Determinants of decline of renal function in treated hypertensive patients: the Campania Salute Network.

Background: Hypertension is a leading cause of chronic kidney disease (CKD) and a decrease in glomerular filtration rate (GFR) is associated with a higher prevalence of hypertension and an increased proportion of suboptimal blood pressure (BP) control.

Methods: To investigate characteristics associated with GFR decline, we selected 4539 hypertensive patients from the Campania Salute Network (mean age 53 ± 11 years) with at least 3 years of follow-up (FU) and no more than Stage III CKD. GFR was calculated at baseline and at the last available visit using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. GFR decline was defined as a ≥30% decrease from initial GFR for patients in Stage III CKD or by a composite ≥30% decrease from baseline and a final value of <60 for those < with Stage III or higher CKD.

Results: At a mean FU of 7.5 years, 432 patients (10%) presented with GFR decline. Those patients were older, more likely to be diabetic, with lower GFR and ejection fraction, higher systolic and lower diastolic BP and higher left ventricular (LV) mass and relative wall thickness at baseline; during FU, patients with GFR decline exhibited higher systolic BP, took more drugs and developed more atrial fibrillation (all P < 0.02). The probability of GFR decline was independently associated with older age, prevalent diabetes, baseline lower GFR, higher systolic BP during FU, FU duration, increased LV mass and incident AF with no impact from antihypertensive and antiplatelet medications.

Conclusions: During antihypertensive therapy, kidney function declines in patients with initially lower GFR, increased LV mass and suboptimal BP control during FU.