/ very high or resistant cholesterol levels 3. Ppl w/ multiple risks for CVD, such as hypertension, diabetes, or smoking, should consider the task of lowering cholesterol as more urgent than those w/ fewer risks
Angina Pectoris
- Less serious result of restriction of the blood supply to myocardium - A disorder with symptoms of crushing pain in the chest and difficulty breathing - Usually precipitated by exercise/stress - With oxygen restriction, the reserve capacity of the CV system is reduced, and heart disease becomes evident - Sign of obstruction in the coronary arteries
How does lifestyle relate to CV health?
- Lifestyle factors such as cigarette smoking, unwise eating, and a sedentary lifestyle all predict CV health - During past 3 decades, deaths from heart disease have steadily decreased in the US; perhaps as much as 50% of that drop is a result of changes in beh and lifestyle - During this same time period, millions of ppl have quit smoking, altered their diet to control weight and cholesterol, and begun an exercise program
Psychosocial Factors -- Educational Level and Income
- Low socioeconomic status, often assessed by low educational level and low income, are risk factors for CVD - In particular, low edu placed ppl at increased risk for heart attack - In many countries, edu levels are related to ethnicity, but studies in the US, Netherlands, and Israel examined edu level w/i ethnic groups; results showed that, independent of ethnicity, low edu level increased risk for CVD - Factors linking low levels of edu to high levels of heart disease: 1. Ppl w/ low edu practice fewer health behaviors than those w/ higher educational levels 1.a. Eat a less healthy diet, smoke, and lead more sedentary lives - Income lvl another risk factor for CVD; ppl w/ lower incomes have higher rates of heart disease than ppl in the higher income brackets - Socioeconomic level, defined as education/occupation/income/marital status, related to CV risk factors as BP, body mass index, and cigarette smoking - Income level relates to longevity in the form of a gradient, w/ higher income predicting longer life - Social rank/status have a variety of CV effects in many species, including humans - Research suggests that these socioeconomic CV risks begin to accumulate during adolescence/childhood
Before Diagnosis -- Reducing Hypertension
- Lowering high BP into normal range is difficult b/c a number of physiological mechanisms act to keep BP at a set point - Many different feedback systems either raise or lower BP when the body senses that BP is out of the critical range - Body may even perpetuate hypertension by means of these feedback mechanisms, regulating BP to the hypertensive lvl instead of regulating it into normal range - B/c complex feedback systems work against rather than for the maintenance of appropriate BP, hypertension tends to be difficult to control - Interventions aimed at hypertension usually try to control BP through antihypertensive drugs that require a physician's prescription - Goal is typically to lower BP to 130/80 mmHg or lower - B/c hypertension presents no unpleasant symptoms and the medications may cause side effects, many patients are reluctant to follow this regimen - Several behs relate to both the development and the treatment of hypertension, and these behs are also targets of interventions - Obesity correlates w/ hypertension, and many obese ppl who lose weight lower their BP into the normal range - Thus, losing weight is part of BP control - Hypertensive individuals also typically receive recommendations to restrict sodium intake and make dietary changes - The Dietary Approach to Stop Hypertension (DASH) originated as a plan to control hypertension; includes a diet high in fruits, veggies, whole grains, and low-fat dairy products as well as other lifestyle changes (Table 9.3) - A regular physical activity program is also effective in controlling hypertension, esp in ppl who have been sedentary - Other techniques for reducing BP include stress management, meditation, and relaxation training - A program to control hypertension may have both drug and beh components
Chocolate May Help Prevent Heart Disease
- May contain chemicals that help prevent CAD - One of the dietary components that seems to offer some protection against artery damage is a class of chemicals called flavonoids, which are derived primary from fruits and veggies - Several subcategories of flavonoids exist, each with slightly different properties - The subcategory that contains chocolate is the flavonols, which also occur in tea, red wine, grapes, and blackberries - All subcategories have been linked to health benefits, including growing evidence of the advantages of chocolate - Not all chocolate contains the same amount of flavonoids, thus some types of chocolate may offer more protection than others - Processing of the cacao bean affects the flavonoid content - Dark chocolate contains 2-3x more flavonoids than milk chocolate or Dutch chocolate - Flavonoids exert their health benefits by reducing oxidation, making them one type of antioxidant; benefits may occur through effects on the lining of arteries - Flavonoids may be esp effective in protecting arteries against harmful effects of low-density cholesterol and increase vascular dilation - Chocolate consumption has also shown CV benefits in lowering BP and decreasing inflammation, both of which lower risk factors for CVD - High concentrations of this micronutrient also occur in green and black tea, grapes, red wine, cherries, apples, blackberries, and raspberries
