PLoS ONE (Jan 2014)

Leg extension power is a pre-disaster modifiable risk factor for post-traumatic stress disorder among survivors of the Great East Japan Earthquake: a retrospective cohort study.

  • Haruki Momma,
  • Kaijun Niu,
  • Yoritoshi Kobayashi,
  • Cong Huang,
  • Atsushi Otomo,
  • Masahiko Chujo,
  • Hiroko Tadaura,
  • Ryoichi Nagatomi

DOI
https://doi.org/10.1371/journal.pone.0096131
Journal volume & issue
Vol. 9, no. 4
p. e96131

Abstract

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BackgroundPost-traumatic stress disorder (PTSD) is a common psychological problem following natural disasters. Although pre-disaster risk factors are important for early detection and proactive support, the examination of such has been limited to sociodemographic factors, which were largely unaffected by the disasters. We examined the association between pre-disaster physical functioning and lifestyle and PTSD symptoms five months after the earthquake in the Great East Japan Earthquake survivors who were participating in a pre-existing cohort study.MethodsWe designed a retrospective cohort study of a cooperative association in Sendai from August 2010 to August 2011. In 2010, lifestyle, physical condition, and sociodemographic factors were examined by self-reported questionnaires completed by 522 employees of this organization. We also measured the leg extension power of all the participants. PTSD symptoms were evaluated by the Japanese version of the Impact of Event Scale-Revised (IES-R-J) following the earthquake of 2011.ResultsIn multivariate linear regression analysis, leg extension power (β = -0.128, P = 0.025), daily drinking (β = 0.203, P = 0.006), and depressive symptoms (β = 0.139, P = 0.008) were associated with total score of the IES-R-J among men. Moreover, for the IES-R-J subscale, leg extension power was also negatively associated with Intrusion (β = -0.114, P = 0.045) and Hyperarousal (β = -0.163, P = 0.004) after adjusting for all other significant variables. For women, hypertension (β = 0.226, P = 0.032) and depressive symptoms (β = 0.205, P = 0.046) were associated with the total score of the IES-R-J.ConclusionsLeg extension power is a potentially modifiable pre-disaster risk factor among men for attenuating the severity of PTSD symptoms associated with great disasters such as the Great East Japan Earthquake among men.