Impact of evacuation onstrends in the prevalence, treatment, and control of hypertension before and after a disaster

Objective:After the Great East Japan Earthquake in 2011, the prevalence of cardiovascular disease risk factors increased in victims. We examined the trends in the prevalence, treatment, and control of hypertension before and after the disaster, as well as the impact of evacuation.Methods:Study participants were approximately 10000 men and 12000 women aged 40-74 years in each year from 2008 to 2014. All of the participants had lived in radiation evacuation zones prior to the Fukushima nuclear crisis. The age-standardized prevalence, treatment, and control of hypertension were calculated using the direct method. In a comparison of evacuees with nonevacuees, the proportion ratios and 95% confidence intervals for hypertension, treatment, and control were calculated by Poisson regression with robust error variance adjusted for covariates in each year after the disaster.Results:The age-standardized prevalence of hypertension peaked in 2012 at 48.8% in men and 39.0% in women. By 2014, the treatment and control of hypertension had increased to 66.3 and 67.1% in men, and 70.6 and 68.1% in women, respectively. The multiadjusted proportion ratios for the prevalence, treatment, and control of hypertension in any given year were 1.02-1.03, 0.99-1.05, and 0.93-1.06 in men, and 0.96-1.00, 0.99-1.05, and 1.06-1.11 in women, respectively.Conclusion:The prevalence of hypertension peaked 1 year after the disaster, while the treatment and control of hypertension increased thereafter. These results indicate that evacuation had little to no impact on the prevalence, treatment, and control of hypertension in the population of Fukushima Prefecture.