title: Diabetes, inflammation, and functional decline in older adults: findings from the Health, Aging and Body Composition (ABC) study.
abstract: OBJECTIVE
  Age, diabetes, and elevated inflammatory markers independently increase the risk of functional decline. We examined the effect of C-reactive protein (CRP) and interleukin-6 (IL-6) on the incident mobility limitation in older adults with and without diabetes.
  
  
  METHODS
  We analyzed data from a cohort of 2,895 well-functioning adults aged 70-79 years, followed for development of persistent functional limitation over 3.5 years. Participants were assessed for the presence of diabetes according to fasting glucose and/or hypoglycemic medication use and were divided into three equal groups (tertiles) according to level of CRP or IL-6. Persistent functional limitation was defined as difficulty climbing 10 steps or walking one-quarter mile on two consecutive semiannual assessments.
  
  
  RESULTS
  At baseline, 702 participants (24%) had diabetes. CRP values were (median +/- SD) 2.8 +/- 4.4 versus 3.7 +/- 5.4 for those with normal glucose and diabetes, respectively (P < 0.001). The unadjusted incidence of functional limitation associated with increased levels of CRP and IL-6 was greater among participants with diabetes. After adjusting for clinical and demographic covariates, persistent functional limitation for the highest tertile was greater compared with that for the lowest tertile of CRP or IL-6 for those with and without diabetes. CRP hazard ratios (HRs) were 1.7 (95% CI 1.2-2.3) versus 1.4 (1.1-1.6), respectively. IL-6 HRs were 1.8 (1.3-2.5) versus 1.6 (1.4-2.0), respectively.
  
  
  CONCLUSIONS
  In initially high-functioning older adults, those with diabetes and higher inflammatory burden had an increased risk of functional decline. Interventions at early stages to reduce inflammation may preserve function in these individuals.
authors.affiliation: Department of Medicine, Vanderbilt University Medical Center/GRECC, 1310 24th Ave. South, Room 4B111, Nashville, TN 37212, USA. kathleen.figaro@vanderbilt.edu
authors.forename: M Kathleen
authors.initials: MK
authors.lastname: Figaro
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Kritchevsky
authors.forename: Helaine E
authors.initials: HE
authors.lastname: Resnick
authors.forename: Ronald I
authors.initials: RI
authors.lastname: Shorr
authors.forename: Javed
authors.initials: J
authors.lastname: Butler
authors.forename: Ayumi
authors.initials: A
authors.lastname: Shintani
authors.forename: Brenda W
authors.initials: BW
authors.lastname: Penninx
authors.forename: Eleanor M
authors.initials: EM
authors.lastname: Simonsick
authors.forename: Bret H
authors.initials: BH
authors.lastname: Goodpaster
authors.forename: Anne B
authors.initials: AB
authors.lastname: Newman
authors.forename: Ann V
authors.initials: AV
authors.lastname: Schwartz
authors.forename: Tamara B
authors.initials: TB
authors.lastname: Harris
mesh_terms: D000368:Aged; D000375:Aging; D001823:Body Composition; D002097:C-Reactive Protein / Q000378:metabolism; D015331:Cohort Studies; D003920:Diabetes Mellitus / Q000097:blood* / Q000503:physiopathology; D005260:Female; D006304:Health Status; D006801:Humans; D007249:Inflammation / Q000097:blood* / Q000503:physiopathology; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D051346:Mobility Limitation; D015999:Multivariate Analysis
chemical_list: D015850:Interleukin-6; D002097:C-Reactive Protein