428 Beyond echocardiography: VO2Peak detects the functional impact of diabetes in patients with CKD

Objectives/Goals: Diabetes mellitus (DM) increases cardiovascular (CV) mortality risk in chronic kidney disease (CKD). It is unknown if patients with CKD and DM have a greater risk of impaired CV functional capacity compared to those without DM. We investigated CV functional capacity alterations in CKD patients with and without DM using cardiopulmonary exercise testing (CPET). Methods/Study Population: We performed a cross-sectional study of data from the Cardiorespiratory Fitness in Individuals with CKD in Indiana (FIT-INDY) cohort. FIT-INDY is an ambulatory referral cohort consisting of patients within the Indiana University Health system. All individuals included in this analysis had been diagnosed with CKD and underwent CPET as part of their medical standard of care. CPET was used to assess peak oxygen uptake (VO₂Peak), the gold standard measure of CV functional capacity. Participants were stratified into two groups: CKD+DM (n=53) or CKD (n=63). Group comparisons were performed using a t-test, Mann–Whitney test, or Fisher’s exact test. Adjusted analyses were completed using multiple linear regression. Results/Anticipated Results: The CKD+DM group had a higher prevalence of males, higher body mass index, heart failure, use of beta-blockers, SGLT2 inhibitors, and GLP1-agonsits (all p’s < 0.05). Age, race, and estimated glomerular filtration rate were similar between groups (all p’s ≥ 0.05). CPET demonstrated greater CV functional impairment in the CKD+DM group for VO2Peak [CKD+DM = 11.5 ± 4.1 mL/kg/min, CKD = 14.4 ± 5.2 mL/kg/min], VO2AT [CKD+DM = 7.7 (6.2 - 9.4) mL/kg/min, CKD = 8.8 (7.1 -10.9) mL/kg/min], and peak HR [CKD+DM = 107 (91 - 123.2) bpm, CKD = 116 (99.2 - 131.2) bpm; all p’s < 0.05]. After adjusting for sex, left ventricular ejection fraction, and medications, significance remained for VO2Peak and VO2AT, but not peak HR. Echocardiography findings were similar between groups before and after adjusting (all p’s ≥ 0.05). Discussion/Significance of Impact: CPET revealed worse CV impairment in patients with coexisting CKD and diabetes that were not evident on resting echocardiographic assessment. These findings suggest that CPET could be utilized as a diagnostic tool to risk-stratify this patient population.