Study Design
Post-hoc latent class trajectory analysis from the Virta Health continuous care intervention (CCI) trial (NCT02519309). 248 CCI participants and 87 usual care controls with type 2 diabetes followed for 2+ years. Compared sustained nutritional ketosis (SNK) group vs. moderate/low/unknown ketosis groups vs. usual care. Subgroup analysis of 23 CCI participants with baseline CKD stage 3+.
Intervention
Continuous care intervention with nutritional ketosis (individualized very-low-carb diet targeting blood BHB >= 0.5 mmol/L) with remote physician and health coach support.
Key Results
eGFR (sustained ketosis): +3.38 mL/min/yr
Sustained nutritional ketosis (SNK) subgroup (n=17) showed eGFR slope of +3.38 mL/min/1.73 m2/year vs. -0.69 in usual care (between-group difference 4.06, p=0.01).
eGFR (all CCI): +0.91 vs -0.68/yr
Overall CCI group: +0.91 mL/min/1.73 m2/year (p=0.03). Usual care: -0.68 mL/min/1.73 m2/year. Between-group difference 1.59 (p=0.06).
Dose-Response: Ketosis level matters
SNK: +3.38, Moderate: +1.09, Low: +0.20, Unknown: +0.22, Usual care: -0.69 mL/min/yr. Higher sustained ketosis associated with greater eGFR improvement.
Context & Comparison
While this study is in diabetic CKD (not PKD specifically), it demonstrates that sustained nutritional ketosis preserves and improves kidney function. The dose-response relationship mirrors findings in ADPKD trials. Note: the SNK subgroup (n=17) is small; the overall CCI group result (+0.91) is more robust.
Significance
This post-hoc analysis from a non-PKD population shows that sustained ketosis is associated with improved kidney function. The sustained ketosis subgroup gained +3.38 mL/min/year in eGFR (vs. -0.69 in usual care). Among 23 participants with CKD stage 3+, mean eGFR improved from 49.9 to 64.7 at 2 years. The dose-response pattern supports a causal relationship, though the small subgroup sizes warrant cautious interpretation.