Mild renal impairment is associated with increased cardiovascular events and all-cause mortality following cancer diagnosis

Background The association between mildly decreased renal function and cardiovascular (CV) outcomes in cancer patients remains unestablished. Aims We sought to explore this association in asymptomatic self-referred healthy adults. Method We followed 25, 274 adults, aged 40-79 years, who were screened in preventive healthcare settings. Participants were free of CV disease or cancer at baseline. The estimated glomerular filtration rate (eGFR) was calculated according to the CKD Epidemiology Collaboration equation and categorized into groups [≤59, 60-69, 70-79, 80-89, 90-99, ≥100 (ml/min/1.73 m²)]. The outcome included a composite of death, acute coronary syndrome, or stroke, examined using a Cox model with cancer as a time-dependent variable. Results Mean age at baseline was 50 ± 8 years and 7973 (32%) were women. During a median follow-up of 6 years (interquartile range: 3-11), 1879 (7.4%) participants were diagnosed with cancer, of them 504 (27%) develop the composite outcome and 82 (4%) presented with CV events. Multivariable time-dependent analysis showed an increased risk of 1.6, 1.4, and 1.8 for the composite outcome among individuals with eGFR of 90-99 [95% confidence interval (CI): 1.2-2.1 P = 0.01], 80-89 (95% CI: 1.1-1.9, P = 0.01) and 70-79 (95% CI: 1.4-2.3, P < 0.001), respectively. The association between eGFR and the composite outcome was modified by cancer with 2.7-2.9 greater risk among cancer patients with eGFR of 90-99 and 80-89 but not among individuals free from cancer (P_interaction< 0.001). Conclusion Patients with mild renal impairment are at high risk for CV events and all-cause mortality following cancer diagnosis. eGFR evaluation should be considered in the CV risk assessment of cancer patients.