Lower 25(OH)D level in children born in winter-spring is a known phenomenon in countries with pronounced climate seasonality, it may strongly influence physical development and morbidity. We present retrospective analysis of pediatric (till 17 years) serum 25(OH)D tests performed in Children’s Clinical University Hospital Laboratory in 2012-2019 on Cobas e601 (Roche). 16042 tests were assessed, including 2645 infant samples, together with age, month of birth and testing year. Data was analyzed by IBM SPSS v25 (Kolmogorov-Smirnov test for differences). Significant differences of 25(OH)D in children born in winter/spring (WS) and summer/autumn (SA) were found, most prominent in the first year of life, but disappearing only by 2 years.
Median 25(OH)D level in infants (0-11 months) was 34.46 ng/mL in WS-born and 37.51 in SA-born (p=2E-5). In 2012-2015 it was, respectively, 28.85 and 38.61 ng/mL (p=1E-8) and in 2016-2019 - 36.81 and 37.59 ng/mL (p NS).
Median rate of 25(OH)D <20 ng/mL was 27.1% in WS-born infants and 18.7% in SA-born (p=1E-4). In 2012-2015 it was, respectively, 36.8% and 20.4% (p=6E-7) and in 2016-2019 - 19.6% and 17.4% (p NS).
Rate of 25(OH)D <12 ng/mL was 13.2% in WS-born and 6.8% in SA-born, p=0.009. In 2012-2015 it was, respectively, 22.0% and 8.1% (p=4E-5) and in 2016-2019 - 6.4% and 6.0% (p NS).
Increase of 25(OH)D in WS-born and drop of rates of 25(OH)D <20 ng/mL and <12 ng/mL are highly significant (p <E-500, p=2E-8 and p=6E-7, respectively). The study demonstrated that WS-born Latvian children have low 25(OH)D during the first year of life with slight decrease visible for at least another year, similar to other seasonal countries.
Dramatic progress in dealing with the problem has been achieved in recent years. The results show that overall 25(OH)D level in infants has risen considerably and the effect was most prominent in WS-born.
- 3.4. Other publications in conference proceedings (including local)