Impact of the COVID-19 pandemic on temporal patterns of mental health and substance abuse related mortality in Michigan: An interrupted time series analysis.

Background: The emergence of SARS-CoV2 (COVID-19) had wide impacts to health and mortality and prompted unprecedented containment efforts. The full impact of the COVID-19 pandemic and resulting responses on mental health and substance abuse related mortality are unknown. Methods: We obtained records for deaths from suicide, alcohol related liver failure, and overdose from the Michigan Department of Health and Human Services (MDHHS) for 2006 to 2020. We compared mortality within sex, age, marital, racial and urban/rural groups using basic statistical methods. We compared standardized mean daily mortality incidence before and after the onset of the pandemic using t-tests. We used an interrupted time series approach, using generalized additive Poisson regression models with smoothed components for time to assess differences in mortality trends before and after the onset of the pandemic within demographic groups. Findings: There were 19,365 suicides, 8,790 deaths from alcohol related liver failure, and 21,778 fatal drug overdoses. Compared with 2019, suicides in 2020 declined by 17.6%, overdose mortality declined by 22.5%-while alcohol deaths increased by 12.4%. Crude comparisons suggested that there were significant declines in suicides for white people, people 18 to 65 and increases for rural decedents, overdoses increased for Black people, females and married/widowed people, and alcohol mortality increased for nearly all groups. ITS models, however, suggested increased suicide mortality for rural residents, significantly increased alcohol related mortality for people ≥65 and increased overdose mortality in men. Interpretation: The onset of the pandemic was associated with mixed patterns of mortality between suicide, alcohol and overdose deaths. Patterns varied within demographic groups, suggesting that impacts varied among different groups, particularly racial and marital groups. Funding: This work was supported by the United States National Institute of Environmental Health Sciences [K99/R00ES026198] and their Michigan Center on Lifestage Environmental Exposures and Disease [grant number P30ES017885]; and the Institute for Global Biological Change at the University of Michigan.