Endocrine Abstracts

Background: Vitamin D (25(OH)D) deficiency is a global public health issue. An association with obesity and diabetes has been described in adult and paediatric populations. This study investigates the prevalence of 25(OH)D deficiency and its correlates in population of Emirati children and adolescents attending a large diabetes centre in the United Arab Emirates.

Methods: Participants aged 4-19 years were selected based on diabetes status [type 1 diabetes (T1D), normoglycaemic non-diabetic (NG)] from Abu Dhabi Diabetes and Obesity Study. Body composition was assessed using bioelectrical impedance analysis (Tanita^®). BMI percentile was categorized based on CDC recommendation. 25(OH)D cut-offs were defined as deficient (<30nmol/l), insufficient (30-50nmol/l) and sufficient (>50nmol/l) using WHO Criteria.

Results: In total, 148 participants with T1D and 296 age and sex-matched normoglycaemic controls were included. The prevalence of 25(OH)D (<30nmol/l) deficiency was 22.3% (n = 33) in T1D and 40.5% (n = 120) in control group. A decline in 25(OH)D levels was observed with increasing age in both groups, from 4-7 years to 15-19 years [T1D, P = 0 .018), NG, P = 0 .0001]. A larger proportion of females were 25(OH)D deficient in both groups (NG: 52.6% vs 23.6%, P < 0.0001; T1D: 31.7% vs 10.6%, P = 0 .0020). After adjusting for age and sex, children and adolescents with BMI≥95^th percentile were 2.5 times more likely to have 25(OH)D deficiency (OR: 2.69; 95% CI: 1.56, 4.64) than those with BMI 5^th-<85^th percentile. A negative correlation was observed between adiposity measures and 25(OH)D levels in both groups (T1D P < 0.01, NG, P < 0.001).

Conclusion: Vitamin D deficiency is common among Emirati children and adolescents. The lower prevalence among T1D population described here may represent better treatment compliance. Our study also confirms an association between vitamin D deficiency with obesity in general and with body fat mass in particular.