Relationship Between Blood Pressure and Incident Chronic Kidney Disease in Hypertensive Patients

Background And Objectives: Hypertension is an important cause of chronic kidney disease (CKD). Identifying risk factors for progression to CKD in patients with normal kidney function and hypertension may help target therapies to slow or prevent decline of kidney function. Our objective was to identify risk factors for development of incident CKD and decline in estimated GFR (eGFR) in hypertensive patients.

Design, Setting, Participants, & Measurements: Cox proportional hazards models were used to assess the relationship between incident CKD (defined as eGFR <60 ml/min per 1.73 m(2)) and potential risk factors for CKD from a registry of hypertensive patients.

Results: Of 43,305 patients meeting the inclusion criteria, 12.1% (5236 patients) developed incident CKD. Diabetes was the strongest predictor of incident CKD (hazard ratio, 1.96; 95% confidence interval, 1.84 to 2.09) and was associated with the greatest rate of decline in eGFR (-2.2 ml/min per 1.73 m(2) per year). Time-varying systolic BP was associated with incident CKD with risk increasing above 120 mmHg; each 10-mmHg increase in baseline and time-varying systolic BP was associated with a 6% increase in the risk of developing CKD (hazard ratio, 1.06; 95% confidence interval, 1.04 to 1.08 for both). Time-weighted systolic BP was associated with a more rapid decline in eGFR of an additional 0.2 ml/min per 1.73 m(2) per year decline for every 10-mmHg increase in systolic BP.

Conclusions: We found that time-varying systolic BP was associated with incident CKD, with an increase in risk above a systolic BP of 120 mmHg among individuals with hypertension.