Extreme rainfall events are associated with an increased risk of death from all causes as well as from heart and lung diseases, finds an analysis of data from 34 countries and regions published by The BMJ . The health effects of extreme rainfall varied by local climate and vegetation coverage, providing a global perspective on the effect of extreme rainfall events on health. Climate change is intensifying the frequency and severity of short term rainfall events, and emerging evidence suggests a compelling link between rainfall events and adverse health outcomes, particularly transmission of infectious diseases.
But the influence of rainfall events on cardiovascular and respiratory health, and how varying rainfall intensities affect these conditions, remains understudied. To address this, researchers set out to examine the associations between daily rainfall (intensity, duration, and frequency) and all-cause, cardiovascular, and respiratory deaths. They analyzed daily mortality records and rainfall data from 645 locations across 34 countries or regions on six continents, comprising a total of 109,954,744 all-cause, 31,164,161 cardiovascular, and 11,817,278 respiratory deaths from 1980 to 2020.
The main measure of interest was the association between daily deaths and rainfall events with return periods (expected intervals between events) of one year, two years, and five years. Factors that might affect this association, such as local climate type, rainfall variability, and vege.