title: Better glycemic control is associated with maintenance of lower-extremity function over time in Mexican American and European American older adults with diabetes.
abstract: OBJECTIVE
  Diabetes is a major cause of functional decline among older adults, but the role of glycemic control remains unclear. This article assesses whether better glycemic control is associated with better maintenance of lower-extremity function over time in older adults with diabetes.
  
  
  METHODS
  Participants (n = 119) in the San Antonio Longitudinal Study of Aging, ages 71-85, who met American Diabetes Association diabetes criteria were followed over a 36-month period. Seven measures of A1C (HbA(1c)) were obtained at 6-month intervals; three measures of lower-extremity function were obtained at 18-month intervals using the Short Physical Performance Battery (SPPB). A two-step analytic approach was used, first, to identify distinct glycemic control classes using latent growth mixture modeling and, second, to examine trajectories of lower-extremity function based on these classes using path analysis.
  
  
  RESULTS
  Two glycemic control classes were identified: a poorer control class with higher means (all >7%) and higher within-subject variability in HbA(1c) and a better control class with lower means (all <7%) and lower within-subject variability. The short-term and long-term maintenance of lower-extremity function, assessed by the association between the first and second SPPB measures and the first and third SPPB measures, were both greater in the better control class than in the poorer control class.
  
  
  CONCLUSIONS
  Among older adults with diabetes, better glycemic control may improve both short-term and long-term maintenance of lower-extremity function.
authors.affiliation: Department of Epidemiology and Biostatistics, University of Texas Health Science Center at San Antonio, Texas, USA.
authors.forename: Chen-Pin
authors.initials: CP
authors.lastname: Wang
authors.forename: Helen P
authors.initials: HP
authors.lastname: Hazuda
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D048909:Diabetes Complications / Q000188:drug therapy / Q000208:ethnology*; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D006943:Hyperglycemia / Q000188:drug therapy / Q000208:ethnology*; D015994:Incidence; D007866:Leg; D008137:Longitudinal Studies; D008297:Male; D017058:Mexican Americans / Q000706:statistics & numerical data*; D051346:Mobility Limitation; D009043:Motor Activity; D015995:Prevalence; D044465:White People / Q000706:statistics & numerical data*