Determining the association between the type of intervention for ischaemic heart disease and mortality and morbidity in patients with chronic kidney disease

Background Association between chronic kidney disease (CKD) and ischaemic heart disease (IHD) is well known. Clinically, because of the use of intra-arterial contrast, coronary angiograms are sometimes not performed to avoid further deterioration in kidney function among CKD patients. Aims To identify whether intervention for non-ST elevation myocardial infarction (NSTEMI) is associated with increased mortality or further renal deterioration. Methods A retrospective observational cohort study involving 144 patients with a diagnosis of IHD in the CKD.QLD registry from May 2011 to August 2017, with a minimum of 2-years follow up, was undertaken. Patients were divided into two groups based on whether they obtained an interventional or medical management for NSTEMI. Results Fifty-nine patients had medically managed and 85 patients had intervention for IHD. Patients in the medically managed group were observed to be significantly older (median: 78 vs 69 years; P < 0.05) with worse baseline renal function (median: 31 vs 36 mL/min/1.73 m(2); P <0.05) and higher serum urate level (median: 0.5 vs 0.4 mmol/L; P = 0.2). The interventional group had lower prevalence of diabetes, dyslipidaemia, cerebrovascular disease and peripheral vascular disease. Although this was not significant, Kaplan-Meier analysis revealed a significant decrease in mean survival of medically managed group compared with the interventional group. Furthermore, post adjustment for age and above comorbidities, the medically managed group and higher age were associated with significantly higher mortality. However, the patients in the medically managed and interventional groups had no significant difference in delta estimated glomerular filtration rate. Conclusions In this observational study, intervention for IHD was associated with increased survival with no change in renal disease progression in comparison with medically managed patients.