The impact of socio-economic status on infant deaths: a case-control study from Istanbul

Abstract Background Socioeconomic disparities continue to impact child health. This study aimed to determine the association between socioeconomic status (SES) and infant mortality (IM) in a district in Istanbul. Methods This is a case-control study conducted in a district of Istanbul. The cases were all infants born alive who died before reaching the age of one between January 1, 2021, and December 31, 2022. The controls were randomly selected children who were born and survived their first year. The sample size was calculated as 83 cases and 166 controls assuming low SES doubled IM, with 80% power and an alpha error of 0.05. Data were obtained through health records and telephone interviews. SES was evaluated through a validated index that used parents’ education and occupation, households’ vehicles and ownership of electrical devices, house ownership, and the land value of the living area. SES was categorized into three groups: low, middle, and high. Logistic regression was used in the analysis. Results The response rate was 51.8%, with 42 cases and 87 controls. The multivariate model included mothers’ age, smoking status, presence of maternal chronic diseases and anemia, multiple gestations, antenatal visits (≥4 vs.