Electronic cigarettes: we need evidence, not opinions

Abstract

The DENERHTN trial (May 16, p 1957) reported that renal denervation was associated with a baseline-adjusted difference of –5·9 mm Hg in daytime ambulatory systolic blood pressure after 6 months in favour of interventional treatment. Surprisingly, and in stark contrast with the results from the Symplicity HTN-2 and HTN-3 trials, the blood pressure response with ambulatory blood pressure measure ments was as high as with offi ce blood pressure measurements. Specifi cally, in the Symplicity HTN-2 trial, offi ce blood pressure was reduced by 32/12 mm Hg and 24 h ambulatory blood pressure was reduced by only 11/7 mm Hg after 6 months with renal denervation, and in the Symplicity HTN-3 trial, systolic office blood pressure changed by 14·1 mm Hg and 24 h ambulatory systolic blood pressure by only 6·7 mm Hg after 6 months with renal denervation. Furthermore, despite the blood pressure diff erence between denervation and control groups, the amount of additional antihypertensive drugs added in standardised stepped care was not higher (as expected) in controls. What is the explanation for this discrepancy? Since fi ve patients who were randomly assigned to the renal denervation group were not included in the modified intention-to-treat analysis, baseline patient characteristics should have also been reported for the 48 remaining patients. The authors have to be applauded for adding a measure of adherence rates in their study in view of the very high rate of non-adherence in patients with treatment-resistant hypertension. Nevertheless, increases in adherence after renal denervation not detected by the eight-item Morisky Medication Adherence Scale score could still contribute to improved blood pressure control.