For a study, researchers sought to assess the relationship between county-level tropical storm exposure and death rates from various causes in the United States. A retrospective observational research utilizing a Bayesian conditional quasi-Poisson model to investigate the relationship between tropical cyclones and monthly death rates. Over a 31-year period (1988-2018), data from 33.6 million fatalities in the United States were obtained from the National Center for Health Statistics, covering inhabitants of the 1,206 counties in the United States that suffered at least one tropical cyclone during the research period. Tropical cyclone days per county-month are the number of days in a month with sustained maximum wind speeds of 34 knots or higher. Monthly county-level mortality rates by 6 underlying causes of death: malignancies, cardiovascular illnesses, infectious and parasitic diseases, injuries, neuropsychiatric problems, and respiratory diseases. The model produced data on the relationship between each additional cyclone day per month and monthly county-level mortality compared to the same county-month in previous years, up to 6 months after tropical cyclones, and how these estimated associations varied by age, gender, and social vulnerability. County-month was the unit of analysis.

The 6 causes listed in 1,206 US counties resulted in 33,619,393 deaths (16,691,681 females and 16,927,712 males; 8,587,033 aged 0-64 years and 25,032,360 aged 65 years or more). In all, the listed US counties had a median of two tropical cyclone days. Each additional cyclone day was associated with increased death rates for injuries (3.7% [95%CrI, 2.5%-4.9%]; 2.0 [95% CrI, 1.3-2.7] additional deaths per 1,000,000 for 2018 monthly age-standardized median rate [DPM]; 54.3 to 56.3 DPM), infectious and parasitic diseases (1.8% [95% CrI, 0.1% -3.6%]; 0.2 [95% CrI, 0.0-0.4] additional DPM; 11.7 to 11.9 DPM), respiratory diseases (1.3% [95% CrI, 0.2%-2.4%]; 0.6 [95% CrI, 0.1-1.1] additional DPM; 44.9 to 45.5 DPM), cardiovascular diseases (1.2% [95% CrI, 0.6%-1.7%]; 1.5 [95% CrI, 0.8-2.2] additional DPM; 129.6 to 131.1 DPM), neuropsychiatric conditions (1.2% [95% CrI, 0.1%-2.4%]; 0.6 [95% CrI, 0.1-1.2] additional DPM; 11.7 to 11.9 DPM), respiratory diseases (1.3% [95% CrI, 0.2% -2.4%]; 0.6 [95% CrI, 0.1-1.1] additional DPM; 44.9 to 45.5 DPM), cardiovascular diseases (1.2% [95% CrI, 0.6% -1.7%]; 1.5 [95% CrI, 0.8-2.2] additional DPM; 129.6 to 131.1 DPM), neuropsychiatric conditions (1.2% [95% CrI, 0.1%-2.4%]; 0.6 [95% CrI, 0.1-1.2] additional DPM; 52.1 to 52.7 DPM), with no change for cancers (−0.3% [95% CrI, −0.9% to 0.3%]; −0.3 [95% CrI, −0.9 to 0.3] additional DPM; 100.4 to 100.1 DPM).

From 1988 to 2018, each additional cyclone day per month was associated with slightly higher death rates in the months following the cyclone for several causes of death, including injuries, infectious and parasitic diseases, cardiovascular diseases, neuropsychiatric conditions, and respiratory diseases in the US counties that experienced at least one tropical cyclone.

Reference:jamanetwork.com/journals/jama/article-abstract/2789661