Drought associated with risk of hospital admissions and mortality
In a new study, NIEHS grantees reported an association between drought conditions and increased risk of death among older adults. The researchers also observed a decreased risk of respiratory-related hospital admissions during periods of full drought. According to the authors, the work was the first to systematically analyze the risk of hospital admissions and mortality associated with drought periods in the U.S.
By analyzing 2000 to 2013 drought maps for 618 counties in the western U.S., the researchers identified periods of full droughts, nondrought, and worsening drought. They classified the days when droughts worsened as high- and low-severity droughts. Using Medicare records from the same period, the team calculated daily rates of hospital admissions and deaths among people aged 65 years old or older that were related to cardiovascular or respiratory causes.
The study showed that compared with nondrought periods, respiratory admissions decreased by a small but statistically significant amount during the full drought period but not during worsening drought conditions. The risk of dying was increased by a small but statistically significant amount during high-severity worsening drought periods but not during full drought or low-severity worsening droughts. Overall, cardiovascular-related hospital admissions did not differ significantly during either full drought or worsening drought periods. However, counties where drought occurred less frequently showed an increased risk for cardiovascular disease and death during worsening drought conditions.
In the same issue, a comment by NIEHS Senior Advisor for Public Health John Balbus, M.D., noted that the groundbreaking study helped identify future research questions about how drought affects health, and the actual severity and significance of those effects.
Citation: Berman JD, Ebisu K, Peng RD, Dominici F, Bell ML. 2017. Drought and the risk of hospital admissions and mortality in older adults in western USA from 2000 to 2013: a retrospective study. Lancet Planet Health 1(1):e17–e25.