The Perils of Heat Waves for Vulnerable Older Adults

TOPLINE:

Heat waves are associated with an increase in heat-related emergency department visits, hospitalizations, and deaths among dually eligible individuals older than 65 years.

METHODOLOGY:

• The researchers conducted a retrospective time-series study using national Medicare and Medicaid data from 2016 to 2019 to assess the link between heat waves during warm months and adverse health events.
• A total of 5,448,499 dually eligible individuals (66% women; 20% aged ≥ 85 years) were included from 28,404 zip code areas across 50 states and Washington, DC.
• Heat waves were defined as three or more consecutive days of extreme heat with a maximum temperature of at least 90 °F and within the 97th percentile of daily maximum temperatures for each zip code.
• Primary outcomes were daily counts of heat-related emergency department visits and hospitalizations.
• Secondary outcomes were all-cause and heat-specific emergency department visits, all-cause and heat-specific hospitalizations, deaths, and long-term nursing facility placements within 3 months after a heat wave.

TAKEAWAY:

• Heat waves were associated with a 10% increase in heat-related emergency department visits (incidence rate ratio [IRR], 1.10; 95% CI, 1.08-1.12) and a 7% increase in heat-related hospitalizations (IRR, 1.07; 95% CI, 1.04-1.09).
• Mortality rates were 4% higher during heat wave days than during non–heat wave days (IRR, 1.04; 95% CI, 1.01-1.07).
• No significant difference was found in rates of long-term nursing facility placements or heat-related emergency department visits for nursing facility residents.
• All racial and ethnic groups showed higher incidence rates of heat-related emergency department visits during heat waves, especially among beneficiaries identified as Asian (IRR, 1.21; 95% CI, 1.12-1.29). Rates were higher among individuals residing in the Northwest, Ohio Valley, and the West.

IN PRACTICE:

“In healthcare settings, clinicians should incorporate routine heat wave risk assessments into clinical practice, especially in regions more susceptible to extreme heat, for all dual-eligible beneficiaries and other at-risk patients,” wrote Jose F. Figueroa, MD, MPH, of the Harvard T.H. Chan School of Public Health in Boston, in an invited commentary. “Beyond offering preventive advice, clinicians can adjust medications that may increase their patients’ susceptibility during heat waves, or they can refer patients to social workers and social service organizations to ensure that they are protected at home.”

SOURCE:

This study was led by Hyunjee Kim, PhD, of the Center for Health Systems Effectiveness at Oregon Health & Science University in Portland, Oregon. It was published online on November 8, 2024, in JAMA Health Forum.

LIMITATIONS:

This study relied on a claims database to identify adverse events, which may have led to omissions in coding, particularly for heat-related conditions if the diagnostic codes for heat-related symptoms had not been adopted. This study did not adjust for variations in air quality or green space, which could have confounded the association of interest. Indoor heat exposures or adaptive behaviors, such as air conditioning use, were not considered. The analysis could not compare the association of heat waves with adverse events between those with dual eligibility and those without dual eligibility.

DISCLOSURES:

This study was supported by the National Institute on Aging. One author reported receiving grants from the National Institutes of Health outside the submitted work. No other disclosures were reported.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.