Chronic kidney disease is a key predictive factor for potential myocardial ischaemia and poor prognosis in asymptomatic patients with diabetes mellitus

Abstract

Some asymptomatic patients with diabetes mellitus (DM) have critical coronary artery disease (CAD), although the guidelines do not recommend aggressive screening for CAD in asymptomatic patients. Chronic kidney disease (CKD) is among the serious co-morbidities of severe systemic atherosclerosis. Thus, CKD may be associated with potential myocardial ischaemia. Therefore, the present study aimed to determine the impact of CKD on the incidence of silent myocardial ischaemia (SMI) and the long-term outcomes in asymptomatic patients with DM. This study investigated 461 consecutive patients with DM. All patients who were asymptomatic and self-sufficient in daily life underwent the ergometer exercise (ERG) test. Coronary angiography was performed if the stress test was positive, or if the patient did not achieve 90% of the target heart rate. The primary end point included major adverse cardiac and cerebrovascular events (MACCE) including death, non-fatal myocardial infarction and stroke. The median follow-up duration after study enrolment was 35 months for the entire cohort of 461 patients. Eighty-one patients were diagnosed with SMI. The estimated glomerular filtration rate was significantly lower in the SMI group (70.5 ± 23.8 vs. 81.8 ± 30.0 mL/min/1.73 m², P < 0.001). SMI occurred more frequently in patients with advanced CKD [27/103, (26.2%) in stages 3-5], whereas only 5/68 (7.3%) patients without CKD, 13/81 (16.0%) patients with stage 1 CKD and 36/209, (17.2%) in stage 2, had SMI. The Kaplan-Meier curves revealed that, patients with SMI had poor clinical outcomes (log-rank: P = 0.016). The incidence of MACCE (log-rank: P = 0.009) was higher in patients with severe CKD > stage 3a in the SMI subgroup. Urinary albumin (mg/gCr) was associated with MACCE in the SMI subgroup [HR 3.37, 95%CI (1.170-9.521), P = 0.025] after adjusting for age, sex, and conventional risk factors. SMI was more prevalent in patients with CKD and the incidence was proportional to the CKD stage in asymptomatic patients with DM. Those Patients with CKD and SMI exhibited poor clinical outcomes. CKD may be a key factor for the identification and management of SMI in asymptomatic patients with DM in routine clinical practice.Trial Registration: UMIN000038340.