Vitamn D

Question 1

Vitamin D Facts

Answer 1

Fat-soluble prohormone
Role in calcium regulation and bone development
Obtained through exposure to sun
Derived from food or supplements
Must be converted in body to an active form
Review your patho for Vit D metabolism

Question 2

Vit D research

Answer 2

Associated with bone health
decreased vit D assoc w/Increased risk for Cancer
Low vit D levels assoc w/Increased risk for MI in men
Epidemiology studies: increase prevalence of cancer, DM, CVD, MS, cognitive impairment in persons with lower serum 25-OH-D levels.

Question 3

Vit D Deficiency Presenting Symptoms

Answer 3

Bone pain
Muscle aching
Proximal muscle weakness- falls
Impaired LE function, higher fall rates, muscle weakness
AGS Consensus Statement 2014
Nonspecific Low back pain

Question 4

Risk Factors/Groups at Risk

Answer 4

Older adults - need 3-4x more sun exposure d/t decreased ability to absorb and process
Breast fed infants
Obese individuals - store vit D in fat so more is stored than is available to synthesize
Pigmented skin - need 5x more sun exposure to synthesize enough vit D than fair skinned people
Malnutrition/malabsorption - pancreatic insufficiency, cholestatic liver dz, GB, IBD, gastrectomy
Drugs:
anticonvulsants, rifampicin, antiretroviral drugs – affect metabolism of vit D
Cholestyramine- decreases absorption
Orlistat – decreased absorption affects fat malabsorption and causes decreased vit D levels

Question 5

Results of Vit D Deficiency

Answer 5

In children: Rickets - Defective mineralization of growing skeleton - softened bones, deformities, esp. leg deformities (classic sign), growth retardation
In adults: osteomalacia - Defective skeletal mineralization - muscle aches, proximal weakness, increased risk for fx

Question 6

Cut Off Points in Practice

Answer 6

Sufficiency >30ng/mL
Insufficiency 20-30ng/mL
Deficiency <20ng/mL
(some debate on cutoff levels between organizations, but this is what we use for practice)

Question 7

Monitoring Levels

Answer 7

Screen by drawing Serum 25-OH-D
Routine screening not necessary ( according to IOM)
Screen persons at risk
No recommendations on frequency
Many insurers only cover for specific dx:
Chronic kidney disease Stage 3, 4, 5, osteoporosis, parathyroid disorders, hypercalcemia
Inform pts that insurance may not cover - cost ~$200

Question 8

Prevention and Tx - Diet and Sun Exposure

Answer 8

Diet: fish- tuna, mackerel, salmon, egg yolk, mushrooms and fish liver oil sardines or tuna canned in oil
Fortified cereals, milk, fruit juice and drinks
Sensible sun exposure
10-15 min. unprotected from 12-2 p.m. twice weekly
Can not overdose on Vitamin D from sun exposure
Excess is stored in fat – released during winter
Not recommended by American Academy of Dermatology

Question 9

Prevention and Tx - Supplementation

Answer 9

Ergocalciferol (vitamin D2) - vitamin D deficiency – 50,000IU weekly x 8- 12 weeks
comes from D2 irradiation of the yeast and plant sterol
Cholecalciferol (vitamin D3) – usually used for maintenance 800-2000IU vit D3 daily
obtained from oily fish and by skin synthesis.

Question 10

Recommendation for Children

Answer 10

400IU/day
Infants – prior weaning
Infants, children, adolescents – taking <1L vit D fortified formula/milk, no vitamin supplement

Question 11

Vit D Toxicity

Answer 11

Rare

Symptoms:nausea, vomiting, poor appetite, constipation, increased thirst, depression, increased urination, weight loss

Question 12

Recommendations for Fall Prevention

Answer 12

Vitamin D 1000IU/day plus calcium to community dwellers >65 and institutional settings
Review adults’ vit D intake for all sources (diet, supplements, sunlight) and discuss strategies to achieve total Vitamin D input
Recommend 4000IU daily from all sources = 30ng/ml
Routine lab testing not necessary before beginning supplementation
Not necessary to routinely monitor 25(OH)D level when supplementation is within recommended limits
If you chose to monitor test after 4months

Question 13

Patient Recommendations

Answer 13

Take 1000-2000 IU/day
Take at least 2 servings of dairy/soy/almond milk porducts/ day
Serving of tuna or mackerel often
Sitting out in sun 5-10min/day

Question 14

Practical Tips

Answer 14

Use daily dosing or weekly
Don’t take with cholestyramine, high-fiber cereals (bran and oatmeal), fiber stool softeners
Take with meals containing oils = enhanced absorption
Gel caps may contain oils – may cause allergic sx (diarrhea or rash)
Strict vegan – vit D2
Kosher vit D – D3 or D2 when derived from wool sheared from live sheep