Citation

Shiba K, Daoud A, Hikichi H, Yazawa A, Aida J, Kondo K, Kawachi I. Am. J. Epidemiol. 2022; ePub(ePub): ePub.

Copyright

(Copyright © 2022, Oxford University Press)

DOI

10.1093/aje/kwac187

PMID

36255224

Abstract

This study examined heterogeneity in the association between disaster-related home loss and functional limitations of older adults and identified characteristics of vulnerable sub-populations. Data were from a prospective cohort study of Japanese older survivors of the 2011 Japan Earthquake. Complete home loss was objectively assessed. Outcomes in 2013 (n=3,350) and 2016 (n=2,664) included certified physical disability levels, self-reported Activities of Daily Living, and Instrumental Activities of Daily Living. We estimated population average associations between home loss and functional limitations via targeted maximum likelihood estimation with SuperLearning and its heterogeneity via the generalized random forest algorithm. We adjusted for survivors' 55 characteristics from the baseline survey conducted seven months before the disaster. While home loss was consistently associated with increased functional limitations on average, there was evidence of effect heterogeneity for all outcomes. Comparing the most and least vulnerable groups, the most vulnerable group tended to be older, not married, living alone, and not working, with pre-existing health problems before the disaster. Individuals who were less educated but had higher income also appeared vulnerable for some outcomes. Our inductive approach for effect heterogeneity using machine learning algorithm uncovered large and complex heterogeneity in post-disaster functional limitations among Japanese older survivors.

Language: en

Keywords

machine learning; natural disaster; causal inference; effect heterogeneity; functional limitation; instrumental activities of daily living