Climate change linked to dangerous sleep apnea

Sleep apnea is expected to become more common and severe as a result of global warming, leading to increased health and economic burdens worldwide, according to sleep experts from Flinders University.

Published in Nature Communications, the study titled “Global warming may increase the burden of obstructive sleep apnea” reveals that rising temperatures are linked to the worsening of obstructive sleep apnea (OSA). Under the most likely climate change scenarios, the societal burden of OSA is projected to double in most countries over the next 75 years.

Lead author and sleep expert, Dr. Bastien Lechat, from FHMRI Sleep Health, explains that this study is the first of its kind to explore how global warming could impact breathing during sleep and affect global health, well-being, and economy.

“This study sheds light on how environmental factors such as climate can influence health by examining the relationship between ambient temperatures and OSA severity,” says Dr. Lechat.

“We were surprised by the significant association between ambient temperature and OSA severity. Higher temperatures were found to increase the likelihood of experiencing OSA by 45% on a given night.”

“The findings varied by region, with European countries showing higher rates of OSA with rising temperatures compared to Australia and the United States, possibly due to differences in air conditioning usage.”

Sleep apnea, a condition that disrupts breathing during sleep, affects nearly 1 billion people globally. If left untreated or severe, it can increase the risk of various health issues such as dementia, hypertension, cardiovascular disease, anxiety, depression, reduced quality of life, traffic accidents, and mortality.

In Australia alone, the economic cost associated with poor sleep, including sleep disorders like OSA, is estimated at $66 billion per year.

The study analyzed sleep data from over 116,000 individuals globally using an FDA-cleared under-mattress sensor to estimate OSA severity. Each user’s sensor recorded data from approximately 500 nights of sleep, which was then compared with detailed 24-hour temperature information from climate models.

Health economics modeling was conducted using disability-adjusted life years, a measure used by the World Health Organization to assess the impact of illness, injury, and premature mortality. This was done to quantify the well-being and societal burden resulting from the increased prevalence of OSA due to rising temperatures under various climate scenarios.

“Our modeling allows us to estimate the impact of the rising OSA prevalence on society in terms of well-being and economic loss,” explains Dr. Lechat.

“The increase in OSA prevalence in 2023 due to global warming was associated with a loss of approximately 800,000 healthy life years across the 29 countries studied.”

“This number is comparable to other medical conditions such as bipolar disorder, Parkinson’s disease, or chronic kidney diseases.”

Similarly, the estimated total economic cost was around $98 billion USD, including $68 billion USD from well-being loss and $30 billion USD from workplace productivity loss.

“Our findings emphasize that without significant policy action to mitigate global warming, the burden of OSA may double by 2100 due to rising temperatures,” adds Dr. Lechat.

Senior researcher on the paper, Professor Danny Eckert, notes that while the study is one of the largest of its kind, it was skewed towards high socio-economic countries and individuals likely to have access to better sleeping conditions and air conditioning.

“This potential bias may have led to an underestimation of the true health and economic costs,” says Professor Eckert.

Aside from underscoring the serious threat of climate change to human health and well-being, the study underscores the importance of developing effective interventions for diagnosing and managing OSA.

“Increased rates of diagnosis and treatment can help us mitigate the adverse health and productivity consequences of climate-related OSA,” states Professor Eckert.

“Moving forward, we aim to design intervention studies to explore strategies for reducing the impact of ambient temperatures on OSA severity and investigate the underlying physiological mechanisms linking temperature fluctuations to OSA severity.”