Objective: To examine the associations between sleep problems and major weight gain during a 5- to 7-year follow-up among middle-aged women and men.
Methods: The Helsinki Health Study prospective cohort baseline survey data from 2000 to 2002 (n = 8960, response rate 67%) among 40- to 60-year-old municipal employees and follow-up survey data from 2007 (n = 7332, response rate 83%) were used. Logistic regression analysis was used to examine the association between the four-item Jenkins Sleep Questionnaire and major weight gain of 5 kg or more over a 5- to 7-year follow-up.
Results: Half of the participants reported at least occasional sleep problems, whereas 13% of women and 17% of men reported no such problems at baseline. The frequency of sleep problems varied by item. Frequent sleep problems were reported by 20% of women and 17% of men. Major weight gain was reported by 25% of women and 24% of men. Trouble falling asleep (odds ratio (OR) 1.65; 95% confidence interval (CI) 1.22, 2.22), waking up several times per night (OR 1.49; 95% CI 1.22, 1.81) and trouble staying asleep (OR 1.41; 95% CI 1.13, 1.75) were associated with major weight gain during the follow-up in women but not in men. In contrast, waking up tired was unassociated with weight gain. The summary measure of the four items was also associated with weight gain in women. Adjusting for baseline body mass index, physical health, health behaviour, marital status, education, work arrangements and sleep duration had only minor effects on the above associations. Adjusting for common mental disorders at baseline, the associations were attenuated but remained for trouble falling asleep, waking up several times per night and trouble staying asleep. Occasional sleep problems were also associated with weight gain.
Conclusion: Sleep problems likely contribute to weight gain. To prevent major weight gain and obesity, sleep problems need to be taken into account.