Biological and epigenetic pathways linking PTSD to accelerated aging: a systematic review and narrative synthesis

BACKGROUND: Post-traumatic stress disorder (PTSD) may accelerate biological aging, but the pathways and evidence remain uncertain. We systematically reviewed associations between PTSD and epigenetic and other aging biomarkers. METHODS: We searched PubMed, Embase, Web of Science, and Scopus through 1 March 2026 for studies of adults with validated PTSD assessment. Two reviewers screened records and extracted data. Risk of bias was assessed with the Newcastle-Ottawa Scale. Findings were synthesized narratively because study designs and outcomes were heterogeneous. RESULTS: Twenty-four studies including 512,768 participants met the inclusion criteria. Twenty-two (91.7%) reported positive associations between PTSD and accelerated biological aging across epigenetic clocks, telomere length, and transcriptional measures; GrimAge acceleration ranged from 1.83 to 2.53 years in veterans. Epigenome-wide association study findings implicated immune- and inflammation-related genes. Longitudinal and twin studies supported temporal precedence and partial independence from genetic confounding. However, 79.2% of studies were United States-based, 45.8% involved military or veteran samples, and most were cross-sectional, limiting generalizability and causal inference. CONCLUSIONS: PTSD is associated with faster biological aging across several biomarkers, but diverse longitudinal and intervention studies are needed before causality or reversibility can be established. More diverse long-term studies and treatment trials areneeded before these measures can guide routine care.