Non-communicable diseases (NCDs) contribute significantly to the global health burden, and their outcomes may be influenced by temperature variations. This study evaluated the impact of ambient temperature on emergency department (ED) visits and associated mortality of certain NCDs in a low-resource tertiary care setting in Pakistan.

An electronic health records (EHR) review was conducted for adults (≥18 years) presenting to Indus Hospital and Health Network (IHHN) ED (Karachi, Pakistan) from 2014 to 2024. Patients with hypertension (HTN), diabetes mellitus (DM), ischemic heart disease (IHD), obstructive lung disease (OLD), chronic kidney disease (CKD), or cerebrovascular accident (CVA) were included. Daily ambient temperatures were sourced from OpenWeather. Visit and mortality rates were stratified across temperature categories. Temperature effects on mortality risk were modeled using the Accelerated Failure Time (AFT) model. Autoregressive Distributed Lag (ARDL) models evaluated the delayed effect of extreme heat (≥31 °C) on daily mortality rates.

Of the 1003,894 adult ED patients, NCD visits varied from 6–60/day at various temperatures with visits decreasing with rising ambient temperatures. Mortality rates rose at temperature extremes (<20 °C and ≥31 °C). Time to death or discharge decreased by 14–25% in higher temperatures (≥31 °C) when compared with temperatures between 25.5–29.5 °C for HTN, DM, IHD, and CVA, as confirmed through the AFT model. ARDL models confirmed a delayed effect of extreme temperature (≥31 °C) on mortality rates for HTN, IHD, and CVA.

Temperature extremes were found to significantly influence NCD-related ED burden and outcome. The findings from the study highlight the need for climate-adaptive emergency care strategies in low-resource settings.