Reduced renal function is a predictor of a more severe initial presentation of coronary heart disease, a case-control study showed.

-Team@CMHF

• A declining estimated glomerular filtration rate (eGFR) was associated with an increasing likelihood of presenting with an acute myocardial infarction (MI) rather than stable exertional angina (P<0.001 for trend), according to Alan Go, MD, of Kaiser Permanente of Northern California in Oakland, and colleagues.
• In particular, patients who had an eGFR less than 45 mL/min/1.73 m2 were nearly four times as likely to present with an acute MI compared with those with normal renal function (OR 3.82, 95% CI 1.55 to 9.46
• Coronary atherosclerosis is a spectrum of disease, ranging from clinically stable plaques to vulnerable plaques susceptible to rupture and thrombosis.
• The initial expression of coronary heart disease is largely dependent on the stability of these atherosclerotic plaques,” Go and colleagues explained.
• The severity and stability of the initial presentation of coronary heart disease significantly influences clinical management and long-term cardiovascular outcomes they continued, adding that the study suggests that patients with chronic kidney disease may have distinct risk factors for plaque vulnerability.
• In this study — the ADVANCE (Atherosclerotic Disease, Vascular Function, and Genetic Epidemiology) study — the researchers enrolled 803 adult patients whose first clinical presentation of coronary heart disease was acute MI and 419 whose first presentation was stable exertional angina.
• All had a baseline eGFR of 130 mL/min/1.73 m2 or less.
• Average eGFR was significantly lower in patients with acute MI than in those with stable angina (78.2 versus 81.2 mL/min/1.73 m2, P=0.006).
• The percentage of patients with an eGFR less than 45 was greater among those with acute MI (4.1% versus 1.9%).
• After adjustment for numerous potential confounders, including sociodemographic, family history, lifestyle factors, systolic blood pressure, body mass index, cholesterol levels, and prior use of cardiovascular medications, there was a strong relationship between reduced renal function and greater odds of presenting with acute MI (P<0.001 for trend).
• Compared with an eGFR of 90 to 130, the odds ratios for presenting with acute MI versus stable angina were 1.36 (95% CI 0.99 to 1.86) for an eGFR of 60 to 89, 1.55 (95% CI 0.92 to 2.62) for an eGFR of 45 to 59, and 3.82 (95% CI 1.55 to 9.46) for an eGFR of less than 45.
• Results support the hypothesis that patients with chronic kidney disease appear to have a greater likelihood of more clinically unstable and severe disease,” the authors wrote.
• It also suggests that clinical efforts should be targeted to identify this high-risk population before incident symptoms of atherosclerosis occur and that we should aim to develop effective interventions and strategies to shift the expression of coronary heart disease from acute myocardial infarction to more stable presentations
• Go and colleagues acknowledged that the study was limited in that it could not be used to determine the mechanism underlying the relationship between renal dysfunction and clinically unstable coronary heart disease.
• Other limitations included possible misclassification of eGFR levels, the lack of data on aspirin use, possible residual confounding, and uncertain generalizability to other healthcare settings or to uninsured patients.

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