Morbidity and mortality of COVID-19 negatively associated with the frequency of consanguineous marriages, an ecologic study

Background: Union between second cousins and closer relatives is called consanguineous marriage. Consanguineous marriage is associated with increased risk of autosomal recessive diseases and several multifactorial traits. In order to evaluate the association between prevalence/mortality of COVID-19 and the frequency of consanguineous marriage, the present ecologic study was carried out. For the present study, data of prevalence (per 10(6) people) and mortality (per 10(6) people) and number of performed laboratory diagnostic test (per 10(6) people) of COVID-19 disease at four time points (December 2020; March, August and October 2021) of 65 countries were used. Results: Univariable correlation and generalized estimating equation analysis were used. In analysis, prevalence and mortality of COVID-19 were used as dependent variables and human development index, number of performed diagnosis test and the mean of inbreeding coefficient (alpha-value) were introduced into model as covariates, and time point was used as a factor in analysis. The square root (SR) of prevalence (P = 0.008) and SR-mortality (P < 0.001) of COVID-19 negatively associated with the log-transformed of alpha-value. Conclusions: The present finding means that in countries with high levels of consanguineous marriages, the prevalence of COVID-19 and mortality due to COVID-19 were lower than countries having low level of marriage with relatives.