Hot Climate and Dry Eye Disease: Epidemiology, Pathophysiology, and Management—A Narrative Review

Abstract

Dry eye disease (DED) is a multifactorial, highly prevalent ocular surface condition affecting hundreds of millions of people globally. Environmental variables—particularly ambient temperature and relative humidity (RH)—are increasingly being recognized as significant determinants of tear film stability and DED severity. Populations residing in hot climates face a unique and compounded burden, driven by direct thermal effects on the tear film, secondary consequences of air-conditioning dependence, systemic dehydration, and ultraviolet exposure. This narrative review synthesizes current evidence on the epidemiology, pathophysiological mechanisms, and management strategies pertaining to DED in the context of hot climatic environments and aims to inform both specialist and generalist clinicians managing affected patients. A structured literature search was conducted across PubMed, Google Scholar, and Scopus using terms including “dry eye disease,” “hot climate,” “temperature,” “humidity,” “tear evaporation,” and “ocular surface.” Peer-reviewed original articles, systematic reviews, and clinical guidelines published from 2000 to 2025 were appraised. Elevated ambient temperature is consistently associated with higher rates of DED diagnosis and tear film instability. Low RH accelerates tear evaporation and reduces tear breakup time. Air-conditioning—universally adopted in hot regions—paradoxically exacerbates ocular surface dryness by further reducing indoor humidity. Systemic dehydration, ultraviolet radiation, outdoor wind exposure, and air pollution synergistically worsen DED in hot-climate populations. Management must be multimodal, targeting both environmental modification and conventional therapeutic strategies. Hot climate is an underrecognized but clinically important driver of DED. Clinicians, public health authorities, and patients in affected regions must adopt evidence-based strategies to reduce the ocular surface burden attributable to climatic and environmental exposures.