title: Predictors of decline in IADL functioning among older survivors following the Great East Japan earthquake: A prospective study.
abstract: We described associations between the type of disaster experience and change in instrumental activities of daily living among older adult survivors before-after a terrible disaster.
  
  
  
  The study took advantage of a "natural experiment" afforded by the Japan Gerontological Evaluation Study (JAGES), a nationwide cohort study established in 2010, seven months prior to the earthquake and tsunami. A follow-up survey was conducted in 2013. This study was conducted in Iwanuma, which was directly struck by tsunami. Our sample comprised community-dwelling aged survivors in Iwanuma who responded to questions about personal circumstances and functional status both before and after the disaster (N = 3547). Personal experiences of earthquake and tsunami damage was used as an exposure variable. The outcome was changes in self-reported 13-item instrumental activities of daily living (IADL), which was assessed both before and after the disaster.
  
  
  
  Among the participants, 931 reported losing family member(s) to the disaster, while a further 549 reported losing friend(s). More than half of the participants reported any damage to their houses while approximately 1 in 8 lost their car(s). The multivariable OLS regression revealed that complete house loss and disruption of internal medicine were associated with significantly worse IADL: -0.67 points (95%CI: -0.99, -0.34) for entirely destroyed homes; -0.40 points (95% CI: -0.71, -0.092) for disruption of internal medicine. By contrast, loss of family/friends/pets/cars and disruption to the other medical service were not associated with decline in IADL.
  
  
  
  Complete house loss and disruption of access to internal medicine after a disaster were associated with significant adverse impact on decline in physical and cognitive functions 2.5 years after the disaster, while loss of family/friends was not.
authors.affiliation: Harvard T.H. Chan School of Public Health, Department of Social and Behavioral Sciences, Boston, USA; Tohoku University Graduate School of Dentistry, Department of International and Community Oral Health, Sendai, Japan. Electronic address: tsubo828@gmail.com.
authors.forename: Toru
authors.initials: T
authors.lastname: Tsuboya
authors.affiliation: Tohoku University Graduate School of Dentistry, Department of International and Community Oral Health, Sendai, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Aida
authors.affiliation: Harvard T.H. Chan School of Public Health, Department of Social and Behavioral Sciences, Boston, USA.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Hikichi
authors.affiliation: Harvard T.H. Chan School of Public Health, Department of Social and Behavioral Sciences, Boston, USA.
authors.forename: S V
authors.initials: SV
authors.lastname: Subramanian
authors.affiliation: Chiba University, Center for Preventive Medical Sciences, Chiba, Japan.
authors.forename: Katsunori
authors.initials: K
authors.lastname: Kondo
authors.affiliation: Tohoku University Graduate School of Dentistry, Department of International and Community Oral Health, Sendai, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Osaka
authors.affiliation: Harvard T.H. Chan School of Public Health, Department of Social and Behavioral Sciences, Boston, USA.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kawachi
mesh_terms: D000203:Activities of Daily Living / Q000523:psychology*; D000368:Aged; D000369:Aged, 80 and over; D004190:Disasters / Q000706:statistics & numerical data; D055866:Earthquakes / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D011446:Prospective Studies; D057566:Self Report; D011795:Surveys and Questionnaires; D017741:Survivors / Q000523:psychology / Q000706:statistics & numerical data*
keywords: Independent living; Japan; Natural disaster; Natural experiment