A meta-analysis on treatment efficacy of psychological interventions for mental disorders in individuals exposed to natural disasters

Natural disasters and extreme weather events have increased in recent years and are likely to increase further in the face of climate change. Many survivors of such events suffer from mental health complaints. We conducted a systematic review and meta-analysis on treatment efficacy of psychological interventions for mental disorders in survivors of natural disasters. Systematic database searches resulted in the inclusion of ten randomised controlled trials with 613 participants (37.8% women). Nine of these trials focused on posttraumatic stress disorder (PTSD), whereas one trial included individuals with alcohol dependence. Studies were conducted in China, Turkey, Iran, Pakistan, and Thailand. Four trials included children and adolescents who received group treatments, whereas six trials included adults who received individual treatments. Most interventions consisted of cognitive-behavioural therapy (k = 7). Results suggest a significant short-term efficacy of interventions for PTSD compared to passive control conditions (g = 1.44; 95% CI 0.53-2.35, k = 7). The long-term efficacy after an average of 8 weeks post-treatment remained significant (g = 0.59; 95% CI 0.25-0.93, k = 4). The trials furthermore yielded significant treatment effects regarding comorbid depression compared to control conditions for both short-term and long-term outcomes. Heterogeneity in effect sizes between individual studies was small to moderate. Our findings suggest that psychological interventions, especially cognitive-behavioural therapy, can effectively treat PTSD and comorbid mental health problems in survivors of natural disasters. Nonetheless, conclusions are limited by the small number of trials and the strong focus on PTSD.