Vitamin D Deficiency
USPSTF Recommendation
Inadequate evidence for primary prevention of fracture with Vitamin D & Calcium up to Calcium 1000 mg daily and Vitamin D 400 units daily
For which of the following patients would you NOT recommend Vitamin D screening? a) 41 yo male who had a Roux-en-y gastric bypass two months ago b) 25 yo female who is 12 weeks pregnant c) 85 yo male living in a skilled nursing facility with a history of falls d) 30 yo male with type 1 diabetes and a BMI of 22
d) 30 yo male with type 1 diabetes and a BMI of 22
Natural Vitamin D Production
1) Between 10 AM and 3 PM in Spring, Summer, and Fall 2) Approx 10,000 to 25,000 units is equivalent to exposure to 1 minimal erythemal dose (slight pinkness to skin 24 hours after exposure) in a bathing suit 3) Exposure of arms and legs to 0.5 minimal erythemal dose is equivalent to ingesting approx 3,000 units of vitamin D3 4) Above or below latitudes of 33 degrees, skin synthesis of Vitamin D is nonexistent in the winter
Institute of Medicine Recommendations
1) Calcium and Vitamin D play a key role in skeletal health 2) Goal 25-OH-D of over 20 ng/mL 3) Vitamin D 600 units ages 1 to 70 4) Vitamin D 800 units ages 71+ 5) Meets over 97.5% of population needs *NOTE: Institute of Medicine goal levels are lower than recommendations by the AACE/ACE Guidelines*
Vitamin D2 and Vitamin D3
1) D2 (ergocalciferol) and D3 (cholecalciferol) 2) D2 comes from a plant sterol and yeast D2 is the form in some prescription supplements of vitamin D 3) Vitamin D3 is synthesized from a cholesterol precursor D3 is available over the counter, and is the type made in our own bodies 4) Commonly available over the counter doses are: a) Vitamin D3 1000 units (tablet or capsule) b) Vitamin D3 2000 units (tablet or capsule) c) Vitamin D3 5000 units (typically capsule only) 5) Dose for dose, D2 and D3 will raise the serum level the same amount. D3 may be more effective over the long term because it has a long 1/2 life (lasts over 1.5 months), which allows it to be more stable
Learning Objectives
1) Identify risk factors for Vitamin D deficiency and patients who may benefit from screening 2) Describe the health risks associated with Vitamin D deficiency 3) Be able to recommend appropriate Vitamin D replacement and follow-up for patients with Vitamin D deficiency
Consequences of Vitamin D Deficiency
1) Increase parathyroid hormone levels a) Increases osteoclastic activity b) Increased risk of osteoporosis & osteopenia 2) Phosphaturia a) Mineralization defect in skeleton = rickets in children b) Osteomalacia in adults 3) Muscle weakness 4) Women with low Vitamin D at future risk for multiple sclerosis
Clinical Questions
1) Is the patient at risk for Vitamin D deficiency? 2) Is screening reasonable? 3) If deficiency is present, what is the best treatment option? What is the treatment goal? 4) Differences in winter vs summer dosing?
USPSTF Recommendations on Vitamin D Screening
1) Is there direct evidence that screening for Vitamin D deficiency results in improved health outcomes? Unknown 2) Are there differences in screening efficacy between patient subgroups? Unknown 3) What are the harms of screening (ex: risk for the procedure, false positives, and false negatives)? Unknown 4) Does treatment of Vitamin D deficiency using Vitamin D lead to improved health outcomes? Decreased risk of death in older institutionalized persons, lower rates of falls per person, not associated with decreased risk of fractures 5) What are the adverse effects of treatment of Vitamin D deficiency using Vitamin D? No association with increased adverse effects
Other Causes of Vitamin D Deficiency
1) Malabsorption Syndromes 2) Bariatric Surgery 3) Nephrotic Syndrome 4) Medications that may enhance the catabolism of 25(OH)D and 1,25(OH)2D, including anticonvulsants and antivirals used to treat HIV
Candidates for Vitamin D Screening
1) Rickets 2) Osteomalacia 3) Osteoporosis 4) Chronic kidney disease 5) Hepatic failure 6) Malabsorption syndromes 7) Cystic fibrosis 8) Obese children and adults (BMI 30 kg/m^2) 9) Inflammatory bowel disease 10) Crohn's disease 11) Bariatric surgery 12) Radiation enteritis 13) Hyperparathyroidism 14) Medications a) Antiseizure medications b) Glucocorticoids c) AIDS medications d) Antifungals, ex: ketoconazole e) Cholestyramine 15) African American & Hispanic children and adults 16) Pregnant and lactating women 17) Older adults with history of falls 18) Older adults with history of nontraumatic fractures 19) Granuloma-forming disorders 20) Sarcoidosis 21) Tuberculosis 22) Histoplasmosis 23) Coccidiomycosis 24) Berylliosis 25) Some lymphomas
A 62 yo female recently diagnosed with osteoporosis has a Vitamin D level of 22 ng/mL 1) Which of the following treatment options would you recommend? a) Ergocalciferol 6000 units daily b) Cholecalciferol 2000 units daily c) Cholecalciferol 50,000 units weekly d) Cholecalciferol 10,000 units daily 2) When would you want to check a follow-up Vitamin D level? a) 6 weeks b) 8 weeks c) 12 weeks d) 16 weeks
1) Which of the following treatment options would you recommend? c) Cholecalciferol 50,000 units weekly 2) When would you want to check a follow-up Vitamin D level? b) 8 weeks
Why are so many people deficient in Vitamin D?
Inadequate exposure to sunlight 1) Wearing sunscreen with SPF 30 reduces Vitamin D production by 95% 2) People with naturally dark skin require 3 to 5 times longer in sunlight to produce the same amount of Vitamin D