Risk factor profile, incidence, and relevance of Mehran risk score to predict contrast-induced nephropathy in patients undergoing percutaneous coronary intervention

Abstract

Background: Contrast-induced nephropathy (CIN) is a grave but underdiagnosed complication of percutaneous coronary intervention (PCI) that is associated with increased in-hospital morbidity and mortality. Our aim was to study the incidence, risk factors of CIN, and applicability of Mehran risk score (MRS) in Indian population. Materials and Methods: A total number of 432 patients were enrolled in the study. Inclusion criteria were patients with acute coronary syndrome or chronic stable angina who underwent PCI. Baseline parameters of patients were noted and patients were followed for development of CIN. Results: The mean age of the study population was 57.2 + 10.43 years; males were 348 (80.6%) and females 84 (19.4%). Hypertension was present in 257 patients (59.5%), diabetes in 208 (48.1%), smoking in 208 (48.1%), anemia in 104 (24.1%), and heart failure in 95 (22%); the mean estimated glomerular filtration rate (eGFR) was 88.4 + 30.65 ml/min/1.73 m2 and the mean contrast volume usage was 122.8 + 41.9 ml. 64 patients (14.8%) developed CIN. On univariate analysis, age (P = 0.435), gender (0.125), hypertension (0.679), diabetes (0.177), and contrast volume (0.155) were not associated with the development of CIN, whereas smoking (0.021), hypotension (<0.001), heart failure (<0.001), anemia (0.001), and median eGFR (P < 0.001) were significantly associated with the development of CIN. However, on multivariate regression analysis, smoking was not associated with the development of CIN (P = 0.104). The incidence of CIN was 2.7-fold higher (odds ratio [OR]: 2.68, 95% confidence interval [CI]: 1.299–5.540, P= 0.008) in the intermediate group (MRS 6-10), 5.4-fold higher (OR: 5.403, 95% CI: 2.249–12.978, P < 0.001) in the high-risk group (MRS 11–15), and 51-fold higher (OR: 51.059, 95% CI: 18.195–143.278,P< 0.001) in the very high-risk groups (MRS >16) when compared to the low-risk group (MRS < 5). Dialysis was required only in 2 (3.1%) patients (P < 0.022). Conclusions: The overall incidence of CIN was 14.8%. The incidence of CIN in the very high-risk group (MRS >16) was substantially higher in our study (77.8%) as compared to the same group in Mehran study (57.3%).