5 Vitamin D- natural sources >90% of humankind’s vitamin D comes from UV-B exposure of skin20-30 min of direct skin exposure to midday sun on face and arms, 2 or 3 times weekly provides sufficient for a fair-skinned personAbove 43oN, the angle of sun to atmosphere filters out useful UV wavelengths between October and April.
6 Vitamin D- natural sources Sun block lotion SPF-8 prevents 95% of dermal vitamin D synthesisWearing a hat, veil or head scarf very substantially reduce skin vitamin D synthesisPigmented skin or elderly (thin skin) needs more exposure for same vit D productionImpossible to overdose on skin synthesised vitamin D; possible to sunburn
7 Scale of the public health problem Seasonal & geographic variation in prevalence of 25-OHD <40nmol/LMRC 1958 birth cohort at age 45yrs =7437 whitesSpring nadir for 25OHD <20 nmol/L =16%<50 nmol/L =50%Hyppönen & Power 2007
8 Vitamin D- natural sources FoodOily fish (top of the marine ecosystem)Salmon, trout, mackerel, herring, fresh tuna, sardines, pilchards, anchoviesFish oils (cod liver oil)2 portions of oily fish weekly ( g) sufficient to provide sufficient Vit DLess Vitamin D in farmed fishHeavy metals in some sea fish
9 Vitamin D- natural sources Common misconceptionsNegligible amount of vit D in milkNone in green vegetablesSmall amounts in Egg yolk (20 yolks per day sufficient)Small amount in mushrooms (100 per day sufficient)Small amounts in animal liver (inc. seal liver)Statutory supplementation in UKInfant milk formula (500 IU/l)Margarines ( IU/100g)
10 How to determine vitamin D status? Measure serum 25 hydroxyvitamin D (25-OHD)Robust marker of vit D storesHalf-life 3-4 weeksDon’t measure 1,25 dihydroxyvitamin DActive ‘D hormone’Circulating levels reflect PTH action and calcium supplyOften falsely normal or even elevated in D deficiency
11 How to determine vitamin D status? 25-OHD(nmol/l)Vit D statusManifestationAction<25DeficientRicketsOsteomalaciaTreat withhigh dose D25-50InsufficientAssociated with disease riskSupplement with vit D50-75AdequateHealthyLifestyle advice>75OptimalNone
12 Interpretation of serum 25-OHD Men (n=3725)Women (n=3712)• UK-wide white cohort born 1958Hypponen & Power 2007
13 Interpretation of serum 25-OHD Men (n=3725)Women (n=3712)• UK-wide white cohort born 1958Hypponen & Power 2007
15 35 yo, Pakistani-born Lady Living in Fenham for 11 yrsMigratory aches and pains, hips, legs, back during 3rd pregnancyGP re-assured, but ? Depressed4/12 post partum-feels low, aches and pains persist= Fluoxetine 20mg odPresents limping, with pain in R hip
16 GP did blood tests Calcium =1.89 mmol/l (2.12-2.6) Alk Phos = 231 KIU/l (<120)Rh factor negativeRefer endocrinology
19 Treatment Oral ergocalciferol 10,000 IU daily for 3 months Feels a lot better, aches and pains gone, smiling in clinicBut……..
20 After topping up her vitamin D levels, she will need long-term maintenance 1000 to 2000 IU calciferol dailyRegular sunlight exposureDon’t forget the baby: who was slow to walk and had rickets with tibial deformities
23 20 month old girl Mother reports lower limb deformity 4th child, term birth, no problemsBreast fed until 8 monthsPain on walking, difficulty climbing stairsNigerian mother, asylum seeker housed in tower block3 older brothers born in Nigeria, no problems
24 Treatment Ca 1.92 mmol/l (2.3-2.7) PO4 1.26 mmol/l (1.1-1.85) Alk Phos 1077 KIU/l (<375)TreatmentErgocalciferol oily solution, 3,000 IU/ml. 2mls dailyMother and brothers, also to take supplements: Dalivit 0.6 mls daily
25 Healthy Start/ Sure Start The UK health departments recommend a daily dose of vitamins A, C and D for:breastfed infants from 6 months (or from 1 month if there is any doubt about the mother's vitamin status during pregnancy)formula-fed infants who are over 6 months and taking less than 500 ml infant formula per daychildren under 5 years of ageThis recommendation is particularly important for children who are picky or fussy eaters, those of Asian, African, Afro-Caribbean or middle eastern origin and those living in northern areas of the UK.
