• Researchers followed more than 5,000 people for about 15 years
  • Those with COMISA were more likely to have hypertension, cardiovascular disease
  • Those being tested for one of the disorders should be tested for the other: Researchers

How can two of the most common sleep disorders affect the mortality of those who suffer from them? Those with co-occurring insomnia and obstructive sleep apnea (OSA) are 47% more likely to die compared to those who don't have the conditions, a new study has found.

"Increased mortality" has been seen in people with insomnia and those with OSA, researchers noted in their new study, published in the European Respiratory Journal. These are the "two most common sleep disorders," study lead Dr. Bastien Lechat said in the Flinders University news release. However, when both conditions are present, called co-morbid insomnia and sleep apnea (COMISA), the effect of the combination on mortality risk is "unknown."

For their study, the researchers looked at 5,236 participants. Among them, 52% did not have either insomnia or OSA (control group), 3% had only insomnia, 42% had only OSA and 3% had COMISA. The participants were about 60 years old when the study began, and the researchers followed them for about 15 years. During that time, 1,210 of the participants died.

"Insomnia-alone and OSA-alone were associated with higher risk of hypertension but not cardiovascular disease compared to controls," the researchers wrote.

However, those who had COMISA were twice as likely to have high blood pressure and 70% more likely to have cardiovascular disease compared to the controls, the university noted. They also had a 47% higher risk of dying "for any reason" compared to the controls.

"The association between COMISA and mortality was consistent across multiple definitions of OSA and insomnia," the researchers noted.

According to the researchers, the results show that COMISA is associated with higher hypertension and cardiovascular disease as well as an increased risk for all-cause mortality "compared to no insomnia/OSA."

"This is the first study to assess mortality risk in participants with co-morbid insomnia and sleep apnea," Dr. Lechat said as per the news release. "Given that these people are at higher risk of experiencing adverse health outcomes, it is important that people undergoing screening for one disorder should also be screened for the other."

Apart from looking further into the causes of the higher-mortality risk in people with COMISA, the researchers also stressed the need to make sure that insomnia and sleep apnea treatments are effective for this group of people, the university noted.

Millions of Americans suffer from some form of sleep disorder like insomnia each year. Pixabay (CC0)