Myocardial Infarction
- Medical term for the condition commonly referred to as a heart attack - Damage may be so extensive as to completely disrupt the heartbeat - Less severe cases, heart contractions may become less effective - Signals include a feeling of weakness/dizziness combined with nausea, cold sweating, difficulty breathing, and a sensation of crushing/squeezing pain in the chest, arms, shoulders, jaw, or back - Rapid loss of consciousness or death may occur, but the victim sometimes remains quite alert throughout the experience - Severity of symptoms depends on the extent of damage to the heart muscle - Damaged portion of the myocardium will not regrow/repair itself; scar tissue forms at the infarcted area - Scar tissue doesn't have the elasticity and function of healthy tissue, so a heart attack lessens the capacity of the heart to pump blood efficiently - Myocardial infarction can limit the type and vigor of activities that a person can safely do, prompting some lifestyle changes - Process of cardiac rehabilitation may involve psychologists to help patients adjust their lifestyle to minimize risk factors/lessen chances of future attacks; major task for the health care system
Psychosocial Factors -- Anger and Cardiovascular Reactivity
- One way that the expression of anger might relate to coronary heart disease is through cardiovascular reactivity (CVR), typically defined as increases in BP and heart rate due to frustration, harassment, or any lab stress task - Most past research on CVR used lab methods in which researchers presented participants w/ various situations intended to arouse anger and monitored their physiological responses, often using a variety of cardiac measurements such as BP and heart rate; sometimes measures also included the persistence of such cardiac responses - In one study using such a procedure, African American men showed a stronger BP response than did Euro American men or women from either ethnic group; result suggests that the higher prevalence of hypertension among African American men may relate to their tendency to higher reactivity - Another reactivity study focused on edu level and anger-coping strategies among African American men and found that low edu level and a high-effort style of coping are associated with higher BP reactivity - For African Americans, the exp's of racism constitute a source of anger, and one study connected the perception of racism w/ BP reactivity - This type of reactivity difference also appeared in a study comparing African American and Euro American women - Thus, reactivity may relate to hypertension among African Americans
The Dietary Approach to Stop Hypertension
- Originated as a plan to control hypertension; includes a diet high in fruits, veggies, whole grains, and low-fat dairy products as well as other lifestyle changes (Table 9.3) - DASH not only effective in lowering BP, but it also decreases the risk for stroke and CHD in women
Physiological Conditions -- Hypertension
- Other than advancing age, hypertension is the single most important risk factor for cardiovascular disease - Produces no overt symptoms, and dangerously elevated blood pressure levels commonly occur with no signals or symptoms - Framingham Heart Study provided the first solid evidence of the risks of hypertension - The higher the BP, the greater the chance of heart attack, heart failure, stroke, and kidney disease
Psychosocial Factors -- Social Support and Marriage
