RESUMEN
BACKGROUND: Despite the high occurrence of floods in Iran, its psychological consequences have been less discussed. The present paper addresses the prevalence of Post-traumatic Stress Disorder (PTSD) and its determinants among the affected adults by the huge flood of 2019. METHODS: An analytical cross-sectional study was conducted through household face-to-face surveys in August and September 2019. Individuals who were affected by floods and were at least 16 years old were randomly selected from three provinces in Iran: Lorestan and Khuzestan in the west and southwest, and Golestan in the northeast. The questionnaire of demographic and flood related variables in addition to the Impact of Event Scale-Revised (IES-R) were utilized to collect the data. We applied a complex sample analysis to describe the prevalence of PTSD and logistic regression analyses to find its determinants. RESULTS: Out of the 2,305 individuals approached for surveys, 1,671 (72.5%) adults affected by the floods participated in the study. The majority of participants were housewives, married, had either no formal education or primary education, and resided in rural areas. The prevalence of PTSD in the participants was 24.8% (CI 95%: 20.7-28.8%) and was significantly higher in Lorestan province (39.7%, P < 0.001). Determinants of PTSD, were unemployment (adjusted odds ratio [AOR] = 3.53, CI 95%: 1.38-9.00), primary (AOR = 2.44, CI 95%: 1.10-5.41) or high school (AOR = 2.35, CI 95%: 1.25-4.40) education (vs. university), a history of mental disorders (AOR = 2.36, CI 95%: 1.22-4.58), high damage to assets (AOR = 2.29, CI 95%: 1.40-3.75), limited access to health care services after the flood (AOR = 1.95, CI 95%: 1.20-3.19), not receiving compensation for flood damage (AOR = 1.94, CI 95%: 1.01-3.83), high wealth index (AOR = 1.90, CI 95%: 1.23-2.93), and flooded house with a height of more than one meter (AOR = 1.66, CI 95%: 1.02-2.76). CONCLUSION: Results show a notable prevalence of PTSD, especially in Lorestan province, among adults affected by floods. Determinants of PTSD include unemployment, lower education, psychiatric history, extensive property damage, limited post-flood healthcare access, lack of compensation, and increased flood exposure. We recommend adopting an inclusive screening approach for high-risk groups and developing appropriate therapeutic and supportive interventions.