Post-Infectious Fatigue and Depression Following Dengue: A Systematic Review and Meta-Analysis of Associated Factors.

Post-dengue fatigue syndrome is a debilitating long-term condition that affects daily activities, quality of life, and productivity. Its underlying mechanisms remain unclear, but clinical similarities with post-dengue depression complicate differentiation. Therefore, we conducted a systematic review and meta-analysis to identify and compare factors associated with post-dengue fatigue and post-dengue depression. We searched PubMed, Science Direct, Web of Science and Google Scholar databases until 6 June 2025, with an update performed on 31 December 2025. This systematic review was conducted according to PRISMA guidelines. Meta-analyses were conducted to assess associations of demographic, biological, clinical, medical or psychosocial factors with post-dengue fatigue and post-dengue depression using pooled odds ratios (OR). The study protocol was registered in PROSPERO (CRD420250655004). Nine studies (2006-2023) covering 1470 patients were included. The systematic review identified 13 factors eligible for meta-analysis: twelve factors for post-dengue fatigue and one for post-dengue depression. Among these factors, female sex (OR 1.69, 95% CI: 1.33-2.14), myalgia (OR 3.45, 95% CI: 2.10-5.69), and severe dengue (OR 4.02, 95% CI: 1.45-11.13), particularly dengue haemorrhagic fever (OR 1.53, 95% CI: 1.04-2.24), were associated with post-dengue fatigue. No factor was associated with post-dengue depression in the meta-analysis. However, narrative synthesis revealed thrombocytopaenia as a shared factor of both outcomes. This study highlights risk profiles for post-dengue fatigue syndrome and depression, with female sex, myalgia, and dengue severity specifically associated with fatigue, while thrombocytopaenia might indicate a shared pathway. These findings support targeted surveillance and management strategies for at-risk patients and highlight the need for further research into post-dengue depression mechanisms.