Sick leave among healthcare workers (HCWs) can disrupt hospital operations and negatively affect patient care quality. This study aimed to explore the factors associated with absenteeism due to sickness among HCWs in a tertiary hospital in Lebanon. A retrospective review of sick leave records and corresponding health data was conducted for 2,850 HCWs from 2015 to 2018. Sick leave events were classified by diagnostic categories. Associations between demographic, occupational, and health-related factors and sick leave frequency were evaluated using bivariate analysis and negative binomial regression models. Over the study period, employees experienced an average of 10.6 sick leave episodes. The most pronounced predictor of increased absenteeism was employment in lower-grade positions (IR = 1.52; 95% CI = 1.39–1.67). Additional significant predictors included being female (IR = 1.24; 95% CI = 1.14–1.36), older age (IR = 1.19; 95% CI = 1.08–1.30), marital status as married (IR = 1.21; 95% CI = 1.11–1.33), current smoking (IR = 1.21; 95% CI = 1.11–1.32), and presence of selected medical conditions. Sick leave occurrence among HCWs is shaped by a combination of personal, job-related, and health factors. Future investigations should assess how socio-economic disparities influence health outcomes and guide tailored interventions to support the well-being of essential healthcare personnel.
