ORIGINAL ARTICLE Joint effects of body mass index, exercise, and alcohol drinking on the development of snoring Soo J KIM, 1 Inkyung BAIK, 2 Jehyeong KIM, 3,4 Kihwan JUNG, 3,4 Seung H LEE, 3,5 Se J KIM 3,4 and Chol SHIN 3,4,6 1 Department of Occupational and Environmental Medicine, Ajou University School of Medicine, Suwon, and 2 Department of Food and Nutrition, College of Natural Sciences, Kookmin University, and 3 College of Medicine, Korea University, Seoul, and Departments of 4 Internal Medicine and 5 Otolaryngology-Head and Neck Surgery, Korea University Ansan Hospital, and 6 Institute of Human Genomic Study, Korea University Ansan Hospital, Ansan, Korea Abstract Obesity is consistently reported to have a positive association with the development of habitual snoring. Whether lifestyle factors modify the association between body weight and the future risk of snoring has not been examined. In a prospective cohort study, we evaluated the association of lifestyle factors and body mass index (BMI) with the development of snoring. The study population (497 men and 670 women aged 40–69 years) were drawn from an ongoing population-based cohort. At baseline, all participants were free of cardiovascular disease and snoring at night. Information on lifestyle factors and snoring frequencies was obtained from interviewer-based questionnaires. During the 4-year follow-up, 533 participants reported new onset snoring. After adjusting for age, sex, and other potential risk factors, overweight persons with a BMI of 25 kg/m 2 were found to have a 48% excess (95% confidence interval, 10% to 100%) in the odds of developing snoring compared with those with a BMI of <23 kg/m 2 . In particular, we found that alcohol drinking and frequent exercise modify the association between BMI and the development of snoring; alcohol drinkers showed a stronger association than abstainers and persons who did not frequently exercise showed a stronger association than those exercising 4 days per week. We observed that even overweight persons who drink alcohol or do not exercise frequently had a higher chance of becoming snorers. Further evaluations are warranted to confirm whether abstaining from alcohol and frequent exercise can help prevent future snoring. Key words: alcohol, body mass index, exercise, sleep-disordered breathing, smoking. INTRODUCTION Snoring is a prevalent sleep-associated disorder in the general population 1 and is reportedly associated not only with minor health problems, such as excessive daytime sleepiness 2 and morning headaches, 3 but also with the risk of more serious diseases, including chronic bronchitis, hypertension, and cardiovascular disease, 4–10 and mortality. 11 A number of epidemiologic studies have sought to identify determinants of the development of snoring and found a positive association of body weight with prevalence and incidence of snoring. 12–16 Among these studies, furthermore, some have explored whether lifestyle factors, such as cigarette smoking, alcohol drinking, and exercise, play a role in the development of Correspondence: Dr Chol Shin MD, PhD, Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Korea University Ansan Hospital, 516, Gojan-1-dong, Danwon-gu, Ansan, Gyeonggi-do, 425-707, Korea. Email: shinchol@pol.net Accepted for publication 31 January 2010 Sleep and Biological Rhythms 2010; 8: 144–150 doi:10.1111/j.1479-8425.2010.00441.x 144 © 2010 The Authors Journal compilation © 2010 Japanese Society of Sleep Research