Sleep apnea associated with HF and CHD in men
MedWire News: Men with obstructive sleep apnea (OSA) have a greater risk for heart failure (HF) and coronary heart disease (CHD) than women with the breathing disorder, a US study reports.
Daniel Gottlieb (Boston University School of Medicine, Massachusetts) and colleagues say that their findings may reflect the "later age of onset of OSA in women than in men... thus at baseline, women may have had less cumulative exposure to OSA than men with a similar apnea-hypopnea index (AHI)."
They add: "It is also possible, however, that there are differences between men and women in the physiological response to OSA."
In 1995-1998, the team recruited 4422 male (n=1927) and female (n=2495) healthy participants aged 40 years or more.
All participants underwent polysomnography at baseline, from which OSA severity was determined by an AHI score, defined as the average number of apnea and hypopnea episodes per hour of sleep.
Over a median follow-up period of 8.7 years, 308 HF events and 473 incident CHD events, defined as first myocardial infarction (MI, n=185), coronary revascularization (n=212), or CHD-related death (n=76) occurred.
As described in the journal Circulation, analysis showed that men had more severe OSA than women, with an average AHI score of 6.2 and 2.7, respectively.
After adjustment for age, race, smoking status, and body mass index, a positive association was found between OSA severity and incident CHD among men but not women. For an AHI score of ≥30, incident CHD risk increased by a significant 45% (p=0.046) and nonsignificant 33% among men and women of all ages, respectively, compared with those with an AHI score <5.
This increase in incident CHD risk was greatest for men aged ≤70 years, at 68%. After adjustment for HF risk factors such as race and hypertensive medication use, OSA severity was also positively associated with HF among men but not women, with AHI score ≥30 versus <5 associated with a significant 58% (p=0.02) and nonsignificant 19% increase in HF risk, respectively.
The association between HF and OSA severity in men was maintained irrespective of age.
Gottlieb et al conclude: "The present study provides prospective evidence that OSA is associated with an increase in the risk for incident HF in community-dwelling middle-aged and older men and is consistent with a modest increase in CHD risk in middle-aged men."
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By Lauretta Ihonor