Association of chronic kidney disease with the spectrum of ankle brachial index the CHS (Cardiovascular Health Study).
OBJECTIVE
This study sought to determine the association of chronic kidney disease (CKD) with high ankle brachial index (ABI) measurement and to compare its strength with that of CKD with a low ABI.


BACKGROUND
CKD is an important risk factor for cardiovascular disease (CVD) events. A high ABI, a marker of lower extremity arterial stiffness, is associated with CVD events and mortality. The association between CKD and high ABI is unknown.


METHODS
The CHS (Cardiovascular Health Study) enrolled community-living people >65 years of age and measured kidney function and ABI. Glomerular filtration rate (GFR) was estimated using equations that incorporated either cystatin C or creatinine, and CKD was defined by estimated GFR <60 ml/min/1.73 m(2). The ABI was categorized as low (<0.90), low-normal (0.90 to 1.09), normal (1.10 to 1.40), and high (>1.40 or incompressible). Multinomial logistic regression was used to evaluate the associations of CKD with ABI categories.


RESULTS
Among 4,513 participants, 23% had CKD, 13% had a low ABI, and 3% had a high ABI. In models adjusted for age, sex, race, hypertension, diabetes, smoking, body mass index, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and C-reactive protein, cystatin C-based CKD was associated with both low ABI (relative risk [RR]: 2.0; 95% confidence interval [CI]: 1.6 to 2.5; p <0.001) and high ABI (RR: 1.6; 95% CI: 1.0 to 2.3; p = 0.03). Results were similar when CKD was defined by creatinine.


CONCLUSIONS
CKD is associated with both the high and the low extremes of ABI in community-living older people. Future studies should evaluate whether arterial stiffness is an important mechanism leading to CVD in people with CKD.
Ix
Joachim H
JH
Department of Medicine, University of California San Diego, USA. joeix@ucsd.edu
Katz
Ronit
R
De Boer
Ian H
IH
Kestenbaum
Brian R
BR
Allison
Matthew A
MA
Siscovick
David S
DS
Newman
Anne B
AB
Sarnak
Mark J
MJ
Shlipak
Michael G
MG
Criqui
Michael H
MH
D000368:Aged; D000369:Aged, 80 and over; D055109:Ankle Brachial Index; D002097:C-Reactive Protein / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000097:blood / Q000209:etiology* / Q000503:physiopathology; D002908:Chronic Disease; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007674:Kidney Diseases / Q000097:blood / Q000150:complications* / Q000503:physiopathology*; D008055:Lipids / Q000097:blood; D008297:Male; D012307:Risk Factors
D008055:Lipids; D002097:C-Reactive Protein