Comparative analysis of pathogenetic predictors of weight gain in children and adolescents based on age and gender

Objective — to investigate the cause­effect relationship between exogenous and endogenous factors contributing to obesity and to identify age and gender differences through a comprehensive examination and questionnaire survey of Ukrainian school­aged children. Materials and methods. A cohort of 628 randomly selected students from secondary schools in Ternopil was studied and a written questionnaire was administered to students and their parents. A total of 616 completed valid questionnaires were collected and analyzed. The mean age of the respondents was (13.7 ± 0.08) years. There were 337 boys (54.8 %) and 279 girls (45.2 %). The anthropometric and questionnaire data were analyzed using the method of medical statistics with programs Statistica 12.0 (StatSoft Inc., 193, USA) and Microsoft Excel 2013. Results and discussion. Overweight children, irrespective of age and gender, more frequently have overweight close relatives with hypertension and diabetes mellitus compared to the general Ukrainian population. A list of additional predisposing factors for obesity in schoolchildren have been identified. Sleeping less than 6 hours per night increases the risk of obesity nearly fourfold (RR = 3.82, 95% CI = 1.741—6.328). Prolonged screen­time (more than 5 hours) on weekdays increases the risk of obesity by one and a half times (RR = 1.69, 95 % CI = 0.938—2.894) and at weekends by two times (RR = 1.99, 95 % CI = 1.201­3.257). Lack of physical activity (less than 2 hours per week) doubles the risk of obesity (RR = 2.06, 95 % CI = 1.229—3.235). On the other hand, a number of factors have a significant preventive effect and can be recommended for the weight gain prophylactics. In particular, limiting screen­time to less than 2 hours per day on weekdays reduces the risk of obesity by 75% (RR = 0.25, 95 % CI = 0.120—0.487) and by 47 % at weekends (RR = 0.53, 95 % CI = 0.304—0.894). Sufficient night rest (more than 8 hours) reduces the risk of obesity by 52% (RR = 0.48, 95 % CI = 0.291—0.791) and sufficient physical activity (at least 20 minutes 5 days a week) reduces by 68 % (RR = 0.32, 95 % CI = 0.143—0.667). Perinatal factors, such as birth weight and breastfeeding, are much less significant than further children’s lifestyle. The frequency of physical activity during the week was found to have a greater effect on body proportions in boys and in late school­age children. Prolong night sleep prevents weight gain in both girls and boys equally, especially in late adolescent. the duration of screen­time on weekdays and weekends is directly related to weight gain in schoolchildren, regardless of age or gender. Conclusions. Having close overweight relatives is the most significant factor increasing the risk of BMI in school­age children by 12.5 times. The body composition of Ukrainian schoolchildren is more strongly influenced by daily routines and behavior patterns, namely the intensity of daily physical activity, the duration of night sleep and the screen­time, than on birth weight or the duration of breastfeeding in the first year of life. It is advisable to take into account the presence of genetic predisposition, age and gender, and to assess the child’s daily routine and habits, in personification of recommendations.