Blood pressure load associated with progressive kidney function decline in biopsy-proven atherosclerotic chronic kidney disease patients.

BACKGROUND

Hypertension is a major risk factor for the progression of chronic kidney disease (CKD). However, the impact of blood pressure (BP) load, especially when office BP is normal, remains unclear. Thus, we conducted a retrospective cohort study to elucidate the impact of elevated BP load in patients with biopsy-proven CKD, BP load elevation, and a normal office BP compared with normotensive patients with CKD but without BP load elevation and those with hypertension.

METHODS

We retrospectively analyzed patients with histologically confirmed atherosclerotic CKD who underwent kidney biopsy and 24-h ambulatory BP monitoring (ABPM). Patients were classified into normotension, isolated BP load elevation, and hypertension groups. The primary outcome was a ≥ 30% sustained decline in estimated glomerular filtration rate (eGFR) within 3 years.

RESULTS

A total of 57 patients were analyzed. The isolated BP load elevation and hypertension groups showed a significantly higher incidence of adverse kidney events than the normotension group (p < 0.01). After adjusting for confounding factors (age, sex, urinary protein, and Mayo Clinic Chronicity Score), the hazard for kidney outcomes remained significant in the isolated BP load elevation group (hazard ratio, 9.25; 95% confidence interval, 1.29-66.30).

CONCLUSIONS

Isolated BP load elevation is a significant risk factor for CKD progression even in patients with normal office BP. Normalization of BP load may be a potential therapeutic target in patients with CKD. Comprehensive BP assessment using 24-h ABPM is crucial for CKD management, as it reveals clinically important abnormalities that conventional measurements may not capture.