Kidney Week

Abstract: FR-PO0267

Effects of Normal-Protein vs. Low-Protein Diet on Renal Functional Reserve in CKD Stages 3 and 4: A Randomised Controlled Trial

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

• Yadav, Varuna, Atal Bihari Vajpayee Institute of Medical Sciences & Dr Ram Manohar Lohia Hospital, New Delhi, DL, India

Varuna Yadav, MD, MBBS, DM

• Mahapatra, Himansu Sekhar, Atal Bihari Vajpayee Institute of Medical Sciences & Dr Ram Manohar Lohia Hospital, New Delhi, DL, India

Himansu Sekhar Mahapatra, MD

• Tripathi, Madhavi, All India Institute of Medical Sciences New Delhi, New Delhi, DL, India

Madhavi Tripathi, MBBS

• Pursnani, Lalit, Atal Bihari Vajpayee Institute of Medical Sciences & Dr Ram Manohar Lohia Hospital, New Delhi, DL, India

Lalit Pursnani, MD

• B, Muthu kumar, Atal Bihari Vajpayee Institute of Medical Sciences & Dr Ram Manohar Lohia Hospital, New Delhi, DL, India

Muthu kumar B, MD, MBBS

• M K, Hari Prasad, Atal Bihari Vajpayee Institute of Medical Sciences & Dr Ram Manohar Lohia Hospital, New Delhi, DL, India

Hari Prasad M K, MD, MBBS

• Dev, Vipin, Atal Bihari Vajpayee Institute of Medical Sciences & Dr Ram Manohar Lohia Hospital, New Delhi, DL, India

Vipin Dev, MD, MBBS

Background

Renal functional reserve (RFR), defined as the difference between peak and baseline glomerular filtration rate (GFR), reflects the adaptive capacity of the kidney. This study evaluated how normal protein diet (NPD) and low protein diet (LPD) affect changes in both relative (RFR_%) (as primary end point) and absolute (RFR_abs) RFR, as well as rate of GFR decline over six months in patients with CKD stages 3 and 4.

Methods

This six month, single centre, parallel group randomized controlled trial enrolled adults (>18 years) with stage 3 & 4 CKD. Assessments at baseline and six months included clinical and laboratory parameters, eGFR, creatinine clearance (CrCl) and two plasma technetium 99m Diethylenetriamine pentaacetic acid (^99mTc DTPA) method before and after a 1 g/kg oral vegetarian protein load to calculate RFR_% and RFR_abs . Patients were randomized to either a NPD (0.8 g/kg/day) or a LPD (0.6 g/kg/day). Dietary adherence monitored by recall, record and 24 hour urinary urea nitrogen every 3 months. All parameters were repeated at six months to compare RFR_%(primary end point), RFR_abs and eGFR changes.

Results

Of 135 patients (64 NPD, 71 LPD), there was significant increase in measured GFR after protein loading in both groups at baseline and at six months (p < 0.001). The primary endpoint was met: six month change in DTPA derived RFR% was significantly less negative in LPD (−1.34%, 95% CI −4.15 to +1.57) versus NPD (−5.06%, 95% CI −8.71 to −2.63; p = 0.0014). ANCOVA confirmed the group effect F(1,132)=21.73, p<0.001. eGFR change did not differ between groups (p>0.05). A modestly significant correlation was observed between ΔUACR and ΔRFR% (ρ = 0.17, p = 0.044).

Conclusion

RFR may be considered as a sensitive tool to assess dietary effects on renal function compared to eGFR alone.

Acknowledgment

Professor Venkateshan Sekhar, management consultant for helping in statistical analysis. Miss Deepshikha and Dr Laxman for helping in diet charts and follow up.

Funding

• Government Support – Non-U.S.