Endocrine Abstracts

Introduction: The importance of vitamin D beyond bone health is increasingly recognised. As a result Ireland has recently introduced a policy of vitamin D supplementation for all infants. A vitamin D level of 50 nmol/l for children/adolescents has been recommended as sufficient (1). We sought to establish the vitamin D status in children and adolescents attending a Paediatric Endocrinology Department and explore the relationship between vitamin D status and age, sex, body mass index (BMI) and seasonality.

Methods: A retrospective review of vitamin D levels was conducted (n=73). Vitamin D was measured using HPLC mass spectrometry. BMI and age at time of first vitamin D was recorded. BMI Z scores were calculated. Data analysed using Minitab.

Results: Seventy-three children (30 boys) were included in the analysis with mean age (S.D.) of 9.0 (5.0; range 1–16 years). Diagnoses included trisomy 21, diabetes, short stature and precocious puberty. Fifty percent of children were classified as overweight or obese. Only 36% had a vitamin D level >50 nmol/l with mean of 40.55 (19.97) nmol/l (range 10–84 nmol/l). There was no difference between boys and girls (P=0.581). There was an inverse correlation between vitamin D status and age (P=0.001) as vitamin D decreased with increasing age. There was no correlation between BMI and vitamin D level (P=0.292). A seasonal effect was evident, with the highest median vitamin D in September and the lowest in December.

Conclusions: This study demonstrates the importance of assessing vitamin D status in the older child and adolescent as only 36% had a level greater than the 50 nmol/l recommended. It is important to consider seasonal effects when assessing vitamin D status. Further study is required to investigate the vitamin D status of Irish children and adolescents to ascertain if the national guidelines for supplementation should be broadened.