title: Screening for frailty phenotype with objectively-measured physical activity in a west Japanese suburban community: evidence from the Sasaguri Genkimon Study.
abstract: BACKGROUND
  The low physical activity domain of the frailty phenotype has been assessed with various self-reported questionnaires, which are prone to possible recall bias and a lack of diagnostic accuracy. The primary purpose of this study was to define the low physical activity domain of the frailty phenotype using accelerometer-based measurement and to evaluate the internal construct validity among older community-dwellers. Secondly, we examined potential correlates of frailty in this population.
  
  
  METHODS
  We conducted a cross-sectional study of 1,527 community-dwelling older men and women aged 65 and over. Data were drawn from the baseline survey of the Sasaguri Genkimon Study, a cohort study carried out in a west Japanese suburban community. Frailty phenotypes were defined by the following five components: unintentional weight loss, low grip strength, exhaustion, slow gait speed, and low physical activity. Of these criteria, physical activity was objectively measured with a tri-axial accelerometer. To confirm our measure's internal validity, we performed a latent class analysis (LCA) to assess whether the five components could aggregate statistically into a syndrome. We examined the correlates of frailty using multiple stepwise logistic regression models.
  
  
  RESULTS
  The estimated prevalence of frailty was 9.3% (95% confidence intervals, CI, 8.4-11.2); 43.9% were pre-frail (95% CI, 41.5-46.4). The percentage of low physical activity was 19.5%. Objectively-assessed physical activity and other components aggregated statistically into a syndrome. Overall, increased age, poorer self-perceived health, depressive and anxiety symptoms, not consuming alcohol, no engagement in social activities, and cognitive impairment were associated with increased odds of frailty status, independent of co-morbidities.
  
  
  CONCLUSIONS
  This study confirmed the internal construct validity of the frailty phenotype that defined the low energy expenditure domain with the objective measurement of physical activity. Accelerometry may potentially standardize the measurement of low physical activity and improve the diagnostic accuracy of the frailty phenotype criteria in primary care setting. The potential role of factors associated with frailty merits further studies to explore their clinical application.
authors.affiliation: Department of Health Behavior and Sciences, Graduate School of Human-Environment Studies, Kyushu University, Kasuga City, Japan. sanmei.chen.033@s.kyushu-u.ac.jp.
authors.forename: Sanmei
authors.initials: S
authors.lastname: Chen
authors.affiliation: Department of Health Behavior and Sciences, Graduate School of Human-Environment Studies, Kyushu University, Kasuga City, Japan. honda-t@students.ihs.kyushu-u.ac.jp.
authors.forename: Takanori
authors.initials: T
authors.lastname: Honda
authors.affiliation: Department of Health Behavior and Sciences, Graduate School of Human-Environment Studies, Kyushu University, Kasuga City, Japan. chentwhy@gmail.com.
authors.forename: Tao
authors.initials: T
authors.lastname: Chen
authors.affiliation: Department of Health Behavior and Sciences, Graduate School of Human-Environment Studies, Kyushu University, Kasuga City, Japan. kenji170@gmail.com.
authors.forename: Kenji
authors.initials: K
authors.lastname: Narazaki
authors.affiliation: Department of Health Behavior and Sciences, Graduate School of Human-Environment Studies, Kyushu University, Kasuga City, Japan. yuka_haeuchi@yahoo.co.jp.
authors.forename: Yuka
authors.initials: Y
authors.lastname: Haeuchi
authors.affiliation: Department of Health Behavior and Sciences, Graduate School of Human-Environment Studies, Kyushu University, Kasuga City, Japan. zamzabila@hotmail.com.
authors.forename: Atin
authors.initials: A
authors.lastname: Supartini
authors.affiliation: Department of Health Behavior and Sciences, Graduate School of Human-Environment Studies, Kyushu University, Kasuga City, Japan. shuzo@ihs.kyushu-u.ac.jp.|Faculty of Arts and Science, 6-1 Kasuga koen, Kasuga City, Fukuoka Prefecture, 816-8580, Japan. shuzo@ihs.kyushu-u.ac.jp.
authors.forename: Shuzo
authors.initials: S
authors.lastname: Kumagai
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D003430:Cross-Sectional Studies; D005260:Female; D016330:Frail Elderly / Q000706:statistics & numerical data*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D010641:Phenotype; D015995:Prevalence; D057566:Self Report; D013383:Suburban Population