To estimate the long-run mortality effects of Hurricanes Katrina and Rita on seniors with diabetes.
We performed a retrospective cohort analysis of Medicare enrollment and claims data covering four states and ~10 years. Affected individuals were identified by whether they lived in a county that suffered a high impact and were stratified by whether they moved to a different county following the storms. Propensity scores matched affected and comparison subjects based on demographic and socioeconomic characteristics and the presence of chronic conditions. Our sample consisted of 170,328 matched affected subjects.
The affected subjects had a nearly 40% higher all-cause mortality risk in the 1st month after the storms, but the difference fell to <6% by the end of the full observation period. The mortality risks of heart disease and nephritis also exhibited the largest differences immediately following the storms. Among the affected subjects, the all-cause mortality risk was higher for those who moved to a different county, with an especially large difference among those who moved to an affected county.
The propensity matching procedure resulted in the comparison and affected groups having similar observable characteristics. However, we only examined the extreme outcome of mortality, our definition of affected was somewhat crude, and our sample did not include individuals enrolled in Medicare Advantage. Our findings highlight the importance of the immediate response to disasters, yet also demonstrate the long-lasting impact disasters can have.