- Prospective studies confirm that lacking social support is also a risk for CVD - Loneliness during childhood, adolescence, and young adulthood relates to CVD risk factors, and these effects may become more serious w/ aging - Older ppl who had exp'd a heart attack were more likely to have another, fatal heart attack if they lived alone - Lack of social support may be a factor even more important in the progression of CVD - Studies that measured the progression of blockage of the coronary arteries in women found that support at home and work affected the progression of coronary artery blockage; high stress in either area predicted progressive blockage, whereas satisfactory support in both led to regression of arterial plaques - Another study showed that the number of ppl in a person's social network related to coronary mortality - Older men who were more socially involved were less likely to die of CVD than those were more isolated - Marriage should provide social support, and in general, married ppl are at a decreased risk for CV health problems - Quality of marital relationship may be a factor; marital quality was important - Marriage not beneficial if the individual was dissatisfied w/ their relationship - Happily married ppl received greater benefits in the form of lower BP than single ppl, even those w/ a supportive social network - Spouses/other sources of social support may reduce the risk of CV mortality by providing encouragement for compliance w/ a healthy lifestyle/medical regimen/by urging a person to seek medical care - Sources of social support are usually friends, family, spouses, ad even pets - Support may also affect CVD through its influence of the exp of stress and depression
Reducing Cardiovascular Risks
- Psychology's main contribution to CV health involves changing unhealthy behaviors before these behaviors lead to heart disease - Psychologists may help ppl who have been diagnosed w/ heart disease; often help cardiac rehabilitation patients adhere to an exercise program, a medical regimen, a healthy diet, and smoking cessation
Coronary Heart Disease (CHD)
- Refers to any damage to the myocardium as a result of insufficient blood supply - One can have CAD without CHD; just don't breakin' that heart, man - Myocardium can't survive without oxygen, just like Jordin Sparks - Coronary blockage results in the death of myocardial tissue, and infarction
Psychosocial Factors -- Stress, Anxiety, and Depression
- Relate to CVD, but also relate to each other - Overlap makes independent assessment of each component difficult; h/e, a great deal of evidence implicates these factors in CVD - Ppl who had heart attacks also exp'd more work/financial stress and more life events than their matched controls - In a large, prospective study of young adults in the US, increases in work-related stress led to greater incidence of hypertension 8 years later - Anxiety and depression also increase risk for CVD; evidence for the risks from depression is especially strong - Even after controlling for other risk factors such as smoking and cholesterol, anxiety/depression predict the development of CVD - Risks of depression/anxiety apply not only to the development of CVD, but also to its progression, as depression in the year following a heart attack predicts subsequent risk of CV mortality - Evidence for the beginnings of artery damage appeared in a study of depressed adolescents, which is consistent w/ the long-term damage that accompanies CVD - More evidence about the harm of negative emotions has come from the study of hostility/anger
Risk Factors in CVD
- Research links several risk factors to the development of CVD - Risk factor approach to predicting heart disease began with the Framingham Heart Study in 1948 1. Study was a prospective design; all participants were free of heart disease at the beginning of the study 2. Original plan was to follow these ppl for 20yrs to study heart disease and the factors related to its development 3. Results proved so valuable that the study has continued now for more than 50yrs and includes both children and grandchildren of the original participants 4. At the time of their discovery, medicine hadn't considered many typical American lifestyle behaviors to be particularly dangerous - Several large-scale studies followed, including the Nurses' Health Study 1. Long-term epidemiological study of women's health that confirms th elink between several risk factors and women's risk for CVD 2. The largest study of CV heath to date is the 52-country INTERHEART Study, which matched over 15,000 ppl who experienced a heart attack w/ nearly 15,000 similar ppl who hadn't 2.a. This case-control study examined a host of other potential risk factors, and the extent to which risk factors for CVD are similar across countries - Much of our knowledge about the risk factors for major CV problems comes from these studies - CV risk factors include those that are inherent, those that arise from physiological conditions, those arising from behavior, and a variety of psychosocial factors
Before Diagnosis -- Modifying Psychosocial Risk Factors
