Kidney Function and Progression of Carotid Intima-Media Thickness in a Community Study
Received 15 June 2007; accepted 28 November 2007. published online 04 March 2008.
Background
Limited data exist regarding the relationship between decreased kidney function, carotid intima-media thickness (IMT) progression, and vascular events.
Study Design
A community-based cohort study.
Setting & Participants
3,364 participants in the Intervention Project on Cerebrovascular Diseases and Dementia in the Community of Ebersberg, Bavaria Study.
Predictor
Quartiles of kidney function level estimated by means of creatinine clearance (Ccr) using the Cockcroft-Gault equation (Ccr <64, 64 to 75, 75 to 89, and >89 mL/min/1.73 m2).
Outcomes & Measurements
Change in carotid IMT during 2 years. Composite clinical study end point is the occurrence of major adverse cardiovascular events, a composite of myocardial infarction, stroke, and vascular death after 2 years.
Results
Baseline mean carotid IMT was 0.79 ± 0.19 (SD) mm. Mean change in carotid IMT was 0.02 ± 0.11 mm/y. Lower Ccr quartile at baseline was associated with a greater change in adjusted mean values: 0.024 (95% confidence interval [CI], 0.020 to 0.027); 0.019 (95% CI, 0.015 to 0.023); 0.012 (95% CI, 0.009 to 0.016); and 0.0077 (95% CI, 0.005 to 0.011), respectively (P < 0.01). After evaluation of change in carotid IMT, 36 patients (1.1%) experienced a fatal and nonfatal vascular event. Subjects with baseline Ccr less than the median (75 mL/min/1.73 m2) and change in carotid IMT greater than the median (0.008 mm/y) had the worst prognosis (log-rank test, P = 0.04). By means of multivariable analysis with the Cox proportional hazard model, lower baseline Ccr (hazard ratio, 1.04; 95% CI, 1.02 to 1.23; P = 0.03 per 1-mL/min/1.73 m2 decrease) and faster change in carotid IMT (hazard ratio, 1.15; 95% CI, 1.11 to 1.93; P = 0.01 per 0.1-mm increase) were associated with fatal and nonfatal vascular events.
Limitations
Microalbuminuria, associated with carotid atherosclerosis, was not available.
Conclusion
Decreased kidney function is associated strongly with faster change in carotid IMT. In addition, decreased kidney function and faster change in carotid IMT are associated with cardiovascular events.
4Department of Neurology, Technical University of Munich, Munich, Germany.
Address correspondence to Michel Chonchol, MD, University of Colorado Health Sciences Center, Division of Renal Diseases and Hypertension, Box C-281, Denver, CO 80262.
ABSTRACT