Disaster-related trauma and blood pressure among young children: a follow-up study after Great East Japan earthquake

The 11 March 2011 earthquake and tsunami in Japan resulted in similar to 19,000 lost lives and the displacement of nearly a quarter million people owing to extensive property damage and evacuation from the nuclear meltdown in Fukushima. We sought to prospectively examine whether exposure to disaster-related trauma affected blood pressure levels among young children. We sampled children in three affected prefectures (Miyagi, Fukushima, Iwate) and one unaffected prefecture (Mie). The participants (mean age 6.6 years) and their caregivers answered a baseline survey (N = 320) and a follow-up survey 4 years after the earthquake (N = 227, follow-up rate 71%). Disaster-related trauma was assessed at the baseline, and blood pressure measurements were taken at the follow-up. We converted blood pressure data into age/sex/height-specific z-scores. In linear regression models, we controlled for body mass index, income, age, sex, and housing situation (living in the same house as before the disaster, in a shelter, or in a new house). The number of traumatic experiences was related to diastolic blood pressure in a dose-dependent manner but was not related to systolic blood pressure. Children reporting four or more traumatic experiences had marginally significant elevated diastolic blood pressure (beta = 0.43, p = 0.059). Among specific types of disaster trauma, witnessing a fire was significantly related to higher diastolic blood pressure (beta = 0.60, p = 0.009). In conclusion, disaster-related trauma was associated with higher diastolic blood pressure among young children 4 years after the traumatic events.