Summary: People who suffer from insomnia in conjunction with sleep apnea are more likely to experience heart problems and are 50% more likely to die than those without the conditions.
Source: Flinders University
People who suffer from both insomnia and obstructive sleep apnoea are more likely to suffer from heart problems and are almost 50% more likely to die than those without either condition, say Flinders University researchers, who advise people being tested for one of the disorders be tested for the other.
“Insomnia and obstructive sleep apnoea are the two most common sleep disorders, affecting 10 to 30% of the population, but people can often suffer from both at the same time,” says Dr Bastien Lechat from Flinders Health and Medical Research Institute: Sleep Health.
“Previously, little was known about the impact of co-morbid insomnia and obstructive sleep apnoea (COMISA) but what we did know is that for people with both conditions, health outcomes are consistently worse than those with neither condition or those with either condition alone.”
Now, in a new study published in the European Respiratory Journal, Flinders researchers have studied a large US-based dataset of over 5000 people to understand the risks of COMISA.
The participants, aged around 60 years of age at the beginning of the study and 52% female, were followed for approximately 15 years, with 1210 people dying during that time.
The results suggested that participants with COMISA were two times more likely to have high blood pressure and 70% more likely to have cardiovascular disease than participants with neither insomnia nor sleep apnoea.
The study also showed participants with COMISA had a 47% increased risk of dying (for any reason) compared to participants with no insomnia or sleep apnoea, even when other factors known to increase mortality were taken into account.
“This is the first study to assess mortality risk in participants with co-morbid insomnia and sleep apnoea,” says Dr Lechat, who led the research.
“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.”
While further research is needed to investigate what might be causing the higher mortality risk for those with COMISA, researchers say further investigation is also warranted to ensure treatments are working effectively.
“Specific treatments may be needed for people with co-occurring disorders so it’s important we examine the efficacy of insomnia and sleep apnoea treatments in this specific population,” says Dr Lechat.
The Adelaide Institute for Sleep Health at Flinders University is continuing to conduct research to understand the reasons that insomnia and sleep apnoea co-occur so frequently, and to develop more effective treatment approaches.
Increased mortality has been reported in people with insomnia and in those with obstructive sleep apnoea (OSA). However, these conditions commonly co-occur and the combined effect of co-morbid insomnia and sleep apnoea (COMISA) on mortality risk is unknown. This study used Sleep Heart Health Study (SHHS) data to assess associations between COMISA and all-cause mortality risk.
Insomnia was defined as difficulties falling asleep, maintaining sleep, and/or early morning awakenings from sleep ≥16 times a month and daytime impairment. OSA was defined as an apnoea-hypopnoea index ≥15 events/h sleep. COMISA was defined if both conditions were present. Multivariable adjusted Cox proportional hazard models were used to determine the association between COMISA and all-cause mortality (n=1210) over 15 years of follow-up.
5236 participants were included. 2708 (52%) did not have insomnia/OSA (control), 170 (3%) had insomnia-alone, 2221 (42%) had OSA-alone, and 137 (3%) had COMISA. COMISA participants had a higher prevalence of hypertension (ORs [95%CI]; 2.00 [1.39, 2.90]) and cardiovascular disease compared to controls (1.70 [1.11, 2.61]). Insomnia-alone and OSA-alone were associated with higher risk of hypertension but not cardiovascular disease compared to controls. Compared to controls, COMISA was associated with a 47% (HR, 95% CI; 1.47 (1.06, 2.07)) increased risk of mortality. The association between COMISA and mortality was consistent across multiple definitions of OSA and insomnia.
Co-morbid insomnia and sleep apnoea was associated with higher rates of hypertension and cardiovascular disease at baseline, and an increased risk of all-cause mortality compared to no insomnia/OSA.