Mortality Risk amongst Nursing Home Residents Evacuated after the Fukushima Nuclear Accident: A Retrospective Cohort Study

Abstract

BackgroundSafety of evacuation is of paramount importance in disaster planning for elderly people; however, little effort has been made to investigate evacuation-related mortality risks. After the Fukushima Daiichi Nuclear Plant accident we conducted a retrospective cohort survival survey of elderly evacuees.MethodsA total of 715 residents admitted to five nursing homes in Minamisoma city, Fukushima Prefecture in the five years before 11th March 2011 joined this retrospective cohort study. Demographic and clinical characteristics were drawn from facility medical records. Evacuation histories were tracked until the end of 2011. The evacuation's impact on mortality was assessed using mortality incidence density and hazard ratios in Cox proportional hazards regression.ResultsOverall relative mortality risk before and after the earthquake was 2.68 (95% CI: 2.04–3.49). There was a substantial variation in mortality risks across the facilities ranging from 0.77 (95% CI: 0.34–1.76) to 2.88 (95% CI: 1.74–4.76). No meaningful influence of evacuation distance on mortality was observed although the first evacuation from the original facility caused significantly higher mortality than subsequent evacuations, with a hazard ratio of 1.94 (95% CI: 1.07–3.49).ConclusionHigh mortality, due to initial evacuation, suggests that evacuation of the elderly was not the best life-saving strategy for the Fukushima nuclear disaster. Careful consideration of the relative risks of radiation exposure and the risks and benefits of evacuation is essential. Facility-specific disaster response strategies, including in-site relief and care, may have a strong influence on survival. Where evacuation is necessary, careful planning and coordination with other nursing homes, evacuation sites and government disaster agencies is essential to reduce the risk of mortality.

Evacuation Effect on Excess Mortality Among Institutionalized Elderly After the Fukushima Daiichi Nuclear Power Plant Accident

“…In three of 5 facilities, initial evacuation significantly elevated mortality after the disaster 3) . Results of previous studies 1,3) are consistent with our data.…”

Postnuclear disaster evacuation and chronic health in adults in Fukushima, Japan: a long-term retrospective analysis

“…22 Of those who were made to evacuate, more than 70 000 are still subject to a range of evacuation measures as of 5 September 2015, following slight lifts of the instructions. 23 Yasumura et al 24 and Nomura et al 25 reported threefold increase in mortality among evacuated nursing home residents up to 1 year following the incident. Elevated values of metabolic markers, including body mass index (BMI), blood pressure, glucose metabolism, lipid metabolism and liver function, were also demonstrated in evacuees, by Satoh et al 26 and Tsubokura et al, 27 1 year after the incident, suggesting worsening chronic health conditions.…”

Limited Internal Radiation Exposure Associated with Resettlements to a Radiation-Contaminated Homeland after the Fukushima Daiichi Nuclear Disaster

“…For instance, the blanket evacuation technique caused a dramatically acute increase in mortality among residents of elderly nursing homes in the Fukushima area[4]. Moreover, evacuation could have long-term adverse health effects; prolonged life as evacuees could represent physical, mental and socioeconomic burdens[5].…”