1. Epidemiology of vitamin D deficiency in children presenting to a paediatric outpatient service in the UK J M Reed, J H Davies, L Blake, A Jackson, N M P Clarke Southampton General Hospital & University of Southampton

3. Background Vitamin D3 (cholecalciferol) is obtained from 2 sources:
Sunlight exposure (UV-B rays)
Dietary intake: oily fish products, fortified products and supplements.

4. Formation of cholecalciferol
7-dehydrocholesterol

5. Background

7. Definitions
Davies et al, Arch Dis Child 2010; Cheetham et al, BMJ 2010; Misra et al Pediatrics 2008

8. Prevalence of vitamin D deficiency in developed countries, adults vs
Prevalence of vitamin D deficiency in developed countries, adults vs. children
Hypponen et al, Am J Clin Nutr, 2007
n=7347, age 45 y, UK, all white, winter/ spring 25-OHD measurement
87.1% < 75 nmol/l
46.6% < 40 nmol/l
15.5% < 25 nmol/l
Ford et al, Ann Clin Biochem, 2006
n=830, UK adults, multicultural inner city, Sept 25-OHD measurement
< 25 nmol/l: 1 in 8 White
1 in 4 Black Afro-Caribbean
1 in 3 Asians
Kumar et al, Pediatrics, 2009
n=6275, USA, age 1-21 y, NHANES , 25-OHD measurement
61%, nmol/l
9%, < 37.5 nmol/l
association with cardiovascular risk factors
what is the prevalence of vitamin D deficiency in UK children?

9. Mode of presentation of symptomatic vitamin D deficiency in the UK
16 infants (6 Asian, 10 Black) from UK
all breast fed
6 cardiac arrest
3 died
8 ventilated
2 required by-pass
12 required IV support
2 referred for cardiac transplant
Heart 2006

10. Recent trends & clinical features of vitamin D deficiency presenting to a children’s hospital in Glasgow
Ahmed et al, Arch Dis Child, 2010

11. Methods
Prospective study to investigate the prevalence of deficiency in our patient population
Vitamin D level in known bone pathologies
- or
Requested as part of investigative work-up for unexplained bone pain

15. Stages of Tibia Vara

22. Changing incidence of slipped capital femoral epiphysis: A relationship with obesity
JBJS Br. 2008; 90: 92-4

26.
2.6.10

27. Vitamin D deficiency in children presenting to the paediatric orthopaedic clinic, Southampton (1)
25-OHD measured in those with bone pain or deformity
187 children from 2008 – 2010
75 deficient (60 insufficiency, 15 severe deficiency)

28. Vitamin D deficiency in children presenting to the paediatric orthopaedic clinic, Southampton (2)

29. Further analysis
No specific diagnosis was associated with a high or low vitamin D level
There was a lower vitamin D level found in children with unexplained joint pain (mean 22.5) compared to those with other diagnoses (mean 30.7). This was significant p<0.05.

32. Prevention Infant vitamin D RNIs
8.5 ug/d up to 6 months age
7 ug/d up to age 3 years
Chief Medical Officer, 20/1/2011, DOH website
“children from the age of six months to five years old should be given a daily 7 micrograms vitamin D supplement”

33. Prevention: Healthy Start
7.5 ug vitamin D3
Free for some from age 6 months
can be given from age 1 month on doctor’s advice
Also contain vitamin A and vitamin C
Can be bought £1.78/bottle

34. Healthy start uptake South East 2010

35. Significance Sunlight exposure
15 – 20 minutes uninterrupted sunlight 3 times per week
Vitamin D supplements
Vitamin D status sought prior to commencing ‘observation or orthopaedic surgical intervention’

37. Fractures in 348 children Femur Hand 4.9% 7.5% Tibia/fibula 7.8% Ankle
9.8%
Radius/ulna
54.9%
Other
1.7%
Humerus
13.5%

38. Fat mass substantially inhibits bone accrual in children with prior fracture
JBMR 2009

39. Summary Majority of active vitamin D from sunlight
Increase in cases of symptomatic vitamin D deficiency (not exclusive to poverty/ethnic minorities)
Need for raised awareness and improved public health measures