Factors influencing long-term health-related quality of life among intensive care unit survivors: a mixed-methods systematic review.

Objective: To comprehensively synthesize the objective clinical determinants and subjective experiences shaping long-term health-related quality of life (HRQOL) among Intensive Care Unit (ICU) survivors. Methods: Seven databases were searched through May 1, 2026. Eligible studies examined HRQOL and its determinants in adult ICU survivors. Outcomes assessed at ≥3 months after discharge were used for the primary long-term interpretation, whereas assessments before 3 months were retained as early-recovery evidence. Two reviewers independently screened studies, extracted data, and appraised individual studies using the Mixed Methods Appraisal Tool (MMAT). Quantitative evidence was synthesized by effect direction and major determinant, HRQOL bodies of evidence were assessed using an adapted GRADE approach. Quantitative and qualitative evidence was synthesized separately and subsequently integrated using a convergent segregated approach. Results: Fifty-three eligible studies were included in the final synthesis. Long-term HRQOL was associated with pre-existing health status, acute illness severity, post-intensive care physical, psychological, and cognitive impairments, functional limitation, rehabilitation, and social support. Pre-ICU chronic disease, frailty, disability, and baseline HRQOL emerged as important contextual determinants and potential confounders of apparent ICU-related associations. Conclusions: Long-term HRQOL impairment is a multi-layered outcome of biomedical, symptomatic, functional, and environmental interactions. Post-ICU rehabilitation should transition toward multidisciplinary, continuous care that combines physical therapy with cognitive-psychological support and robust transitional care networks to foster successful societal reintegration. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/view/CRD420261398874, identifier: CRD420261398874.