Patients with with depression and AHI ≥ 30 show the greatest risk of all-cause mortality.
Research has shown the prevalence of clinical depression has been swiftly growing. Depression can have a debilitating impact on an individual’s quality of life and self-worth due to low mood, little or no interest in previously enjoyable activities, loss of appetite, and suicidal thoughts.1
Additionally, the psychiatric condition often interferes with sleep, reducing the amount of sleep that’s achieved, and diminishing the quality of sleep when it does occur. Previous evidence has linked depression with comorbid physical disorders and chronic vascular diseases like gut microbiota, inflammatory responses and oxidative stress, brain structural decline, and cardiovascular disease (CVD).
Estimates have shown depression is likely to become a significant burden as early as 2030. It’s also been identified as a key contributing factor in the escalated rate of global all-cause mortality. Like depression, obstructive sleep apnea (OSA) severely inhibits quality of sleep, and is associated with increased risk of cardiovascular disease, however, the level of this risk in patients with coexisting depression and obstructive sleep apnea has yet to be determined, investigators wrote.
A team of investigators led by Hui Liu, Respiratory and Critical Care Department, Third Affiliated Hospital of Soochow University, First People's Hospital of Changzhou, explored the relationship between cardiovascular disease and depression with comorbid obstructive sleep apnea in a post hoc analysis of a prospective study to assess the risk of cardiovascular disease morbidity and all-cause mortality in this population.
The sample for this investigation consisted of patient data from the Sleep Heart Health Study (SHHS). Liu’s team focused on the cohort of patients who received in-home polysomnography (PSG), and previously collected information on cardiovascular risk factors. Of the 6441 individuals recruited in the SHHS, consent was withdrawn by 637.
Patients were excluded if follow-up data were missing, or they had a history of myocardial infarction, stroke, revascularization, or heart failure at baseline.
Cardiovascular disease was defined as any incidence of hospitalized acute infarction, non-fatal coronary heart disease, stroke, angina, coronary artery bypass graft, and congestive heart failure (CHF) in the data from the original SHHS investigation. Cardiovascular disease-free survival time was determined based on the interval from baseline to the first cardiovascular event.
An Apnea-Hypopnea Index (AHI) score of 15 events per hour of sleep was established as the threshold of obstructive sleep apnea. Questionnaires with opposite or similar descriptions to the WHO-5 were utilized to determine depression. Patients that scored lower than 13, along with those who had a history of anti-depressant treatment were deemed as suffering from the disorder.
A total of 4918 patients were included in the analysis after exclusions with a mean age of 64.4 years, and of that, 2345 (47.7%) were men. Based on disease presence, patients were stratified into 4 categories:
With 2166 patients, the healthy group made up a large minority (44%), followed by the depression group (32.8%) with 1614 patients, 656 patients in the OSA group (13.3%), and 482 patients in the DOSA group (9.8%).
Investigators identified depression in 42.4% of patients who had obstructive sleep apnea, and a similar rate of 42.7% in those without obstructive sleep apnea. When patients with depression were measured, obstructive sleep apnea was observed in 22.9%. In patients without depression, 23.2% exhibitd obstructive sleep apnea.
Findings suggested that patients with coexisting depression and obstructive sleep apnea might be at increased risk of cardiovascular disease. The risk of all-cause mortality was greater among those with higher AHI index.
Data demonstrated the risk of cardiovascular disease in patients with depression and obstructive sleep apnea was increased compared with healthy participants. Investigators noted consistency across various definitions of obstructive sleep apnea. Of these high-risk patients, those with AHI ≥ 30 also showed an increased risk of all-cause mortality.