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
Background

Vitamin D3 (cholecalciferol) is obtained
from 2 sources:

Sunlight exposure (UV-B rays)

Dietary intake: oily fish products, fortified
products and supplements.
Formation of cholecalciferol
7-dehydrocholesterol
Background
Definitions
Davies et al, Arch Dis Child 2010; Cheetham et al, BMJ 2010; Misra et al Pediatrics 2008
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 2001-2004, 25-OHD measurement
61%, 37.5-72.5 nmol/l
9%, < 37.5 nmol/l
association with cardiovascular risk factors
what is the prevalence of vitamin D deficiency in UK children?
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
Recent trends & clinical features of vitamin D deficiency
presenting to a children’s hospital in Glasgow
Ahmed et al, Arch Dis Child, 2010
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
Stages of Tibia Vara
1
2
3
4
5
6
Changing incidence of slipped
capital femoral epiphysis:
A relationship with obesity
JBJS Br. 2008; 90: 92-4
31.1.10
2.6.10
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)
Vitamin D deficiency in children presenting to the
paediatric orthopaedic clinic, Southampton (2)
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.
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”
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
Healthy start uptake South East 2010
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’
Fractures
in 348 children
Hand
7.5%
Femur
4.9%
Tibia/fibula
7.8%
Ankle
9.8%
Radius/ulna
54.9%
Humerus
13.5%
Other
1.7%
Fat mass substantially inhibits
bone accrual in children with
prior fracture
JBMR 2009
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