title: Physical function mitigates the adverse effects of being thin on mortality in a free-living older Taiwanese cohort.
abstract: OBJECTIVE
  To examine the significance of underweight and physical function as well as their interaction on mortality in the aged.
  
  
  METHODS
  Prospective cohort.
  
  
  METHODS
  The Elderly Nutrition and Health Survey in Taiwan during 1999-2000.
  
  
  METHODS
  Total of 1435 representative free-living elders (739 men and 696 women).
  
  
  METHODS
  Body composition was assessed by various anthropometrics. Physical function score (PF, ranged 0-100) was derived from the SF-36(®). Death by December 31, 2006 was the outcome measure.
  
  
  RESULTS
  After 7.9 (median: 7.0) years follow-up, 381 (223 men, 158 women) of 1435 eligible participants had died. Those with the lowest PF (<45) had 3.43 (hazards ratio (HR), 95% confidence interval (CI) = 2.20-5.36) times the all-cause mortality risk of the highest PF (≥58). Interactions for PF and BMI (P =0.02) and for PF and wrist circumference (P =0.09) on death were found after controlling for potential confounders. Jointly, compared to normal-BMI-highest-PF, the greatest HR for death occurred where BMI <18.5 kg/m2 was combined with the lowest-PF after covariate adjustments (HR = 8.67, 95% CI = 3.77-20.0). Similarly, the lowest arm muscle circumference (MAMC)-PF had a HR of 5.22 compared to mid-MAMC-highest-PF. However, percent and absolute body fat, estimated by bioelectrical impedance, was comparable to non-sarcopenic individuals.
  
  
  CONCLUSIONS
  Thin elderly Taiwanese with sarcopenia, and less skeleton, are at the most risk of death, especially if physical function is limited.
authors.affiliation: School of Public Health, National Defense Medical Center, 161 Minchuan East Road, Sec. 6, Taipei 114, Taiwan, ROC. profmlw@nhri.org.tw
authors.forename: M-S
authors.initials: MS
authors.lastname: Lee
authors.forename: R C-Y
authors.initials: RC
authors.lastname: Chen
authors.forename: Y-H
authors.initials: YH
authors.lastname: Chang
authors.forename: Y-C
authors.initials: YC
authors.lastname: Huang
authors.forename: M L
authors.initials: ML
authors.lastname: Wahlqvist
mesh_terms: D000273:Adipose Tissue; D000368:Aged; D000369:Aged, 80 and over; D001132:Arm; D001823:Body Composition; D015992:Body Mass Index; D001842:Bone and Bones / Q000033:anatomy & histology; D002423:Cause of Death; D016001:Confidence Intervals; D005260:Female; D015577:Geriatric Assessment; D006306:Health Surveys; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000033:anatomy & histology; D010809:Physical Fitness; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D055948:Sarcopenia / Q000401:mortality*; D013624:Taiwan / Q000453:epidemiology; D013851:Thinness / Q000401:mortality*; D014953:Wrist