Contrary to previous studies, a new research has shown that using a continuous positive airway pressure (CPAP) machine to treat obstructive sleep apnea (OSA) may not reduce the patient’s risk of developing coronary or cerebrovascular conditions.

Over 25 million Americans suffer from OSA, a disorder that causes them to stop breathing for short intervals, sometimes more than once. As they sleep, their throat muscles relax and block the airway but the CPAP machine keeps the airway open by pushing a stream of air through the nostrils.

The condition has been linked to a number of potentially life-threatening conditions like heart disease, high blood pressure, strokes and Type 2 diabetes. Craig S. Anderson, a professor of stroke neurology at the George Institute for Global Health in Sydney, and one of the leaders of the new study, explained that the older work in the field had shown that CPAP could have a positive impact on these conditions as “the epidemiological data is very strong and the biomarker data is very strong,” the Washington Post reported.

The Sleep Apnea Cardiovascular Endpoints (SAVE) study involved over 2,700 participants from seven countries, between the ages of 45 and 75. These subjects were divided into two roughly equal groups. Of these, one group was given the CPAP mask to wear but only for about 3.3 hours per night. This time was consistent with the time users utilize the mask for in the real world.

The researchers found that there was no significant impact on heart attacks and strokes for the two groups.

The reason behind this is not known but the authors of the study say that the short interval of time that the patients used the mask for was possibly not enough to affect the frequency of the cardiovascular activity.

However, the use of the CPAP machine did have a significant impact on other aspects among the subjects. As the machine reduced the daytime sleepiness, the subjects showed an improvement in mood, quality of life as well as work productivity.

The study was published in the New England Journal of Medicine and presented at European Society of Cardiology annual meeting in Rome on Sunday.