RESUMO
OBJECTIVE: This study aimed to verify vitamin D concentration in children and adolescents during the seasons of the year and to compare vitamin D concentration between children engaged in outdoor activities and those engaged in indoor activities. METHODS: This is a cross-sectional study with a sample of 708 children and adolescents (aged 6-18 years), excluding 109 (16 were over 19 years old; 39 had a disease that required continuous treatment; 20 were on continuous medication; and 34 had no vitamin D data), ending with 599. The plasma concentration of 25-hydroxyvitamin D2 was measured with commercial kits following manufacturer instructions. RESULTS: Participants who engaged in outdoor activities, as well as those who had data collected during summer and spring, had higher levels of vitamin D. According to the Poisson regression, the proportion of participants with inadequate levels of vitamin D was greater in the participants whose vitamin D was measured during spring (PR 1.15, 95%CI 1.03-1.29) and winter (PR 1.18, 95%CI 1.05-1.32). Also, a greater proportion of inadequate vitamin D was observed for those engaged in indoor activities (PR 1.08, 95%CI 1.01-1.15). CONCLUSIONS: Participants who measured the vitamin during the summer and autumn had a lower prevalence of hypovitaminosis D. Even in regions with high solar incidence throughout the year, vitamin D levels can vary significantly during the period's seasons.
Assuntos
Deficiência de Vitamina D , Vitamina D , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Luz Solar , Estudos Transversais , Brasil/epidemiologia , Vitaminas , Deficiência de Vitamina D/epidemiologiaRESUMO
Abstract Objective: This study aimed to verify vitamin D concentration in children and adolescents during the seasons of the year and to compare vitamin D concentration between children engaged in outdoor activities and those engaged in indoor activities. Methods: This is a cross-sectional study with a sample of 708 children and adolescents (aged 6-18 years), excluding 109 (16 were over 19 years old; 39 had a disease that required continuous treatment; 20 were on continuous medication; and 34 had no vitamin D data), ending with 599. The plasma concentration of 25-hydroxyvitamin D2 was measured with commercial kits following manufacturer instructions. Results: Participants who engaged in outdoor activities, as well as those who had data collected during summer and spring, had higher levels of vitamin D. According to the Poisson regression, the proportion of participants with inadequate levels of vitamin D was greater in the participants whose vitamin D was measured during spring (PR 1.15, 95%CI 1.03-1.29) and winter (PR 1.18, 95%CI 1.05-1.32). Also, a greater proportion of inadequate vitamin D was observed for those engaged in indoor activities (PR 1.08, 95%CI 1.01-1.15). Conclusions: Participants who measured the vitamin during the summer and autumn had a lower prevalence of hypovitaminosis D. Even in regions with high solar incidence throughout the year, vitamin D levels can vary significantly during the period's seasons.
Resumo Objetivo: Verificar a concentração de vitamina D em crianças e adolescentes durante as estações do ano e comparar essa concentração entre crianças praticantes de atividades ao ar livre e aquelas praticantes de atividades em ambiente fechado. Métodos: Trata-se de estudo transversal com amostra de 708 crianças e adolescentes (seis a 18 anos), excluindo-se 109, pois 16 eram maiores de 19 anos; 39 tinham doença que exigia tratamento contínuo; 20 estavam em uso de medicação contínua; e 34 não tinham dados de vitamina D. Terminou-se, assim, com 599 pacientes. A concentração plasmática de 25-hidroxivitamina D2 foi medida com kits comerciais, seguindo as instruções do fabricante. Resultados: Os participantes que realizaram atividades ao ar livre, assim como aqueles que tiveram dados coletados durante o verão e a primavera, apresentaram níveis mais elevados de vitamina D. De acordo com a regressão de Poisson, a proporção de participantes com níveis inadequados de vitamina D foi maior naqueles cuja medição foi realizada durante a primavera (razão de prevalência — RP 1,15, intervalo de confiança — IC95% 1,03-1,29) e o inverno (RP 1,18, IC95% 1,05-1,32). Além disso, maior proporção de vitamina D inadequada foi observada para aqueles envolvidos em atividades internas (RP 1,08, IC95% 1,01-1,15). Conclusões: Participantes que mediram a vitamina durante o verão e o outono tiveram menor prevalência para hipovitaminose D. Mesmo em regiões com alta incidência solar ao longo do ano os níveis de vitamina D podem variar significativamente durante as estações.