Association of hypertension and sleep-disordered breathing

To our knowledge, the association between sleep-disordered breathing (SDB) and hypertension has not been evaluated in subjects from the general population with a wide age range while adjusting for the possible confounding factors of age, body mass index, sex, menopause and use of hormone replacement therapy, race, alcohol use, and smoking.

In the first phase of this study, we interviewed 4364 men and 12,219 women, aged 20 to 100 years. In the second phase of this study, 741 men and 1000 women, previously interviewed, were selected based on the presence of risk factors for SDB (snoring, daytime sleepiness, obesity, hypertension, and, for women, menopause). Each subject selected for the second phase of the study provided a comprehensive history, underwent a physical examination, and was evaluated for 1 night in the sleep laboratory. In terms of severity of SDB, 4 groups were identified: moderate or severe (obstructive apnea/hypopnea index > or =15.0), mild (snoring and an obstructive apnea/hypopnea index of 0.1-14.9), snoring, and no SDB, the control group.

Sleep-disordered breathing was independently associated with hypertension when potential confounders were controlled for in the logistic regression analysis. The strength of this association decreased with age and was proportional to the severity of SDB. In the best-fitted model, neither sex nor menopause changed the relationship between hypertension and SDB.

In the results of this study, SDB, even snoring, was independently associated with hypertension in both men and women. This relationship was strongest in young subjects, especially those of normal weight, a finding that is consistent with previous findings that SDB is more severe in young individuals.