SUMMARYThis cross-sectional study aimed to investigate whether body fat distribution, physical activity levels and dietary intakes are associated with insomnia and/or obstructive sleep apnea among overweight middleaged men. Participants were 211 Finnish men aged 30-65 years. Among the 163 overweight or obese participants, 40 had insomnia only, 23 had obstructive sleep apnea only, 24 had comorbid insomnia and obstructive sleep apnea and 76 were without sleep disorder. The remaining 48 participants had normal weight without sleep disorder. Fat mass, levels of physical activity and diet were assessed by dual-energy X-ray densitometry, physical activity questionnaire and 3-day food diary, respectively. Among the overweight participants, we found that: (i) groups with sleep disorders had higher fat mass in trunk and android regions than the group without sleep disorder (P = 0.048-0.004); (ii) the insomnia-only group showed a lower level of leisure-time physical activity (436.9 versus 986.5 MET min week À1 , P = 0.009) and higher intake of saturated fatty acids (14.8 versus 12.7 E%, P = 0.011) than the group without sleep disorder; and (iii) the comorbid group had a lower level of leisure-time physical activity (344.4 versus 986.5 MET min week À1 , P = 0.007) and lower folate intake (118.9 versus 152.1 lg, P = 0.002) than the group without sleep disorder, which were independent of body mass index. The results suggest that central obesity is associated with insomnia and/or obstructive sleep apnea. In addition, low levels of leisure-time physical activity and poor dietary intakes are related to insomnia or comorbid insomnia and obstructive sleep apnea among overweight men.
IN TROD UCTI ONSleep disorders such as insomnia and obstructive sleep apnea (OSA) have become a significant health issue worldwide. The prevalence of insomnia has been estimated as 6-7% among the US and European populations (Ohayon, 2002;Wittchen et al., 2011), while more than 30% of the population may suffer at least one symptom related to insomnia (Ohayon, 2002). In Finland, the prevalence of diagnosed insomnia is 11.7%, which is 1.5-2 times higher than other European countries (Ohayon and Partinen, 2002). OSA is another sleep disorder with increasing prevalence, which affects 3-17% American adults in different age and gender groups, and is most observed commonly among men from middle to old age (Peppard et al., 2013). The prevalence of OSA is approximately 8% among Finnish population (Kronholm et al., 2009). Insomnia and OSA also often exist as comorbidity (Luyster et al., 2010).An increasing number of studies have shown the association between obesity and sleep disorders. One study Sleep and body fat suggests that obese individuals are 50% more likely to suffer insomnia than participants of normal weight, thus obesity is regarded as a risk factor for insomnia (Singareddy et al., 2012). The association between obesity and OSA is more widely recognized (Punjabi, 2008). More than two-thirds of individuals with OSA are obese (Punjabi, 2008;Vgontzas et...