The impact of the COVID-19 pandemic on all-cause mortality and life expectancy in northern Ghana: findings from the Navrongo Health and Demographic Surveillance System.

BACKGROUND

Measurement of excess mortality attributable to the COVID-19 pandemic is essential for quantifying the direct and indirect effects on mortality and informing future public health control strategies. This study assessed the impact of COVID-19 on excess mortality and life expectancy at birth in rural northern Ghana.

METHODS

Data was obtained from the Navrongo Health and Demographic Surveillance System (NHDSS) in Ghana. We computed the number of deaths and person-years contributed from January 1, 2015, to December 31, 2021, and estimated mortality rates for each year, age group, and gender. Mortality rate differences were calculated by comparing the period before (2018-2019) and during (2020-2021) the pandemic. To estimate excess mortality, a generalised additive model was fitted to the historical data from 2015 to 2019 to predict the expected mortality rates in the COVID-19 period (2020-2021). A Cox proportional hazards model was fitted to assess the risk factors associated with mortality, adjusting for socio-demographic variables. Conventional life table techniques were used to estimate period life expectancy at birth for males and females.

RESULTS

Overall, 12,413 deaths and 1,227,115 person-years were included in the analysis. This consists of 5,930 (49%) deaths and 572,963 person-years for the pre-pandemic period (2015-2019) and 6,483 (52%) deaths and 654,153 person-years for the pandemic period (2020-2021). From 2020 to 2021, the crude mortality rate was 23.9 deaths per 1000 person-years compared with 20.7 deaths per 1000 person-years predicted if COVID-19 had not occurred. COVID-19 also caused a decline in life expectancy at birth, especially in males, by 3.4 years. In addition, the adjusted risk of dying during the pandemic was higher in males (12.1%) compared to females and higher in the 65 + years age group (69.2%) compared to the younger population.

CONCLUSION

The COVID-19 pandemic caused an increase in deaths and a decrease in life expectancy in the NHDSS population in Ghana, particularly among men and those aged 65 years and older. These results reinforce the critical role of routine surveillance data in assessing the impact of public health emergencies such as the COVID-19 pandemic and informing public health strategies.