Weight gain is a well-known risk factor for the development of sleep-disordered breathing (SDB), and there is some evidence that weight loss can lead to improvement in SDB. Data from the Sleep Heart Health Study indicate that even modest changes in weight can be significant, especially in men.
The study included 2968 men and women (mean age, 62 years). After 5 years, those who had gained weight were more likely to have an increase in the Respiratory Disturbance Index (RDI), as assessed by polysomnography. For a given increase in weight, RDI was more likely to increase in men than in women. This finding could not be accounted for by differences in baseline weight, waist circumference, age, or ethnicity.
The increase in RDI associated with weight gain was more pronounced than the decrease in RDI associated with weight loss. In addition, the reduction in RDI accelerated with extreme weight gain, particularly in men who were already overweight.
Although the association was not as strong in women as in men, the authors say that the role of obesity in SDB should not be minimized in women.