Global warming may increase the burden of obstructive sleep apnea.

High ambient temperatures are associated with reduced sleep duration and quality, but effects on obstructive sleep apnea (OSA) severity are unknown. Here we quantify the effect of 24 h ambient temperature on nightly OSA severity in 116,620 users of a Food and Drug Administration-cleared nearable over 3.5 years. Wellbeing and productivity OSA burden for different levels of global warming were estimated. Globally, higher temperatures (99 vs. 25; 27.3 vs. 6.4 °C) were associated with a 45% higher probability of having OSA on a given night (mean [95% confidence interval]; 1.45 [1.44, 1.47]). Warming-related increase in OSA prevalence in 2023 was estimated to be associated with a loss of 788,198 (489,226, 1,087,170) healthy life years (in 29 countries), and a workplace productivity loss of 30 (21 to 40) billion United States dollars. Scenarios with projected temperatures ≥1.8 °C above pre-industrial levels would incur a further 1.2 to 3-fold increase in OSA burden by 2100.