Photo Credit: Mohammed Haneefa Nizamudeen

The following is a summary of “Kidney volume and risk of incident kidney outcomes,” published in the June 2024 issue of Nephrology by Wu et al.

Low total kidney volume (TKV) increases the risk of chronic kidney disease (CKD). 

Researchers conducted a prospective study investigating the nonlinear relationships, new cases, causation, and the added value of low TKV beyond traditional kidney health markers. 

They used a TKV, height-adjusted TKV, and body surface area-adjusted TKV (BSA-TKV) of 34,595 White British participants in the UK biobank to study TKV, height-adjusted TKV, and BSA-TKV. The Cox models assessed links to CKD, AKI, and cardiovascular events. Prognostic CKD thresholds were found using a modified Mazumdar method. Two-sample Mendelian randomization checked genetic links.

The results showed that after adjusting for eGFR and albuminuria, a 10mL lower TKV was linked to a 6% higher CKD risk (HR 1.06, 95% CI: 1.03 to 1.08, P=5.8 x 10^-6), but not AKI (HR 1.00, 95% CI: 0.98 to 1.02, P=0.66). Adding BSA-TKV or prognostic thresholds at 119 (10th percentile) and 145 mL/m² (50th percentile) improved CKD risk accuracy. Mendelian randomization showed a 10% higher CKD risk with a 10 mL lower genetically predicted TKV (OR 1.10, 95% CI: 1.06 to 1.14, P=1.3 x 10^-7), and a 2-fold CKD risk linked to a 7.88 mL lower TKV (95% CI: -9.81 to -5.95, P=1.2 x 10^-15). No TKV cardiovascular links were found. 

Investigators concluded that kidney volume predicted CKD risk independently of traditional factors like eGFR and albuminuria and found a two-way relationship between kidney volume and CKD through Mendelian randomization.

Source: journals.lww.com/jasn/abstract/9900/kidney_volume_and_risk_of_incident_kidney_outcomes.349.aspx