Abstract 4144492: Association of the Intermountain Risk Score with Major Adverse Cardiovascular Events in Patients Assessed for Renal Transplantation

Background: In patients with end-stage kidney disease, assessment of cardiovascular (CV) risk is difficult due to a lack of analytical decision tools to guide care. The Intermountain risk score (IMRS) is a well-validated sex-specific risk prediction tool calculated from weightings of age and components of the complete blood count and basic metabolic profile that was originally derived to predict mortality. IMRS also predicts major CV events. This study evaluated the association of IMRS with major adverse CV events (MACE) in patients listed for renal transplantation (Tx). Methods: Patients evaluated for renal Tx between June 2015-April 2024 and subsequently listed were assessed using cardiac PET/CT, echocardiography, and other risk measures. MACE was defined as pre-Tx all-cause mortality, acute MI, or Tx de-listing. IMRS was computed using the 2009 1-year mortality approach and pre-defined sex-specific risk categories were used. Other data included demographics, comorbidities, CV risk factors, mode of dialysis, and a previously-derived 1-year PET risk score (using ischemic burden, coronary artery calcium, myocardial blood flow, transient ischemic dilation, smoking, obesity, diabetes and inpatient). Association with MACE-free survival was evaluated by Cox regression. Results: Among 691 patients with IMRS data (200 were missing labs for IMRS), age averaged 55.9±12.0 years (range 20.9-81.0 years) and 34.3% were female. MACE was found in 171 patients. IMRS was associated with MACE (Figure) in univariable analysis (high vs. low IMRS: HR=2.50, 95% CI: 1.44, 4.32, p=0.001; moderate vs. low: HR=1.55, CI: 0.99, 2.42, p=0.055). For high vs. low IMRS, females had HR=2.26 and males had HR=2.61. Analysis showed that 24.7% of the predictive ability of IMRS was explained by the PET risk score, MI and COPD history, and mode of dialysis. IMRS was independently associated with MACE when adjusted for those factors (high vs. low: HR=1.99, CI: 1.14, 3.49, p=0.016). Conclusions: IMRS was associated with long-term pre-Tx MACE outcomes in patients assessed for renal Tx. A quantitative tool computable from objective, standardized, and common electronic health record elements, IMRS may be useful alone as a low-cost, low-touch clinical decision tool to evaluate risk in early screening or together jointly as part of a more complete risk assessment with other factors such as the PET risk score, comorbidities, and dialysis data.