What can multiple causes of death tell about cardiovascular mortality during COVID-19 pandemic in the United States?

BACKGROUND: The COVID-19 pandemic may have caused an underestimation of cardiovascular disease (CVD) mortality, as COVID-19 was predominantly recorded as the underlying cause of death. This study investigates CVD-related excess mortality and recording of CVD on the death certificates during 2020-2021, considering underlying (underlying causes of death (UCD)), immediate and contributory causes. METHODS: We utilize US Multiple-Cause-of-Death Mortality Data. Excess deaths are assessed by comparing actual 2020-2021 deaths with Seasonal Autoregressive Integrated Moving Average model predictions. To understand changes in cause-of-death recording, we use the standardized ratio of multiple to underlying causes (SRMU). RESULTS: Excess CVD mortality is most prominent in contributory causes, including hypertensive disease, essential hypertension, and acute myocardial infarction. While excess of contributory CVDs generally decreased in 2021, acute myocardial infarction, pulmonary heart diseases and other circulatory diseases showed a continual increase. Changes in SRMU from 2020 to 2021, compared to 2010-2019, reveal shifts in coding practices, particularly for pulmonary heart, cerebrovascular diseases, non-rheumatic valve disorders and heart failure. CONCLUSIONS: The COVID-19 pandemic has significantly increased CVD-related mortality, which is not fully captured in conventional analyses based solely on the UCD. The trend of coding CVDs as non-underlying causes of death accelerated during 2020-2021. Multiple-causes-of-death should be employed to evaluate mortality when new leading cause of death emerges.

Racial/Ethnic disparities in the chains of morbid events leading to death: network analysis of US multiple cause of death data.

Multiple-cause-of-death data have not yet been applied to the study of racial/ethnic differences in causal chains of events leading to death, nor they have been used to examine racial/ethnic disparities in cause-of-death certification. We use publicly available 2019 US death certificate data to reassemble chains of morbid events leading to death. From them, we construct and analyze directed multiple cause of death networks by race and sex of deaths aged 60+. Three perspectives to measure disparities are employed: (i) relative prevalence of cause-of-death-pairs, (ii) strength of associations between diseases, (iii) similarities in transition matrices. Non-Hispanic Blacks (NHB) had overall lower prevalence of cause of death pairs, Hispanics (HIS) were burdened more by alcohol-related mortality and Asian and Pacific Islanders (API) exceeded in transitions to cerebrovascular diseases. Lower similarity was observed in transitions to external causes of death, dementia and Alzheimer's disease, pulmonary heart diseases, interstitial respiratory diseases, and diseases of the liver. After excluding rare diseases, the similarity further decreased for ill-defined conditions, diabetes mellitus, other cardiovascular diseases, diseases of the pleura, and anemia. To sum up, races/ethnicities not only vary in structure and timing of death but they differ in morbid processes leading to death as well.