Abstract 3451: Reduced Glomerular Filtration Rate Independently Predicts the Diagnosis of Peripheral Arterial Disease and Extent of Coronary Artery Disease
5Impaired renal function is an important emerging risk factor for atherosclerosis. Whether this is independent of other cardiovascular risk factors is not clearly known. We aimed to assess whether renal impairment was independently associated with the degree of coronary and peripheral atherosclerosis.
Methods and Results One thousand and sixty seven subjects (mean ± standard deviation; age 66 ± 11 years, 63% male, 51% any history of smoking, 30% history of diabetes) undergoing elective coronary angiography for exertional chest pain and/or dyspnea were studied as part of the NHLBI funded Gene-PAD study. Angiograms were reviewed by an experienced angiographer, blinded to subject details. Significant CAD was defined as an epicardial stenosis of ≥70% in any vessel. PAD was defined as an ankle brachial index <0.9. Glomerular filtration rate (GFR) was estimated using the Modification of Diet in Renal Disease formula. Patients on dialysis or with acute infections, inflammatory and/or malignant disease were excluded. There was a 29% prevalence of PAD in subjects with GFR <60 mL/min/1.73 m2 and 16% if GFR was >60 mL/min/1.73 m2 (p <0.001 for difference). There was no difference in glucose, pack years smoking, BMI, lipids or c-reactive protein levels between subjects with GFR above or below 60 mL/min/1.73 m2. Reduced GFR was also predictive of a diagnosis of PAD [odds ratio (95%CI) =0.37 (0.17–0.83)}], independent of these other risk factors in logistic regression. Other predictors of PAD were increasing age, pack years smoking, fasting glucose and elevated triglycerides. Using ordinal regression, reduced GFR was an independent predictor of number of diseased coronary vessels (standardized coefficient −0.93, p =0.004). This was independent of age, gender, body mass index (BMI), lipids, blood pressure, pack years smoking and glucose. Other predictors in this model were age, male gender and lower high density lipoprotein cholesterol.
Conclusion Reduced GFR is associated with PAD and extent of CAD in a high risk group of subjects, independent of other risk factors. The mechanism for this association is unknown but does not appear to be explained simply by an excess of risk factors. Estimating GFR may be of value evaluating patients at highest risk of PAD and multivessel CAD.