Correlation between COVID 19 and selected risk factors: an ecological study

INTRODUCTION: The World Health Organization (WHO), on March 11, 2020, has declared the novel coronavirus (COVID-19) outbreak a global pandemic. COVID-19 originated from Wuhan; China spread to 218 Countries and Territories around the world. We planned this study to assess the correlation between COVID-19 and selected risk factors.
METHODS: An ecological study was conducted in December 2020. Data regarding the COVID-19 confirmed cases and deaths per million populations were retrieved using Our World in Data until 28th November 2020. Data regarding socio-demographic related factors of countries and health-related factors were also extracted from the same database. We have categorized countries according to Global Burden of Disease(GBD) super regions and World Bank income levels. We have applied Spearman's rank correlation coefficient to assess the correlation between COVID-19 cases and deaths with various socio-demographic and health-related factors.
RESULTS: In this study, highest number of COVID-19 confirmed cases and deaths were reported in World Bank high-income groups. Globally, we found significant positive correlations between COVID-19 deaths per million with various socio-demographic related and health related factors like median age (r=0.543,p<0.001), percentage of population aged ≥65 years (r=0.546,p<0.001), GDP per capita (r=0.531,p<0.001), HDI (r=0.567,p<0.001), female smoking (r=0.509,p<0.001), availability of hand-washing facilities (r=0.608,p<0.001), diabetes (r=0.166,p<0.05) and hospital beds per 1000 population (r=0.383,p<0.001), whereas extreme poverty is negatively correlated (r= -0.490,p<0.001).
DISCUSSION AND CONCLUSION: Extra emphasis on high-income countries is required to reduce the burden of COVID 19 cases and deaths. A multi-centric study should be planned to know the reasons for the high burden of cases and deaths in high-income countries.