- Research the links psychosocial factors such as stress, anxiety, depression, and anger w/ CVD - Evidence for these risks is sufficiently compelling for some authorities to call for the development of 'behavioral cardiology', urging cardiologists to screen for psych risks and to recommend psych interventions to decrease anxiety/depression and to manage stress/anger - Consistent w/ this concept, research on ppl who received angioplasty indicated that those who had a more positive outlook about themselves and their future were less likely to exp a recurrence of CVD - Anger/negative emotions also a target of intervention, and clinical health psychologists recommend a variety of strategies for coping w/ hostility, anger, and depression - To reduce toxic element in anger, perpetually angry ppl can learn to become aware of cues from others that typically provoke angry responses; can also remove themselves from provocative situations before they become angry, or they can do something else - In interpersonal encounters, angry ppl can use self-talk as a reminder that the situation will not last forever - Humor is another potentially effective means of coping w/ anger, but it may present its own risks; sarcastic/hostile humor can incite additional anger, but silliness or mock exaggerations often defuse potentially volatile situations - Relaxation techniques can also be effective strategies for dealing w/ anger; includes progressive relaxation, deep-breathing exercises, tension reduction training, relaxing to the slow repetition of the word 'relax', and relaxation imagery, in which the person imagines a peaceful scene - Angry ppl can lower their BP by constructively discussing their feelings w/ other ppl - Discussing feelings w/ a therapist may also benefit ppl who are depressed, but physicians may not always recognize this problem; screening for depression among ppl at risk for CVD is an urgent need - Depression is also common among ppl who exp a heart attack or other CVD event - These individuals may be more willing to undertake changes to avoid another heart attack/stroke
Psychosocial Factors -- Suppressed Anger
- Results from early studies and more recent findings suggest that suppressing anger may be more toxic than forcefully expressing anger - One version of suppressed anger is rumination -- repeated negative thoughts about an incident -- which tends to increase negative feelings and depression - Ppl who suppress their anger but 'stew' over their feelings may be using a coping style that puts them in danger - H/e, expressing anger (and other negative emotions) in a forceful way may act as triggers for those with CVD, precipitating a heart attack/stroke - Aron Siegman suggested that ppl learn to recognize their anger but to express it calmly and rationally, in a way that will be likely to resolve rather than escalate a conflict - The manner in which a person expresses anger may affect CV health; ppl who discuss anger in a way that seeks to resolve a situation have better cardiovascular health, particularly among men - In contrast, ppl who justify their anger by blaming other ppl have greater long-term incidence of CV health problems - Thus, it may not be just the anger that increases risk for CV problems, but also the additional stress caused by alienating others w/ hostile expressions of anger - Anger combines w/ the negative emotions that accompany anxiety and depression to present greater risk for the development of CVD - Cynical hostility and anger relate to each other and may interact w/ other risk factors such as high BP to increase a person's risk for heart disease - Fig 9.9 -- Shows evolution of Type A beh pattern to hostility, to anger, to the expression/suppression of anger, and finally to negative emotionality
Summary thus far
- Since mid-'60s, deaths from CAD and stroke have steadily declined in the US and most other high-income nations - Although some of that decline is a result of better and faster coronary care, lifestyle changes account for 50% or more of this decrease - In low-income countries, the opposite has occurred; smoking and obesity have increased, and physical activity has decreased - These habits have increased risks for CVD, which will grow in these countries in the coming years
Psychosocial Factors -- Hostility and Anger
- Some types of hostility and anger are risk factors for CVD - Much of this research grew out of work on the Type A behavior pattern, originally proposed by cardiologists Meyer Friedman and Ray Rosenman - The two cardiologists described ppl w/ Type A behavior pattern as hostile, competitive, concerned w/ numbers and the acquisition of objects, and possessed of an exaggerated sense of time urgency - During early years of its history, Type A beh pattern demonstrated promise as a predictor of heart disease, but later researchers were unable to affirm a consistent link b/w the global Type A beh pattern and incidence of heart disease - Situation led investigators to consider the possibility that some component of the pattern, rather than the entire pattern, might be a predictor - Hostility appeared to be the component of Type A that was risky; in 1989, Redford Williams suggested that cynical hostility is esp harmful to CV health - Contended that ppl who mistrust others, think the worst of humanity, and interact w/ others w/ cynical hostility