Blog entry by Meguid El Nahas
BLOG BY PROF PIERRE DELANAYE
Am J Nephrol. 2016;43(4):271-80. doi: 10.1159/000446122. Epub 2016 Apr 29.
Cardiovascular Outcomes in Action to Control Cardiovascular Risk in Diabetes: Impact of Blood Pressure Level and Presence of Kidney Disease.
Persons with chronic kidney disease (CKD) represent a population prone to cardiovascular disease (CVD) but vulnerable to adverse medication effects. We assessed the impact of intensive antihypertensive therapy on the cerebrovascular and other CVD outcomes in high-risk patients with type 2 diabetes and baseline CKD.
Using current guideline criteria, 1,726 (36.9%) of 4,678 participants in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) blood pressure (BP) arm had mild to moderate CKD (CKD1-3B) at baseline. Participants of this study were randomized to intensive (systolic <120 mm Hg) or standard (systolic <140 mm Hg) BP goals. Fatal and non-fatal stroke were pre-specified secondary outcomes of the ACCORD study.
Total cerebrovascular events were significantly higher in participants with baseline CKD (0.66%/year) compared with participants free of CKD (0.28%/year). A significantly higher rate of events was observed in CKD participants. Intensive antihypertensive therapy in participants without CKD at baseline resulted in a 55% significant reduction of any stroke (hazard ratio 0.447; 95% CI 0.227-0.880) and a 50% reduction of non-fatal stroke (hazard ratio 0.498; 95% CI 0.250-0.993). In participants with CKD at baseline, the occurrence of any stroke was reduced by 38% (hazard ratio 0.623; 95% CI 0.361-1.074) and non-fatal stroke by 36% (hazard ratio 0.642; 95% CI 0.361-1.142). Test for interaction was NS between the 2 groups. Changes in other CVD outcomes did not reach statistical significance.
These findings suggest that intensive antihypertensive therapy offers significant cerebrovascular protection in diabetic participants without CKD at baseline, but significant benefit to patients with CKD cannot be excluded.
Globally, this post-haoc analysis confirm the results of SPRINT even if the population here is only diabetic patients.
In a few words, the benefit of intensive antihypertensive therapy in such diabetics is significant for stroke in non-CKD patients...but not in CKD diabetic patients. The authors consider CKD stage 1 to 3b and it could be intresting to know the risk associated with different stagings.
Other results are not very surprising for nephrologists: higher CV risk (all causes) for CKD compared to non CKD (but the risk profile in CKD is also higher). Also, the low BP target (in intensive therapy arm) is obviously more difficult to reach in CKD patients. It is not known if more therapies are required in the CKD arm.
Because the potential AE with antihypertensive therapies (more frequent in CKD than in non CKD, as well) and the absence of clear benefit, we should be careful with the blood pressure targets in CKD patients.