28 45 yo woman Multiple sclerosis diagnosed age 29 Only 2 major attacks Feeling increasingly weak for 30 monthsPainful to move legs, can’t stand upUsing wheelchair, even in houseNeeds husband to pull her out of bed in morning
29 Fell out of bed one day Wedge # of L2 vertebral body BMD measured; T score -3.4 at spineBone chemistry(PTH 43)Treated with calcichew D3 one dailySerumFebAprilCalcium2.602.30PO41.110.77Alk Pase624825-OHD1011
30 Allergic to fish; none since teenager Not really leaving the house due to mobilityNo overseas holiday for 5 yrs
31 TreatmentOral colecalciferol 20,000 IU capsules, 3 per week (Dekristol; pharmacy special order, approved by APC)Vomiting and diarrhoea (contains fish oil!)IM ergocalciferol 300,000 IU monthly for 3 months,Oral vitamin D3 2 x 25ug capsules daily (2000 IU) from Holland and Barrett1 year later; walks unaided up to 200 m, no pain
32 How to determine vitamin D status? 25-OHD(nmol/l)Vit D statusManifestationAction<25DeficientRicketsOsteomalaciaTreat withhigh dose D25-50InsufficientAssociated with disease riskSupplement with vit D50-75AdequateHealthyLifestyle advice>75OptimalNone
34 Also OTC Boots (12.5 ug capsules) £2.99 for 90 Holland & Barrett (25 ug capsules) £6.99 for 100
35 Dosing issues100 IU calciferol daily increases serum 25-OHD by 2.5 nmol/lRDA is 400 IU (10 ug)Increase serum 25-OHD by 10 nmol/lTypical Newcastle patient with vitamin D insufficiency has levels between 20 and 30 nmol/lNeed to aim for 70 nmol/l or betterToxicity seen at levels of 500 nmol/l or higherIU daily is appropriate maintenance dose (Adults)
36 Tips on treatmentMost people who you suspect are D deficient, are D deficientSupplementation is not the same as treatmentIf a child has rickets, the siblings and mother should also be treatedCompliance with calcium containing preparations (calcichew D3) is poor, better to prescribe D only compounds for longterm use
38 Questions• Is it worth screening all new patients from overseas at risk of vit D?-When people first arrive, they aren’t deficient-Probably takes 5 years or a pregnancy to manifest severe D deficiency-Worth giving dietary/sunlight exposure advice to all at risk groups
39 Questions Treatment- injection vs oral medication and how long for? -Oral is better (all round); but current supply issues.-In severe deficiency a short course of monthly IM insures treatment is received-If GI problem, IM worthwhile
40 Questions How often to monitor bloods once on treatment? -Depends on manifestations, but maybe never or once in a year until dietary intake is no longer an issue-If Alk. Phos raised, recheck in 3 and 6 months; although it may take longer to normalise
41 Questions When to refer?- and who to endocrine vs bone clinic Doubt about diagnosis; conflicting biochem (eg. Hypercalcaemia)Failure to respond to treatmentOther nutritional issues (IDA frequently co-exists)Childhood with bone disease- Vitamin D is actually a hormone
42 QuestionsPatients with aches and pains and confirmed vit D def- should we be x-raying jointsI generally don’t, unless there is very localised pain (not generalised aches & pains)Pain not improved by 3 months treatment should trigger an X-ray
43 Dosing of colecalciferol in Autumn Placebo10,000 U/d5,000 U/d1,000 U/dFrom Heaney RP et al.