Sociodemographic and Clinical Determinants of Repeated Blood Donation in Luanda, Angola

Background: Repeat blood donation is essential for ensuring a safe and sustainable blood supply, particularly in sub-Saharan Africa, where donation rates remain below WHO targets. Herein, we investigated the sociodemographic and clinical determinants associated with repeated blood donation among blood donors’ candidates in Luanda, the capital city of Angola. Materials and Methods: A cross-sectional study was conducted among 189 blood donors between June 2025 and February 2026. The outcome of interest was repeat blood donation, defined as more than two previous donations. Sociodemographic and clinical characteristics were collected, and multivariate logistic regression analysis was performed to identify factors independently associated with repeated donation. Results: Of the 189 participants, 14 (7.4%) had donated blood more than twice, with a median age of 34.5 years (IQR: 27.3–37.8). Male gender was independently associated with repeated blood donation [AOR: 5.81 (95% CI: 1.14–29.6), p=0.034]. Although not statistically significant, higher odds of repeat donation were also observed among donors aged ≥ 30 years (AOR: 2.83, p = 0.127), residents outside Luanda city (AOR: 1.22, p = 0.753), employed individuals (AOR: 2.05, p = 0.319), voluntary donors (AOR: 2.08, p = 0.326), and anaemic donors (AOR: 3.36, p = 0.106). Conclusions: Male gender was an independent determinant of repeated blood donation in this study. The higher frequency of repeated donation among anaemic donors highlights the need for further research on iron depletion and for improved donor monitoring strategies to ensure a safe and sustainable blood supply in Angola.