Overcrowded Housing Increases Risk for COVID‐19 Mortality: An Ecological Study

RESEARCH OBJECTIVE: COVID‐19 has devastated the United States (US) population and exacerbated existing health inequalities. Those residing in areas of high population density are at an elevated risk, suggesting that residence in an overcrowded household may result in heightened vulnerability. However, as the association between residing in an overcrowded household and risk of mortality from COVID‐19 is unknown, the purpose of this study was to analyze this relationship. STUDY DESIGN: COVID‐19 data for Los Angeles County was acquired, along with data on housing and demographics. Overcrowded households were defined as having 1.0+ persons per room. Bivariate regression was then performed, followed by backwards stepwise linear regression. This included overcrowded housing as a predictor variable and COVID‐19 death totals as an outcome variable. Collinearity was assessed via the variance inflation factors (VIF); variables were removed if they had a VIF >8. POPULATION STUDIED: Population‐level data was retrieved for each of the 85 cities in Los Angeles county, the region with the highest number of COVID‐19 cases in the US. Data for this population came from the Los Angeles County Government, as well as the US Census Bureau. PRINCIPAL FINDINGS: Bivariate regression indicated that the number of overcrowded households was positively associated with total COVID‐19 deaths (standardized β = 0.844, p < 0.001). COVID‐19 case totals, number of individuals aged 60 or above, and number of overcrowded households met conditions for inclusion in the backwards stepwise linear regression model. This analysis revealed all independent variables were positively associated with number of deaths, with the largest effect being seen with overcrowded housing (standardized β(1) = 0.386, p = 0.001), followed by number of cases (standardized β(2) = 0.307, p = 0.014), and number of individuals aged 60+ (standardized β(3) = 0.282, p < 0.001). CONCLUSIONS: Overcrowded housing was found to be a major risk factor for COVID‐19 mortality and served as a better predictor of number of deaths in a city than the number of people 60+, and even the total number of COVID‐19 cases. IMPLICATIONS FOR POLICY OR PRACTICE: These findings have important implications for addressing the COVID‐19 pandemic. While age and comorbidities have frequently been described as risk factors for poor outcomes, these findings indicate a critical need for COVID‐19 control efforts to more thoroughly assess for overcrowded housing. The striking absence of research and data collection on overcrowded housing indicates a clear direction for future studies.