The prognostic value of kidney failure based on glomerular filtration rate in predicting long in-hospital outcomes in patients with unstable angina

Objectives: Numerous recent studies have emphasized the role of kidney failure in developing ischemic heart disease (IHD) and the resulting adverse consequences. The purpose of the present study was to quantitatively assess the effect of kidney failure based on glomerular filtration rate (GFR) in predicting clinical outcomes in patients with unstable angina (U/A). Methods: This retrospective cohort study included 129 patients with unstable angina with preserved left ventricular function. Serum creatinine levels were specified at the beginning of their admission. The GFR at admission time was determined based on the MDRD index. Based on the GFR value, patients were classified into two groups, i.e., normal GFR (>60) and decreased GFR (<60). Results: The frequency of one-month mortality in <60 GFR and >60 GFR was 3.2% and 0.0%, respectively. Furthermore, the prevalence of 6-month mortality in <60 GFR and >60 GFR was 8.1% and 0.0%, respectively. The frequency of readmission in <60 GFR and >60 GFR was 29% and 11%, respectively. Likewise, the frequency of revascularization through coronary artery bypass graft (CABG) or percutaneous coronary intervention (PCI) in <60 GFR and >60 GFR was 25.8% and 8.9%, respectively. According to the multivariate logistic regression model, <60 GFR increased the risk of 6-month mortality up to 0.2 times (probability ratio of 2.081, P-value of 0.023). Regarding readmission, <60 GFR increased the need for readmission up to 2.4 times (probability ratio of 2.433, P-value of 0.049). On the other hand, the risk of CABG or PCI recurrence following initial intervention was 2.8 times higher in patients with <60 GFR than in the >60 GFR group (probability ratio 2.882, p-value .03. Conclusions: The study revealed that <60 GFR compared to higher values ​​of GFR is associated with an increased risk of 6-month mortality, increased readmission, and increased revascularization in patients with unstable angina.