Thermosomnia: Consequences of rising temperatures and climate change for clinical sleep disorders.

Elevated ambient temperatures harm global sleep health, yet research into their effects on clinical sleep disorders is sparse and poorly synthesised. We review relevant literature and introduce the term "thermosomnia"-a portmanteau of thermo (heat/temperature) and somnia (sleep)-to characterise the multifaceted impact of high and rising ambient temperature on clinical sleep disorder outcomes. We address five key areas: (1) effects of elevated ambient temperatures on sleep disorder prevalence and symptom severity; (2) implications of thermosomnia for the safe and effective treatment of clinical sleep disorders; (3) potential mechanisms of thermosomnia; (4) social determinants of thermosomnia; and (5) the worsening of thermosomnia due to anthropogenic climate change. We highlight literature showing that elevated ambient temperatures are associated with exacerbated obstructive sleep apnoea and greater nighttime insomnia symptoms, and threaten treatment effectiveness via reduced adherence. Consequently, elevated temperatures likely compound existing risks associated with clinical sleep disorders. Select demographic groups are disproportionately susceptible to temperature-related sleep disorder effects, and climate change will likely exacerbate thermosomnia and increase global disparities in clinical sleep health. This review identifies an urgent need for research to inform equitable clinical and public health responses to rising ambient temperatures and to mitigate the growing burden of thermosomnia.