Bone Abstracts

Objectives: To determine the prevalence and intensity of D-deficiency in children and adolescents in the metropolitan area with subtotal deficiency of ultraviolet B (55° N).

Methods: From May 2008 to May 2010 in a random sample of 163 Muscovites 0–18 years old (9.9±0.4; girls/boys, 81/82) serum 25-hydroxyvitamin D content was determined by chemiluminescent analysis (DiaSorin, Inc., USA; n=56 and Roche Diagnostics; n=107). The results were evaluated according to the criteria McKenna & Freaney (1998).

Results: The 2-year overall frequency of subnormal vitamin values (<40 ng/ml) was 77%. Mild decrease (20–<40) is set at 32% of young Muscovites, moderate (10–<20) – 30%, severe (<10) – 15%. A mild deficiency prevailed from May to August (43±7%, n=54 vs 27±4%, n=109 in the remaining months, RR=1.6 with 95% CI (1.03–2.5); P<0.04), and more severe (<20 ng/ml) – from September to April (53±5%, n=109 vs 28±6%, n=54 for others, RR=1.9 (1.2–3.1); P=0.002). Gender differences were not found. Between chronological age and separate degrees of D-deficiency was found the weak correlation (r=+0.23–0.32; P=0.0008–0.004). The sole category of children with the best vitamin status were at the age of 0–3 years: they had normal levels three times more common (‘>40 ng/ml’: 57±11%, n=23 vs 18±3%, n=140 in patients 4–18 years, RR=3.2 (1.9–5.2), P=0.0001) and three times more rare were cases with moderate to severe D-deficiency (‘<20’ 17±8% vs 49±4%, RR=0.35 (0.14–0.87), P<0.009).

Conclusion: In Russian largest metropolis with geographical and social disadvantage (due to low insolation and absence of mass prophylaxis) most children older than 3 years and adolescents have vitamin D insufficiency; this unfavorable feature revealed regardless of sex, often manifests with moderate to severe degree, for the most part of calendar year.