It’s been estimated that nearly 1 billion people worldwide have mild to severe obstructive sleep apnea (OSA). A study published in BMJ Open Respiratory Research has shown that people who have OSA are nearly twice as likely to experience sudden death from cardiovascular complications (e.g. hypertension, coronary artery disease, congestive heart failure, arrhythmias) or all-cause sudden death compared to those who do not have the condition (BMJ Open Respir Res. 2021;8:e000656).
Researchers at Penn State Health performed a literature review of 22 studies published through January 1, 2020, comprising more than 42,000 patients (mean age 62 years; 64% male) from five continents (North America, Europe, Australia, Asia, South America, excluding Africa and Antarctica). Observational studies that reported rates of sudden death in individuals with OSA and studies that reported the rates of sudden death in both patients with and without OSA were included.
The researchers found that OSA was associated with all-cause sudden death, with a risk ratio of 1.74 (95% CI: 1.44 to 2.10) and cardiovascular mortality, with a risk ratio of 1.94 (95% CI: 1.39 to 2.70). There was a marginally significant dose/response relationship between the severity of the OSA and the risk of death: mild OSA (risk ratio 1.16), moderate OSA (risk ratio 1.72), and severe OSA (risk ratio 2.87). A meta-regression analysis showed that older age was a significant contributing factor. Analysis by continent showed significant pooled risk ratios for North America, Europe, and Australia; risk ratios were not significant for Asia and South America. Even after adjusting for possible publication bias, the estimates for the connection between OSA and sudden death remained significant.
“Obstructive sleep apnea is a common condition that can have fatal consequences,” said co-author Dr. John S. Oh, MD, assistant professor in the department of surgery at the Penn State Health Milton S. Hershey Medical Center in Hershey, Penn., in a press release. “This is something that many patients don’t consider when they’re diagnosed with the condition. Hopefully, our research will bring more attention to its prevention and treatment.”