are harming themselves and their hearts - Suggested ppl who use anger as a response to interpersonal problems have an elevated risk for heart disease - Hostility early in life does predict CV health later in life - One long-term prospective study w/ young adults who scored high in hostility had higher levels of coronary calcification (a precursor of atherosclerosis) at a 10-year follow-up than young adults low in hostility - Higher levels of hostility also predicted greater incidence of hypertension at a 15-year follow-up - In addition to increasing risk for these two precursors to CVD, a recent review of over 20 longitudinal studies confirmed hostility as a significant predictor of subsequent CVD - CV health of men, in particular, relates to both hostility as well as anger - Anger and hostility may seem the same, but they have important differences: 1. Anger is an unpleasant emotion accompanies by physiological arousal 2. Hostility is a negative attitude toward others - The exp of anger is probably unavoidable and may not present much of a risk; h/e, the manner in which a person deals w/ anger may be a factor in the development of CVD - Some evidence suggests that either expressing anger or suppressing anger may pose some problems
The Coronary Arteries
- Supply blood to the heart muscle, the myocardium - Fig 9.2; two principal coronary arteries branch off from the aorta, the main artery that carries oxygenated blood from the heart - Left and right coronary arteries divide into smaller branches, providing the blood supply to the myocardium - w/ each beat, the heart makes a slight twisting motion, which moves the coronary arteries, receiving a great deal of strain as part of normal function - This movement is hypothesized to almost inevitably cause injury to the coronary arteries - Damage can heal in two different ways: 1. Preferable route involves the formation of small amounts of scar tissue and results in no serious problem 2. Involves formation of atheromatous plaques, deposits composed of cholesterol and other lipids, connective tissue, and muscle tissue - Plaques grow and calcify into a hard, bony substance that thickens the arterial walls; also involves inflammation - Formation of plaques and the resulting occlusion of the arteries are called atherosclerosis (Fig 9.3) - Related but different problem is arteriosclerosis or the loss of elasticity of the arteries; beating of the heart pushes blood through the arteries with great force, and elasticity allows adaptation to this pressure - Loss of elasticity tends to make the CV system less capable of tolerating increases in cardiac blood volume; potential danger exists during strenuous exercise for people with arteriosclerosis - Formation of arterial plaques (atherosclerosis) and the "hardening" of the arteries (arteriosclerosis) often occur together - Both can affect any artery in the CV system, but when the coronary arteries are affected, the heart's oxygen supply may be threatened
What are the structures, functions, and disorders of the CV system?
- System includes the heart and blood vessels (veins, venules, arteries, arterioles, and capillaries) - Heart pumps blood t/o body, delivering oxygen and removing wastes from body cells - Disorders include: 1. Coronary heart disease; occurs when arteries that supply blood to the heart become clogged w/ plaque and restrict blood supply to heart muscle 2. Myocardial infarction (heart attack); caused by blockage of coronary arteries 3. Angina pectoris; a nonfatal disorder w/ symptoms of chest pain and difficulty in breathing 4. Stroke; occurs when oxygen supply to the brain is disrupted 5. Hypertension (high BP); a silent disorder but a good predictor of both heart attack and stroke - Heart attack and stroke account for more than 30% of deaths in the US
Stroke
-Atherosclerosis and arteriosclerosis can also affect the arteries that serve the head and neck, thereby restricting blood supply to the brain - Any obstruction in the arteries of the brain will restrict/completely stop the flow of blood to the area of the brain served by that portion of the system - Oxygen deprivation causes death of brain tissue within 3-5 minutes, resulting in a stroke - Strokes can have other causes, like an air embolism or an infection that impedes blood flow in the brain - Weakening of artery walls associated w/ arteriosclerosis may lead to an aneurysm, a sac formed by the ballooning of a weakened artery wall; may burst, causing a hemorrhagic stroke or death (Fig 9.5) - A stroke damages neurons, and these neurons have no capacity to replace themselves - Some neurons devoted to a particular function are lost, impairing brain function; extent of loss is related to the amount of damage to the area - Damage may be so extensive, or in such a critical area, as to bring about immediate death, or damage may be so slight as to go unnoticed