To sleep, perchance to golf

Low energy levels in patients with hypertension and depression
may actually be caused by sleep apnea

By Owen Dyer

Chris Avery, 52, is a chronic complainer whose only joy in life is his weekend golf game. So when he found he was sleeping in nowadays instead of hitting the golf course on Sundays, he knew there was a serious problem. He turned to his doctor for help with his fatigue and was sent home with antidepressants. But was depression really the problem, or was the underlying cause of Mr Avery's fatigue going undiagnosed?

According to a US study, patients who received both antihypertensives and antidepressants were up to 18 times more likely to eventually be diagnosed with obstructive sleep apnea (OSA). "What this tells us is that patients are routinely treated for the symptoms and complications of OSA while the underlying pathophysiologic condition proceeds unabated," said Dr Robert Farney, Medical Director of the LDS Hospital Sleep Disorders Center in Salt Lake City, and principal investigator of the study in the April edition of Chest.

Dr Farney believes hypertension and chronic fatigue, which are possibly the most common conditions for which patients seek medical attention, are the cardinal elements of OSA. Dr Farney and his colleagues analyzed the computer archives of 212,972 patients for prescriptions for antihypertensives, antidepressants, and diagnoses of OSA. The overall prevalence of diagnosed OSA in men was 0.8% in the 20-39 age group, 2.8% in the 40-59 age group and 3.2% in the over-60s. In women, OSA was almost exactly half as frequent as in men, a finding that's in line with existing research.

The database was divided into two groups, one group comprising patients who'd been prescribed both antihypertensives and antidepressants, and the other of patients who had not. Among the under-40s, patients in the first group were 17 to 18 times more likely to have a diagnosis of OSA than people in the second group. Among older patients, the association was less marked; but naturally, antihypertensive use is much more widespread in this age group.

"Depression or chronic fatigue syndrome is readily diagnosed in patients with the primary complaint of fatigue," said Dr Farney. Accordingly, "these patients are frequently treated with antidepressant medications although unrecognized sleep apnea might be present."

The authors aren't suggesting that antihypertensives or antidepressants cause sleep apnea. Rather, they believe sleep apnea may be causing chronic fatigue that is usually blamed on depression. Sleep apnea is common in those who are overweight or physically inactive, so it's no surprise it frequently goes hand in hand with hypertension.

It's estimated that the diagnosis of sleep apnea is missed in 82% of men and 93% of women with moderate-to-severe OSA. The study is significant, say researchers, because practising clinicians should be alerted by therapy with these medications to the possibility that easily treated sleep apnea may be the underlying cause.