Mistreatment of Older Adults as A Risk Factor for Long‐Term Outcomes: A Systematic Review With Meta‐Analysis

Background Little is known about the relationship between long‐term outcomes and mistreatment of older adults (MOA). The aim is to examine the available literature to determine whether MOA could be considered a risk factor for long‐term outcomes. Methods A systematic search of Medline, Scopus, Web of Science, PubMed, and CENTRAL Cochrane was performed up to October 30, 2025. Observational studies evaluating the association between MOA and long‐term outcomes, such as hospitalization, mortality, chronic pain, physical and cognitive impairment, and depression in older people, and an available control were included. Bias risk was assessed using the ROBINS–E tool and certainty of evidence by GRADE. The protocol was registered in PROSPERO (ID 1070462). PRISMA guideline was followed. Estimates were pooled using random‐effects meta‐analysis. A p value less than 0.05 was considered statistically significant. Results The search carried out 74,797 articles in total. Twenty‐six observational studies involving 30,296,558 older adults (44,034 mistreated; 30,252,524 not mistreated older adults) were included. Most included studies were judged at low risk of bias, while the remaining ones raised some concerns. According to GRADE, the overall certainty of evidence was high. In a random‐effects model, the MOA was significantly associated with adverse long‐term outcomes (log OR: 0.75, 95% CI: 0.48–1.04; p < 0.0001), although substantial heterogeneity was observed ( I 2 = 98.85%). Associations remained significant across most subgroup analyses, and meta‐regression showed that mean age and percentage of women did not significantly influence the association. Conclusions MOA can be considered a significant risk factor for developing any long‐term outcome. It is associated with an increased likelihood of hospitalization, mortality, chronic pain, physical impairment, cognitive impairment, and depression. More attention should be paid to recognizing the underestimated phenomenon of MOA, which represents not only a human rights violation but also an additional risk factor for the health of the older population.