In a recent article published in the Annals of Internal Medicine and based on the results of the Systolic Blood Pressure Intervention Trial (SPRINT), patients at moderate cardiovascular risk who received more-intensive systolic blood pressure (SBP) treatment (target SBP, <120 mm Hg) had lower mortality (1.2% absolute difference at 3 years) than did patients who received less-intensive treatment (target SBP, <140 mm Hg). However, the incidence of new chronic kidney disease (CKD; i.e., ≥30% reduction in estimated glomerular filtration rate [eGFR] to <60 mL/minute/1.73 m2) was higher among intensively treated patients than among conservatively treated patients (NEJM JW Gen Med Dec 15 2015 and N Engl J Med2015; 373:2174). In a new analysis, researchers used a nested case-control design to evaluate urinary biomarkers of kidney damage at baseline and at 1 year in matched SPRINT patients with and without incident CKD.
Patients with incident CKD in the intensive group did not have elevations — and actually had some declines — in kidney damage urinary biomarkers during the first year of treatment. This finding suggests that a hemodynamic effect, rather than a true kidney damage effect, led to GFR-based diagnoses of CKD. Results were similar in subgroup analyses of patients who used angiotensin-converting enzyme (ACE) inhibitors or angiotensin-receptor blockers (ARBs) and those who did not.
The limitation of the study was that biomarker measurements were available only at baseline and 1 year.
The authors concluded that Incident CKD in the setting of intensive SBP lowering was accompanied by decreases, rather than elevations, in levels of kidney damage biomarkers and thus may reflect benign changes in renal blood flow rather than intrinsic injury.
Read full article here.
Source: NEJM Journal Watch
