Geospatial Variability in Excess Death Rates during the COVID-19 Pandemic in Mexico: Examining Socio Demographic and Population Health Characteristics

Background

Mexico has suffered one of the highest COVID-19 mortality rates in the world. In this study we examined how socio demographic and population health characteristics shape the geospatial variability in excess mortality patterns during the COVID-19 pandemic in Mexico.

Methods

Weekly all-cause mortality time series for all 32 Mexican states, from January 4, 2015 to April 10, 2021, were analyzed to estimate the excess mortality rates using Serfling regression models. The association between socio-demographic, health indicators and excess mortality rates were determined using multiple linear regression analyses. Finally, we used functional data analysis to characterize clusters of states with distinct mortality growth rate curves.

Results

The overall all-cause excess deaths rate during the COVID-19 pandemic in Mexico until April 10, 2021 was estimated at 39.66 per 10 000 population. The lowest excess death rates were observed in southeastern states including Chiapas (12.72), Oaxaca (13.42) and Quintana Roo (19.41) whereas Mexico City had the highest excess death rate (106.17), followed by Tlaxcala (51.99) and Morelos (45.90). We found a positive association of excess mortality rates with aging index (P value<.0001), marginalization index (P value<.0001), and average household size (P value=0.0003) in the final adjusted model (Model R ² =76%). We identified four distinct clusters with qualitatively similar excess mortality curves.

Conclusion

Central states exhibited the highest excess mortality rates whereas the distribution of aging index, marginalization index, and average household size explained the variability in excess mortality rates across Mexico. Our findings can help tailor interventions to mitigate the mortality impact of the pandemic.

Key message

• This study quantified and examined spatial patterns of excess mortality across states of Mexico, with lower rates of excess mortality in southeastern states and higher rates in central states.

• Mexico City recorded 1 in 5 of all excess deaths in reported in Mexico, which accounted for 19% of total excess deaths across the country.

• Findinds indicate that aging index, marginalization index, and average household size played a significant role on excess death rates across Mexican states during the COVID-19 pandemic.

• Four distinct clusters characterized the excess mortality curves across Mexican states.