Post-disaster psychosocial and physical determinants of perceived chewing difficulty among fukushima residents: the Fukushima Health Management Survey

BACKGROUND: Oral functions, including chewing and occlusal function, are associated with nutritional intake, cognitive function, muscle strength, and balance. Therefore, maintaining oral functions is crucial for extending healthy life expectancy. This study aimed to identify factors associated with perceived chewing difficulty as a functional oral outcome and its worsening following the Great East Japan Earthquake, with a particular focus on disaster-related psychosocial factors. METHODS: This cross-sectional study investigated self-reported chewing difficulty, psychological factors (e.g., traumatic reactions and psychological distress), disaster-related experiences (e.g., evacuation and experiences related to the nuclear accident, job loss, loss of a close person), medical history, and lifestyle factors among 64,188 residents aged 16-101 years who experienced the earthquake on March 11, 2011. Multinomial logistic regression analyses were performed to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for each factor associated with prevalent and exacerbated chewing difficulty. RESULTS: The proportions of participants with prevalent and exacerbated chewing difficulty were 2.8% and 0.31%, respectively. Multivariate-adjusted ORs (95% CIs) for factors associated with exacerbated chewing difficulty were as follows: post-traumatic stress disorder symptoms, 3.23 (2.35-4.43); psychological distress, 3.71 (2.71-5.09); experience of the nuclear accident, 1.57 (1.14-2.17); job loss, 1.47 (1.08-2.02); history of mental illness, 2.94 (2.00-4.32); dyslipidemia, 1.47 (1.06-2.05); and current exercise habit, 0.60 (0.44-0.83). CONCLUSIONS: These findings suggest that previously underexplored post-disaster psychosocial factors, including PTSD symptoms, experience of the nuclear accident, and job loss, as well as physical factors such as a history of mental illness and dyslipidemia, are associated with perceived chewing difficulty. In contrast, regular exercise habits were negatively associated with perceived chewing difficulty and may have a preventive role.