title: Blood pressure components and decline in kidney function in community-living older adults: the Cardiovascular Health Study.
abstract: BACKGROUND
  Although hypertension contributes to kidney dysfunction in the general population, the contributions of elevated systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse pressure (PP) to kidney function decline in community-dwelling older adults are unknown.
  
  
  METHODS
  We used linear and logistic regression to examine the separate and combined associations of SBP, DBP, and PP at baseline with kidney function decline among 4,365 older adults in the Cardiovascular Health Study. We used cystatin C to estimate glomerular filtration rate on 3 occasions over 7 years of follow-up. We defined rapid decline ≥ 3ml/min/year.
  
  
  RESULTS
  Average age was 72.2 and mean (standard deviation) SBP, DBP, and PP were 135 (21), 71 (11), and 65 (18) mm Hg, respectively. SBP and PP, rather than DBP, were most significantly associated with kidney function decline. In adjusted linear models, each 10-mm Hg increment in SBP and PP was associated with 0.13ml/min/year (-0.19, -0.08, P < 0.001) and 0.15-ml/min/year faster decline (-0.21, -0.09, P < 0.001), respectively. Each 10-mm Hg increment in DBP was associated with a nonsignificant 0.10-ml/min/year faster decline (95% confidence interval, -0.20, 0.01). In adjusted logistic models, SBP had the strongest associations with rapid decline, with 14% increased hazard of rapid decline (95% confidence interval, 10% to 17%, P < 0.01) per 10mm Hg. In models combining BP components, only SBP consistently had independent associations with rapid decline.
  
  
  CONCLUSIONS
  Our findings suggest that elevated BP, particularly SBP, contributes to declining kidney function in older adults.
authors.affiliation: Divisions of Nephrology and of Family and Preventive Medicine, University of California, San Diego, and Veterans' Affairs Medical Center, San Diego, CA, USA. drifkin@ucsd.edu
authors.forename: Dena E
authors.initials: DE
authors.lastname: Rifkin
authors.forename: Ronit
authors.initials: R
authors.lastname: Katz
authors.forename: Michel
authors.initials: M
authors.lastname: Chonchol
authors.forename: Michael G
authors.initials: MG
authors.lastname: Shlipak
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Sarnak
authors.forename: Linda F
authors.initials: LF
authors.lastname: Fried
authors.forename: Anne B
authors.initials: AB
authors.lastname: Newman
authors.forename: David S
authors.initials: DS
authors.lastname: Siscovick
authors.forename: Carmen A
authors.initials: CA
authors.lastname: Peralta
mesh_terms: D000368:Aged; D001794:Blood Pressure / Q000502:physiology*; D015331:Cohort Studies; D055316:Cystatin C / Q000097:blood; D003971:Diastole; D018450:Disease Progression; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000503:physiopathology*; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D011674:Pulse; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000503:physiopathology*; D013599:Systole
chemical_list: C525030:CST3 protein, human; D055316:Cystatin C
keywords: blood pressure; cystatin C; diastolic blood pressure; elderly; hypertension; kidney function; systolic blood pressure.