Good Sleep is Good for the Heart

Treating sleep apnea may reduce risk of heart attack

(RxWiki News) Treating sleep apnea does more than ensure you get enough good quality sleep. It might also help protect you from getting a heart attack.

A recent study revealed that changes to the heart caused by untreated sleep apnea, which have a similar impact on the body as high blood pressure, were almost completely reversed after six months of apnea treatment.

"Get treatment if you have sleep apnea."

Lead author Gregory Lip, M.D., a researcher at the University of Birmingham Center for Cardiovascular Sciences in Birmingham in England, and his colleagues compared three groups of patients, including one group of 40 people with moderate to severe sleep apnea.

They compared cardiovascular data from these patients to a group of 40 people with high blood pressure and a group of 40 healthy people.

Even though the sleep apnea patients had only a slightly higher than typical blood pressure, the abnormalities researchers observed in the apnea patients' hearts and its ability to pump were similar to the abnormalities seen in the hypertensive patients.

The hearts of the sleep apnea patients tended to be larger and have thickening in their walls. They also showed a lower pumping ability.

After these patients spent six months receiving treatment for their apnea in the form of continuous positive airway pressure, or CPAP, the heart irregularities returned to nearly the same measurements as those of the healthy patients.

The researchers used 3-D echocardiograms and Doppler imaging of the heart muscle tissue for their observations, which provide more accurate data than past research that has shown a link between obstructive sleep apnea and problematic changes in the heart's left ventricle.

"Our findings imply that OSA could be crucial in the development of left ventricular diastolic dysfunction that can lead to heart failure and increased mortality if left untreated," Lip said.

"To the best of our knowledge, this is the first study to provide a comprehensive assessment of left ventricular structural and functional parameters using advanced echocardiograms in otherwise healthy apnea patients," he added.

Dr. William Kohler, M.D., medical director of the Florida Sleep Institute in Spring Hill, Florida, said this study adds even more weight to the building research that links severe sleep apnea to cardiovascular disease.

"It's very important for patients who have hypertension and other signs of cardiovascular disease to be evaluated for underlying possible sleep problems, including and, in particular, obstructive sleep apnea," said Kohler, who was not associated with this study.

"This particular study gives additional important proof of the significant correlation between cardiovascular disease and sleep apnea," he said.

Lip suggested a randomized trial to confirm or clarify the findings because limitations of this non-randomized, non-blinded study included the potential for observer bias and the fact that the sleep apnea patents tended to have a higher body mass index, another risk factor for cardiovascular disease.

The study appeared online March 13 in the journal Circulation: Heart Failure, a journal of the American Heart Association.

Review Date: 
March 13, 2012