The impact of COVID-19 on deaths from dementia and Alzheimer's disease in Chile: an analysis of panel data for 16 regions, 2017-2022

Background: Although several studies have documented the detrimental impacts of global COVID-19 containment measures on individuals with Alzheimer's disease and dementia, a comprehensive analysis of mortality rates for these conditions within the Chilean population is notably lacking. This study aimed to analyze the impact of COVID-19 on mortality rates among individuals with dementia and Alzheimer's disease in Chile.

Methods: A retrospective longitudinal cross-sectional study was conducted, considering mortality data for specific mental health conditions during the pre-pandemic and pandemic contexts of COVID-19 in Chile. Quantile regression techniques were employed to analyze the existence of differences between the two periods, while non-observable heterogeneity models for panel data methods were used to evaluate the effect of COVID-19 mortality on crude mortality rates.

Findings: Statistically significant differences were observed in the number of deaths from dementia and Alzheimer's disease between the pre-pandemic and COVID-19 pandemic periods. Specifically, crude mortality rates decreased by 10% (-0.10 [95% CI: -0.16, -0.05]) during the pandemic period. Furthermore, the number of deaths from COVID-19 during the pandemic period has a very weak incidence of deaths from mental health conditions such as dementia and Alzheimer's. Specifically, a unit percentage increase in confirmed cases from COVID-19 would result in a 7% (-0.07 [95% CI: -0.13, -0.001]) decrease in the number of deaths from dementia and Alzheimer's. These findings are supported by the application of panel regression with one-way random effects models.

Interpretation: The study findings indicate a reduction in mortality rates attributed to dementia and Alzheimer's disease during the COVID-19 pandemic in Chile. This decline could be attributed to the potential underreporting of mental illness as the cause of death during the pandemic period. Several studies have highlighted that approximately 30% of death certificates fail to document the presence of a dementia syndrome. Moreover, the cause of death recorded for individuals with mental health conditions may be influenced by the physician's familiarity with the patient or reflect the prevailing approach to managing end-stage dementia patients.

Funding: This work received no funding.