Risk factors for acute respiratory tract illness in military conscripts

Background and objective: Acute respiratory tract infections are the leading cause of missed service days among military conscripts. The aim of this study was to identify factors that possibly predicted and contributed to frequent respiratory tract infections among military conscripts. Methods: Data on episodes of respiratory illness were collected during the 180-day period of military service in Kajaani, Finland, between July 2004 and July 2005. Results: There were 518 military conscripts recruited, 124 of whom had a diagnosis of asthma. Conscripts with frequent (three or more) infections were more often atopic or suffered from allergic rhinitis or asthma. Overweight (BMI >= 25 kg/m(2)) and previous respiratory tract infections were the two independent risk factors for frequent respiratory infections. Overall, 4.8% of those who had no risk factors, 10. 3% of those with one risk factor and 35.7% of those with two risk factors suffered from frequent respiratory infections (P for trend < 0.001). Conclusions: Overweight (BMI >= 25 kg/m(2)) and previous respiratory tract infections are risk factors for frequent respiratory tract infections in young men during military service.