Influence of physical activity and television-watching time on asthma and allergic rhinitis among young adolescents: preventive or aggravating?

Background: Related to exercise hypothesis, the aim of the present study was to explore the influence of physical activity on asthma and allergic rhinitis in a developing country where publicity campaigns about the benefits of exercise are scarce. Methods: The analysed data were self-reported and obtained through the standardized International Study of Asthma and Allergies in Childhood Phase Three written questionnaires completed by 3026 adolescents 13/14 year old in Skopje (Republic of Macedonia). Vigorous physical activity and television-watching time-both unadjusted and adjusted for confounding factors-were used as variables for analysis. Odds ratios (OR, 95 % Cl) in binary logistic regression were employed for statistic analysis of the data. Results: Vigorous physical activity both <= 3 times and 1-2 times per week was associated with an increased risk of current wheeze (aOR: 1.66; 1.08-2.55; p = 0.020 and aOR: 1.70; 1.23-2.36; p = 0.001, respectively), speech-limiting wheeze (aOR: 3.15; 1.13-8.77; p=0.028 and aOR: 4.62; 2.22-9.62; p=0.000, respectively) and exercise-induced wheeze (aOR: 2.72; 1.93-3.83; p = 0.000 and aOR: 4.01; 3.12-5.14; p = 0.000, respectively). Frequent physical activity was positively associated only with current allergic rhinitis symptoms (aOR: 1.40; 1.04-1.90; p = 0.029). Television watching 3 hours a day increased the risk of current wheeze (aOR: 1.34; 1.01-1.77; p = 0.042) and exercise-induced wheeze (aOR: 1.32; 1.05-1.65; p = 0.016). Conclusion: The findings support the aggravating role of sedentary regimen and poor physical fitness on asthma symptoms, but not on allergic rhinitis. Physical activity may trigger asthma symptoms when physical fitness is poor and asthma is not controlled.