Characteristics of self-motion sensation after major earthquakes: An internet survey.

This study aimed to determine the characteristics and prognosis of new-onset swaying or dizziness, defined as self-motion sensation, following the 2024 Noto Peninsula earthquake in Japan and identify factors associated with persistent symptoms and disturbance in daily life. A cross-sectional, internet-based survey was conducted 2 months after the earthquake among 1,000 residents of the affected regions. The incidence and characteristics of self-motion sensation, its impact on daily life, and symptom duration were assessed in the survey. Logistic regression analyses were performed to identify demographic factors (age, sex, and region), individual characteristics (dizziness treatment history, proneness to motion sickness, and trait anxiety), and emotional responses (feelings of anxiety or fear induced by self-motion sensation) associated with life disturbance and persistent symptoms. Of 968 valid responses, 43% of participants reported a new-onset self-motion sensation following the earthquake. Symptoms were described as brief episodes of body swaying lasting less than 1 min, mostly occurring while sitting or standing still. Among those with self-motion sensation, 18.5% reported disturbance in daily life, and 24.5% continued to experience symptoms 2 months after the event. Younger age and emotional responses were significantly associated with life disturbance. Proximity to the epicenter and emotional response were associated with persistent symptoms. Self-motion sensation is common after major earthquakes and usually resolves spontaneously. However, a subset of individuals experiences persistent symptoms or disturbances in daily life. Emotional responses, particularly anxiety or fear triggered by self-motion sensation, play crucial roles in daily life impact and symptom persistence. Early recognition and targeted support for at-risk individuals may help prevent long-term impairment and improve post-disaster health outcomes.