title: Natural history and predictors of faster glomerular filtration rate decline in a referred population of older patients with type 2 diabetes mellitus.
abstract: OBJECTIVE
  To study the natural history and predictors of faster glomerular filtration rate (GFR) decline in a referred population of older patients (aged ≥ 65 years) with type 2 diabetes mellitus.
  
  
  METHODS
  A retrospective medical record analysis in an outpatient diabetes clinic for older patients. Baseline characteristics and blood pressure readings for each clinic visit were recorded. All laboratory results were downloaded from the central database of the pathology laboratory. Annual rate of GFR decline was calculated by linear regression analysis as the slope per year for each individual. Patients were then divided into 2 groups on either side of the mean GFR decline. Group 1 had a slower GFR decline (below the mean value) and group 2 had a faster GFR decline (above the mean value). Five variables were investigated as predictors of faster decline in GFR: cardiovascular disease (CVD), hypertension, diabetes control, use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, and albuminuria.
  
  
  RESULTS
  The study included 100 patients with a mean age of 69.5 (standard deviation [SD], 3.9) years on referral, and 54 patients were men. The mean duration of study was 14.4 (SD, 2.0) years. A total of 3908 GFR results were downloaded during the study. The mean annual rate of GFR decline was 1.5 (SD, 1.2) mL/min/1.73 m2. Glomerular filtration rate values were comparable in both groups on first referral. Mean annual rate of GFR decline was 2.6 (SD, 0.9) mL/min/1.73 m2 in group 2 compared with 0.7 (SD, 0.5) mL/min/1.73 m2 (P < 0.001) in group 1. Development of CVD was the only independent predictor of faster renal function decline (odds ratio, 2.9; 95% CI, 1.1-7.6; P = 0.03).
  
  
  CONCLUSIONS
  Cardiovascular disease is an independent risk factor for faster decline in GFR in older patients with type 2 diabetes mellitus.
authors.affiliation: Department of Elderly Medicine, Rotherham General Hospital, Rotherham, UK. ahmedhafiz@hotmail.com
authors.forename: Ahmed H
authors.initials: AH
authors.lastname: Abdelhafiz
authors.forename: Evelyn
authors.initials: E
authors.lastname: Tan
authors.forename: Christopher
authors.initials: C
authors.lastname: Levett
authors.forename: Joanna
authors.initials: J
authors.lastname: Minchin
authors.forename: Meguid El
authors.initials: ME
authors.lastname: Nahas
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology*; D018450:Disease Progression; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D016014:Linear Models; D008297:Male; D015999:Multivariate Analysis; D051436:Renal Insufficiency, Chronic / Q000453:epidemiology* / Q000517:prevention & control; D012189:Retrospective Studies; D012307:Risk Factors; D006113:United Kingdom / Q000453:epidemiology