OSA patients who were treated with CPAP had significantly fewer cardiovascular disease-related deaths and cardiovascular-related events than untreated patients in a study published in the June issue of Chest, the peer-reviewed journal of the American College of Chest Physicians.

“Research has shown that patients with OSA have an increased incidence of death or events related to cardiovascular disease, particularly hypertension,” said Walter McNicholas, MD, FCCP, St. Vincent’s University Hospital, Dublin, Ireland.

“Short-term use of CPAP therapy has resulted in health and quality-of-life benefits in patients with sleep apnea, including improved daytime alertness and mental functioning," he added. "Extended CPAP therapy may have additional benefits for patients with OSA by protecting them against cardiovascular disease related to the sleep disorder.”

Long-Term Effect of CPAP on Heart Disease

Researchers from St. Vincent’s University Hospital in Dublin followed 168 patients with OSA for an average of 7.5 years to monitor the long-term effect of CPAP therapy on cardiovascular disease. They compared the number of cardiovascular-related events and deaths among the 107 patients who used CPAP therapy to the number of such occurrences among the 61 patients who never tolerated CPAP therapy or stopped using it for at least five years.

There was a significant excess of cardiovascular deaths among the untreated patients (14.8 percent) versus the CPAP group (1.9 percent) during the follow-up period.

The total number of cardiovascular events -- including death, congestive heart failure, hypertension, and stroke -- also was significantly greater in the untreated group (31 percent), compared to the CPAP group (18 percent).

There were no significant differences between the CPAP group and the untreated group in terms of age, body mass index, and cardiovascular risk factors at baseline; however, patients in the untreated group had significantly lower apnea scores and more had undergone nasal surgery prior to diagnosis of OSA.

Identify and Modify Risk Factors

“The association between OSA and cardiovascular disease is not fully understood. It is possible that the constant fluctuation in blood oxygen levels caused by OSA may contribute to arterial inflammation, blood-flow obstruction, and, eventually, increased hypertension and cardiovascular-related events,” said Dr. McNicholas.

“Through the long-term relief of OSA, patients may decrease the subtle physical effects of OSA, thereby decreasing the overall incidence of cardiovascular morbidity and mortality,” he said.

“Sleep apnea is associated with several modifiable risk factors -- including obesity, smoking, and excessive alcohol use,” said Paul A. Kvale, MD, FCCP, President of the American College of Chest Physicians.

“Although it is important to manage OSA through treatments, such as CPAP, physicians and patients must take steps to identify and modify risk factors that may be contributing to the disorder,” he noted.