Effect of the 2016 Kumamoto earthquakes on preventable hospital admissions: a retrospective cohort study in Japan

BACKGROUND AND OBJECTIVES: The Kumamoto earthquakes struck Kumamoto prefecture, in the southwest part of Japan in April 2016. Physical and mental disorders presenting to hospital increased after the 2016 Kumamoto earthquakes. Impaired access to primary care due to the earthquakes may have contributed to this increase. However, it is not known whether the 2016 Kumamoto earthquakes affected access to primary care. The objective of the present study was to investigate the impact of the 2016 Kumamoto earthquakes on short-term health conditions by analysing ambulatory care sensitive conditions (ACSCs), using administrative data from Kumamoto prefecture. DESIGN: A retrospective cohort study. SETTING: Residents enrolled in National Health Insurance or Late Elders’ Health Insurance from Kumamoto prefecture, Japan. PARTICIPANTS: All hospital admissions due to ACSCs between 15 March and 16 May in each year from 2013 to 2016. OUTCOME MEASURES: ACSCs are defined as conditions for which appropriate primary care interventions could prevent admission to the hospital. RESULTS: We identified a total of 7921, 18 763 and 85 436 admissions for vaccine, acute and chronic preventable ACSCs, respectively, during the study period. Admissions within 7 days after the 2016 Kumamoto earthquakes increased to 32.6% (10.2, 59.5), 44.1% (27.0, 63.5) and 27.7% (20.2, 35.6) for vaccine-preventable, acute and chronic ACSCs, respectively. However, admissions for ACSCs did not change significantly 30 days after the earthquakes. CONCLUSION: The 2016 Kumamoto earthquakes were associated with increased hospital admissions for ACSCs. The impact of the earthquakes on admissions for ACSCs did not persist for more than 7 days.