Blood pressure treatment below the standard accepted level does not offer an additional benefit for renal function in patients with chronic kidney disease (CKD) without diabetes, according to researchers.
However, nonblack patients or those with higher levels of proteinuria (an abnormal amount of protein in the urine) might benefit from therapies that lower blood pressure.
The review study, “Association of Intensive Blood Pressure Control and Kidney Disease Progression in Nondiabetic Patients With Chronic Kidney Disease: A Systematic Review and Meta-analysis,” was published in JAMA Internal Medicine.
The development and progression of nondiabetic CKD are closely interrelated to hypertension, and controlling blood pressure (BP) can decrease the risk of decline in renal function and cardiovascular mortality. However, there is still a debate about the ideal blood pressure target for preventing kidney disease progression in nondiabetic CKD patients.
To understand whether blood pressure control provides better protection for patients with nondiabetic CKD, Wan-Chuan Tsai of Far Eastern Memorial Hospital in Taiwan and colleagues conducted a review of relevant published studies.
The researchers included in their analysis studies comparing the impact of intensive blood pressure (BP) control (less than 130/80 mm Hg) with standard BP control (less than 140/90 mm Hg) on major renal outcomes in patients with CKD without diabetes.
From the nine randomized clinical trials the researchers included in their analyses, which included 8,127 patients who were followed for an average of 3.3 years, intensive and standard blood pressure control provided similar effects.
Specifically, the studies showed that compared with standard BP control, intensive BP control did not show a significant difference on the annual rate of change in GFR (glomerular filtration rate). GFR is considered the optimal way to measure kidney function, and it can help determine the extent of CKD in an individual.
There were also no significant differences in doubling of serum creatinine level, a 50 percent reduction in GFR, composite renal outcome, or all-cause mortality. A rise in blood creatinine levels is observed only after significant loss of functioning nephrons (the functional units of the kidneys).
However, the researchers found that for nonblack patients and those with higher levels of proteinuria, there was a trend toward a lower risk of kidney disease progression when intensive blood pressure-lowering treatments were used.