# Variation in One‐Year Mortality Following Severe Weather Exposure Among Older Americans by Chronic Health Condition and Sociodemographic Status

## TL;DR

Exposure to severe weather like Hurricane Harvey increases one-year mortality among older Americans, especially those with chronic health conditions and minority groups.

## Contribution

This study identifies long-term mortality disparities following severe weather exposure among vulnerable older adults, including those with chronic health conditions and minority populations.

## Key findings

- High rain exposure was associated with a 3% higher mortality risk in the year following Hurricane Harvey.
- Older adults with Alzheimer's disease and related dementias, diabetes, and chronic kidney disease had higher mortality risks after high rain exposure.
- Non-Hispanic Black and Hispanic/Latino populations experienced significantly higher mortality risks following severe weather exposure.

## Abstract

While the immediate effect of exposure to severe weather from hurricanes on mortality is well documented, it is unknown whether mortality in the year following exposure to severe weather differs across older Americans with specific vulnerable characteristics. This paper sought to determine whether the association between exposure to high rain and one‐year mortality differs across vulnerable subgroups of older adults.

This retrospective cohort study used Medicare claims data from fee‐for‐service beneficiaries aged ≥ 65 in Texas and Louisiana in the year before and after Hurricane Harvey. Historical weather data was used to construct a 4‐day measure of cumulative rainfall, the primary severe weather caused by Hurricane Harvey. We identified vulnerable subgroups based on five chronic health conditions requiring regular healthcare access, and sociodemographic factors (e.g., ≥ 85 years, dual eligibility). Cox proportional hazards regression was used to adjust for covariates when estimating the association between high rain exposure and mortality up to 1 year after exposure.

In adjusted models, high rain exposure was significantly associated with greater mortality risk (HR 1.03, 95% CI 1.01–1.05). Among those with chronic health conditions including Alzheimer's disease and related dementias (ADRD) (HR 1.05 [95% CI 1.03, 1.08]), diabetes (HR 1.04 [1.02, 1.07]), and chronic kidney disease (HR 1.04 [1.01, 1.06]) exposed to high rain versus those unexposed to high rain, associations with high rain were found. Higher mortality was also observed among Non‐Hispanic Black (HR 1.06 [95% CI 1.01, 1.11]) and Hispanic and Latino populations (HR 1.13 [95% CI 1.08, 1.19]).

Exposure to high rain from Hurricane Harvey was associated with higher one‐year mortality that varied across vulnerable groups. The largest associations were observed among older adults with health conditions that require regular healthcare (e.g., CKD, ADRD) and minoritized racial and ethnic groups.

Key points
○Exposure to high rainfall during Hurricane Harvey was associated with increased one‐year mortality among older adults.○Mortality risk was highest among those with chronic health conditions requiring regular care, including chronic kidney disease and Alzheimer's disease and related dementias.○Non‐Hispanic Black and Hispanic/Latino populations experienced higher mortality risks, highlighting disparities in disaster vulnerability.
Why does this paper matter?
○This study provides new evidence that severe weather events have long‐term health consequences for vulnerable older adults. Identifying populations at heightened risk for disasters can inform targeted preparedness and healthcare interventions to reduce mortality disparities.

Key points
○Exposure to high rainfall during Hurricane Harvey was associated with increased one‐year mortality among older adults.○Mortality risk was highest among those with chronic health conditions requiring regular care, including chronic kidney disease and Alzheimer's disease and related dementias.○Non‐Hispanic Black and Hispanic/Latino populations experienced higher mortality risks, highlighting disparities in disaster vulnerability.

Exposure to high rainfall during Hurricane Harvey was associated with increased one‐year mortality among older adults.

Mortality risk was highest among those with chronic health conditions requiring regular care, including chronic kidney disease and Alzheimer's disease and related dementias.

Non‐Hispanic Black and Hispanic/Latino populations experienced higher mortality risks, highlighting disparities in disaster vulnerability.

Why does this paper matter?
○This study provides new evidence that severe weather events have long‐term health consequences for vulnerable older adults. Identifying populations at heightened risk for disasters can inform targeted preparedness and healthcare interventions to reduce mortality disparities.

This study provides new evidence that severe weather events have long‐term health consequences for vulnerable older adults. Identifying populations at heightened risk for disasters can inform targeted preparedness and healthcare interventions to reduce mortality disparities.