Post-Intensive Care Syndrome (PICS) in adult survivors: A systematic review and meta-analysis of assessment tools, risk factors and long-term outcomes

<title>Abstract</title> <p>Post-Intensive Care Syndrome (PICS) encompasses persistent cognitive, psychological, and physical impairments affecting ICU survivors. Because of increasing survival rates, understanding long-term sequelae has become critical. We systematically reviewed the literature and synthesized evidence for PICS assessment, prevention, and outcomes. Our objectives are to analyze the current situation by focusing on assessment tools, while evaluating prevention strategies, identifying risk factors, exploring long-term outcomes, plus promoting awareness and best practices among healthcare professionals. A systematic review was performed across PubMed, Web of Science, Scopus, and CINAHL for publications from 2015–2025. Eligible studies were cohort designs involving adults aged ≥ 19 years with post-ICU outcomes assessed via validated instruments. Systematic reviews, meta-analyses, and pediatric studies were excluded. Methodological quality was evaluated using the STROBE checklist. For outcome domains reported by ≥ 3 cohorts with continuous data, random-effects meta-analysis was conducted using the DerSimonian–Laird estimator. Of 325 initial records, 22 cohort studies met inclusion criteria (N = 8,487 participants; 45% COVID-19). PICS incidence ranged from 30% to 90%, with cognitive deficits up to 66%, psychological symptoms in &gt; 60%, and physical impairments in nearly 50% of ICU survivors. Random-effects pooled estimates identified significant functional impairment: 6-minute walk test 406 m (95% CI 396–417; I² = 0%), EQ-5D index 0.79 (0.70–0.87; I² = 93%), HADS-anxiety 4.7 (3.9–5.5; I² = 82%), HADS-depression 4.9 (3.7–6.1; I² = 90%). Risk factors included prolonged mechanical ventilation, deep sedation, delirium, and advanced age. As preventive strategies, the ABCDEF bundle and early mobilization significantly reduced PICS incidence. Assessment tools included MoCA, HADS, and Barthel Index. High heterogeneity across instruments underscores the absence of standardised measurement frameworks. PICS constitutes a multifaceted and highly prevalent condition associated with persistent, long-term sequelae. Standardized protocols for prevention, assessment, and rehabilitation are essential to optimize long-term outcomes and facilitate patient recovery. Systematic Review Registration (PROSPERO CRD420251169220).</p>