MON-336 LONGITUDINAL ANALYIS OF KIDNEY FUNCTION AND POSSIBLE FACTORS INVOLVED AFTER THE GREAT EAST JAPAN EARTHQUAKE AMONG RESIDENTS NEAR THE FUKUSHIMA DAIICHI NUCLEAR POWER PLANT

Abstract

In March 2011, the Great East Japan Earthquake and subsequent tsunami seriously damaged the northeast Japanese Pacific coast, including a level 7 accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP). Thousands of residents of Futaba District (where FDNPP is located) evacuated because of possible radioactive contamination. Seven years after the accident, evacuated residents are coming back to Futaba District due to the decreased exposure to radioactivity. The long-term effects of the Great East Japan Earthquake and the FDNPP accident on the kidney function of residents of Futaba District remained unknown. We performed yearly medical examinations of Futaba District residents aged ≥40 years from 2011 to 2016. Approximately 15,000 residents underwent the medical examination every year. Of these, 4,712 had evacuated the district after the Earthquake. The prevalence of hypertension defined as systolic blood pressure >140 mmHg was more than 40% in the days right after the Earthquake, and the prevalence gradually decreased to less than 30% in 2014. The prevalence thereafter increased again over the next 2 years. The prevalence of glycosuria showed a pattern similar to that of hypertension. The prevalence of residents with HbA1c >6.0% and the mean uric acid level increased throughout the 6-year examination. The prevalence of proteinuria remained unchanged, while that of hematuria slightly decreased. The mean creatine and estimated glomerular filtration rate values showed no specific alteration tendency, but the prevalence of chronic kidney disease (CKD) stage G3 or worse kept increasing throughout the 6-year examination. Interestingly, the individuals who evacuated were associated with a significantly higher risk of a new onset of CKD stage G3 or worse compared to the residents who never evacuated, even after the adjustment of background factors. Various factors including psychological stress by the disaster itself, psychological stress due to life as an evacuee, and the decreased amount of outdoor activity were likely to be associated with the changes in the health condition of the inhabitants of Futaba District. Those factors are also likely to have slight but significant influences on kidney function. Our analyses identified no factors that appeared to be directly affected by radiation exposure