Cardiovascular Risk Factors Accelerate Kidney Function Decline in Post-Myocardial Infarction Patients: The Alpha Omega Cohort Study.

INTRODUCTION

Impaired kidney function is a robust risk factor for cardiovascular mortality. Age-related annual kidney function decline of 1.0 ml/min per 1.73 m after age 40 years is doubled in post-myocardial infarction (MI) patients.

METHODS

We investigated the impact of the number of cardiovascular risk factors (including unhealthy lifestyle) on annual kidney function decline, in 2426 post-MI patients (60-80 years) of the prospective Alpha Omega Cohort study. Glomerular filtration rate was estimated by serum cystatin C (eGFR) and combined creatinine-cystatin C (eGFR), using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations from 2012. Data were analyzed by multivariable linear and logistic regression.

RESULTS

At baseline, mean (SD) eGFR and eGFR were 81.5 (19.6) and 78.5 (18.7) ml/min per 1.73 m, respectively. Of all patients, 79% were men, 19% had diabetes, 56% had high blood pressure (≥140/90 mm Hg), 16% were current smokers, 56% had high serum low-density lipoprotein (LDL of ≥2.5 mmol/l), and 23% were obese (body mass index of ≥30.0 kg/m). After multivariable adjustment, the additional annual eGFR decline (95% confidence interval) was as follows: in patients with versus without diabetes, -0.90 (-1.23 to -0.57) ml/min per 1.73 m; in patients with high versus normal blood pressure, -0.50 (-0.76 to -0.24) ml/min per 1.73 m; in obese versus nonobese patients, -0.31 (-0.61 to 0.01) ml/min per 1.73 m; and in current smokers versus nonsmokers, -0.19 (-0.54 to 0.16) ml/min per 1.73 m. High LDL was not associated with accelerated eGFR decline. Similar results were obtained with eGFR.

CONCLUSION

In older, stable post-MI patients without cardiovascular risk factors, the annual kidney function decline was -0.90 (-1.16 to -0.65) ml/min per 1.73 m. In contrast, in post-MI patients with ≥3 cardiovascular risk factors, the annual kidney function decline was 2.5-fold faster, at -2.37 (-2.85 to -1.89) ml/min per 1.73 m.