Introduction: Early uncontrolled studies reported large blood pressure reductions in subjects with resistant hypertension treated with renal denervation, however these results were not confirmed in several of the latest publications.
Aim: The aim of the current study was to evaluate the effectiveness of RDN in controlled studies comparing RDN to either a sham procedure or to medical therapy.
Method: Only controlled studies were included in the analysis. Both the unadjusted and control-adjusted BP changes were calculated.
Results: We identified 11 publications of which only 3 were double-blinded RCTs with a sham control, while 8 were open label studies where the control group was treated with medical therapy. Only 2 studies assessed adherence to medical therapy with robust methodologies. Office BP reduction (- 18/8 mmHg) significantly overestimated ABPM change (- 9/- 5 mmHg), with high heterogeneity between the included studies. When the treatment effect was adjusted for the BP change in the control group, BP changes became non significant (ABPM: - 1.8 for systolic BP [95% CI - 4.5 to 0.9] and - 0.6 for diastolic BP [95% CI - 2.3 to 1.2]). These results were confirmed when only the sham-controlled studies were analysed.
Conclusions: In spite of promising results in early reports, renal denervation fails to show superiority to a sham procedure or to medical therapy in recently published controlled studies. Lack of a sham control in most publications and heterogeneity in assessment of treatment adherence may account for part the variability reported in the studies. Renal denervation fails to show superiority to a sham procedure or to medical therapy in recently published controlled studies.
Keywords: Drug adherence; Hypertension; Invasive therapy; Meta-analysis; Renal denervation; Resistant hypertension.