Objective:

To analyze the association between extreme heat and acute-care presentations for various medical conditions among adults in the Chicago area.

Approach:

• Study Design: The study analyzed 916,904 emergency department and urgent care encounters among 372,140 adults from May to September between 2011 to 2023, using a 2-stage analytic framework.
• Data Analysis: Stage 1 involved diagnosis-specific quasi-Poisson models to identify relevant diagnoses, while Stage 2 used distributed lag nonlinear models to evaluate associations with temperature.

Key Findings:

• Extreme heat (≥33.67 °C) was linked to increased acute-care visits for renal and fluid-balance disorders, dermatologic conditions, multiple sclerosis, cannabinoid-related disorders, and a range of injury-related diagnoses.
• 33 diagnoses met reporting criteria, including significant associations for glomerular disorders, edema, acute kidney failure, and multiple sclerosis.
• Among injuries, the highest cumulative estimates were for assault, accidental firearm discharge, and lower-limb burns.

Interpretation:

Renal and fluid-balance disorders were notably affected by extreme heat, consistent with prior evidence of dehydration and renal stress.

Limitations:

• The study was limited to adults in 4 Chicago health care systems, affecting generalizability.
• The cohort overrepresented Black and West Side patients and underrepresented White and Northwest Side patients.
• Residential temperature may not reflect actual heat exposure experienced by patients.
• Socioeconomic variables were not included, leading to potential residual confounding.
• The study lacked external validation as both analytic stages used the same cohort.

Conclusion:

The findings indicate an association between extreme heat and acute care presentations, particularly for renal and injury-related conditions.

Sources:

• Science Advances