Kidney Week

Abstract: FR-PO0270

Functional Capacity Is Impaired in Patients with Nondialysis-Dependent CKD and Obstructive Lung Disease

Session Information

• CKD: Omics, Systemic Stressors, and Targeted Pharmacotherapy
  October 23, 2026 | Location: Exhibit Hall A, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: CKD (Non-Dialysis)

• 2201 CKD (Non-Dialysis): Epidemiology, Risk Factors, and Prevention

Authors

• Giourdas, Ashley Danielle, Indiana University School of Medicine, Indianapolis, Indiana, United States

Ashley Danielle Giourdas, PhD

• Groninger, Nolan, Indiana University School of Medicine, Indianapolis, Indiana, United States

Nolan Groninger, MPH

• Narayanan, Gayatri, Indiana University School of Medicine, Indianapolis, Indiana, United States

Gayatri Narayanan, MS

• Campos, Monique Opuszcka, Indiana University School of Medicine, Indianapolis, Indiana, United States

Monique Opuszcka Campos, PhD

• Lim, Kenneth, Indiana University School of Medicine, Indianapolis, Indiana, United States

Kenneth Lim, MD, PhD, FASN

Background

Patients with chronic kidney disease (CKD) carry a higher risk and prevalence of obstructive lung disease. As CKD progresses, functional capacity measured by oxygen uptake at peak exercise (VO₂Peak), a predictor of mortality, declines. However, it is unclear to what extent the presence of obstructive lung disease impacts functional capacity in patients with CKD.

Methods

We analyzed data from the Cardiorespiratory Fitness in Individuals with Chronic Kidney Disease in Indiana (FIT-INDY) cohort. Patients who underwent both pre-bronchodilator spirometry and cardiopulmonary exercise testing (CPET) were included in the analysis. Patients with CKD (n=111) were stratified by an FEV₁/FVC <0.70 (obstructive lung disease) or ≥0.70 (non-obstructive control group). Group comparisons were performed by t-test, Mann-Whitney U test, Chi-squared or Fishers exact test as appropriate. Data was adjusted by multiple linear regression. Associations were performed by Spearman’s correlation.

Results

Age (62 [58-72] y vs 59 [48-67] y), estimated glomerular filtration rate (51.8±25.5 mL/min/1.73m² vs 55.6±23.8 mL/min/1.73m²) were similar between patients with a FEV₁/FVC <0.70 and ≥0.70 (all p’s>0.05). Patients with a FEV₁/FVC <0.70 had a lower BMI (26.3 [22.9 - 30.3] kg/m² vs 30.0 [27.1 - 33.5] kg/m², and a higher prevalence of chronic obstructive pulmonary disease (65% vs 20%), and a history of smoking (71% vs 36%, all p’s < 0.05). Significantly, VO₂peak and oxygen uptake efficiency slope (OUES) were lower for patients with FEV₁/FVC <0.70 (VO₂Peak = 9.8 [7.7-11.6] ml/kg/min, OUES = 1055±307) than those with FEV₁/FVC ≥0.70 (VO₂peak = 12.7 [9.8-16.9] ml/kg/min, OUES = 1335±492, all p’s<0.01). VE/VCO₂ Slope was higher in patients with an FEV₁/FVC <0.70 (42.5 [35.4-45.3] vs 33.7 [29.5-38.8], p<0.01). Peak ventilation, respiratory rate, and tidal volume were not different between the groups (p>0.05). After adjustment for age and smoking status, VO₂Peak, VE/VCO₂, and OUES remained significantly altered, while peak tidal volume was lower in those with a FEV₁/FVC <0.70 (p<0.05). FEV₁/FVC was negatively associated with VE/VCO₂ (r=-0.22, p<0.05) but not VO₂Peak (r=0.19, p=0.05).

Conclusion

CKD patients with obstructive lung disease have worse functional capacity and ventilatory efficiency highlighting how air flow limitations and inefficient gas exchange contribute to exercise intolerance. Further studies are warranted.

Funding

• Other NIH Support