Long term mental health trajectories after disasters and pandemics: A multilingual systematic review of prevalence, risk and protective factors.

The patterns of long-term psychological response after disasters and pandemics remain unclear. We aimed to determine the trajectories for post-traumatic stress symptoms (PTSS), depression and anxiety prevalence following disasters and pandemic exposure; and identify associated risk and protective factors. A systematic review of the English, Chinese, and Japanese longitudinal mental health literature was conducted. We searched Cochrane, MEDLINE, ProQuest, PsycINFO, PubMed, Web of Science, and CINAHL (English), CNKI and SINOMED (Chinese) and CiNii (Japanese) for studies published between January 2000 and May 2022. Following a pre-specified protocol (PROSPERO: CRD42020206424), conditional linear growth curve models and ANOVA analyses were conducted. The search identified 77,891 papers, with a final sample of 234: 206 English, 24 Chinese, and 4 Japanese-language papers. PTSS rates improved for all ages (p = .018, eta2 = 0.035). In contrast, depression and anxiety prevalence remained elevated for years following exposure (p = .424, eta2 = 0.019 and p = .051, eta2 = 0.064, respectively), with significantly higher rates for children and adolescents (p < .005, eta2 > 0.056). Earthquakes and pandemics were associated with higher prevalence of PTSS (p < .019, eta2 > 0.019). Multi-level risk and protective factors were identified. The chronicity of mental health outcomes highlights a critical need for tailored, sustainable mental health services, particularly for children and adolescents, in disaster- and pandemic-affected settings.