Stricter blood pressure goals; beneficial in chronic kidney disease?

This study compared the effect of strict vs. conventional blood pressure control on clinical outcomes in patients with chronic kidney disease.

Hypertension (high blood pressure) is increasing in prevalence worldwide and is associated with heart diseases and stroke. Therefore many trials have sought to determine how aggressively to treat elevated blood pressure in order to decrease mortality (death) risk.

Chronic kidney disease is a condition characterized by a gradual loss of kidney function. Studies of this disease suggest that the association of blood pressure with clinical events in patients with chronic kidney disease is different from that in the general population. The implication is that strict blood pressure control may not be favorable in patients with chronic kidney disease, and it could even be harmful. The few trials that have examined different blood pressure treatment goals in patients with chronic kidney disease were unable to distinctly establish the benefit compared to the risk of stricter blood pressure control.

This study examined 77,765 patients. All patients had chronic kidney disease and uncontrolled hypertension (blood pressure that remains above goal in spite of simultaneous use of three different types of antihypertensive drug). Patients were classified into 2 groups related to the value of their systolic blood pressure (SBP; pressure when the heart is contracting) after treatment (follow-up blood pressure). The first group included 5,760 patients with follow-up SBP <120 mm Hg while the second group included 72,005 patients with follow-up SBP between 120-139 mm Hg.  

During an average follow up of 6 years a total of 19,517 patients died; 2,380 deaths occurred in the SBP <120 mm Hg group (41%) and 19,517 deaths occurred in the SBP 120-139 mm Hg group (27%).

Following analysis researchers concluded that the risk of death from any cause was significantly higher in the SBP <120 mm Hg group compared with the SBP 120-139 mm Hg group. Patients in the SBP <120 mm Hg group showed a 70% average increase in risk of death compared to patients in the SBP 120-139 mm Hg group.

This study concluded that in patients with chronic kidney disease and uncontrolled hypertension, lowering SBP to less than 120mmHg is associated with higher risk of death compared with a SBP of 120 to 139 mm Hg.