title: Intellectual activity and likelihood of subsequently improving or maintaining instrumental activities of daily living functioning in community-dwelling older Japanese: a longitudinal study.
abstract: OBJECTIVE
  To test the a priori hypothesis that increase or maintenance of the level of cognitive activity would be independently associated with a subsequent beneficial impact (i.e. improvement or maintenance) on instrumental activity of daily living (IADL) functioning.
  
  
  METHODS
  Observational study using 4-year longitudinal data from 1477 community-dwelling Japanese who were 66 years and older and living in Yoita town, a rural community located in the northwest along the Sea of Japan. Baseline assessment occurred in November 2000. Intellectual Activity and IADL were evaluated using the Tokyo Metropolitan Institute of Gerontology (TMIG) Index of Competence.
  
  
  RESULTS
  Increase or maintenance of exposure to intellectual activities over a period of 2 years was associated with increased likelihood of better IADL functioning trajectory (i.e. improvement or stability) over the subsequent 2 years (OR: 1.63; 95% CI: 1.03-2.56; p = 0.035), even after adjustment for major confounders.
  
  
  CONCLUSIONS
  This study documented a longitudinal, independent association of exposure to intellectual activities with better IADL functioning over time. These findings provide preliminary support for promotion of exposure to intellectual activities among older adults as an opportunity to prevent disability in the older segment of the population. Assessment of public health programs targeting such an opportunity is warranted.
authors.affiliation: Research Team for Social Participation and Health Promotion, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo. fujiwayo@tmig.or.jp
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Fujiwara
authors.forename: Paulo H M
authors.initials: PH
authors.lastname: Chaves
authors.forename: Hiroto
authors.initials: H
authors.lastname: Yoshida
authors.forename: Hidenori
authors.initials: H
authors.lastname: Amano
authors.forename: Taro
authors.initials: T
authors.lastname: Fukaya
authors.forename: Naoki
authors.initials: N
authors.lastname: Watanabe
authors.forename: Mariko
authors.initials: M
authors.lastname: Nishi
authors.forename: Sangyoon
authors.initials: S
authors.lastname: Lee
authors.forename: Hayato
authors.initials: H
authors.lastname: Uchida
authors.forename: Shoji
authors.initials: S
authors.lastname: Shinkai
mesh_terms: D000203:Activities of Daily Living; D000368:Aged / Q000523:psychology; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D003071:Cognition / Q000502:physiology*; D005260:Female; D015577:Geriatric Assessment; D006304:Health Status; D006801:Humans; D057187:Independent Living; D007360:Intelligence; D007361:Intelligence Tests; D007564:Japan; D007899:Leisure Activities; D008137:Longitudinal Studies; D008297:Male; D009043:Motor Activity; D012307:Risk Factors; D012424:Rural Population