Longitudinal study of moderate weight change and sleep-disordered breathing.

CONTEXT: Excess body weight is positively associated with sleep-disordered breathing (SDB), a prevalent condition in the US general population. No large study has been conducted of the longitudinal association between SDB and change in weight.
OBJECTIVE: To measure the independent longitudinal association between weight change and change in SDB severity.
DESIGN: Population-based, prospective cohort study conducted from July 1989 to January 2000. SETTING AND PARTICIPANTS: Six hundred ninety randomly selected employed Wisconsin residents (mean age at baseline, 46 years; 56% male) who were evaluated twice at 4-year intervals for SDB. MAIN OUTCOME MEASURES: Percentage change in the apnea-hypopnea index (AHI; apnea events + hypopnea events per hour of sleep) and odds of developing moderate-to-severe SDB (defined by an AHI > or =15 events per hour of sleep), with respect to change in weight.
RESULTS: Relative to stable weight, a 10% weight gain predicted an approximate 32% (95% confidence interval [CI], 20%-45%) increase in the AHI. A 10% weight loss predicted a 26% (95% CI, 18%-34%) decrease in the AHI. A 10% increase in weight predicted a 6-fold (95% CI, 2.2-17.0) increase in the odds of developing moderate-to-severe SDB.
CONCLUSIONS: Our data indicate that clinical and public health programs that result in even modest weight control are likely to be effective in managing SDB and reducing new occurrence of SDB.