Effect of Radiofrequency-Based Renal Denervation: The Impact of Unplanned Medication Change from a Systematic Review and Meta-Analysis

Background: Catheter-based renal denervation (RDN) has emerged as a promising treatment option for hypertension. However, randomized controlled trials (RCTs) have reported conflicting results on blood pressure (BP) reduction. Patient- and procedure-related confounders have been implied as the potential sources of inconsistent BP responses. We aimed to investigated whether unplanned and frequent medication changes in RDN studies affected the BP response to RDN by conducting sensitivity and subgroup analyses, according to antihypertensive medication change rates in a meta-analysis of RCTs.

Methods: We searched the PUBMED, EMBASE, and COCHRANE databases up to May 2018. RCTs that studied the effects of RDN on hypertensive patients were included. A meta-analysis was carried out using RevMan 5.3.

Results: A total of 12 studies were included, of which four fulfilled the inclusion criteria of < 10% medication change rate in our review. Subgroup meta-analyses of the four RCTs with < 10% medication change rates showed statistically significant reductions of 6.07 mmHg and 7.12 mmHg in 24-hour and office systolic BP, respectively. The 24-hour and office diastolic BP were also reduced (mean difference = -3.89 mmHg and -4.27 mmHg, respectively). These subgroup analyses had no heterogeneity (I² = 0%). In contrast, the pooled analysis of the 12 studies and the subgroup analysis of eight studies with > 10% medication change rates both had a high level of heterogeneity and no significant BP reduction.

Conclusions: The effectiveness of RDN was demonstrated across a broad range of antihypertensive medications used at baseline after removing the confounder of unplanned medication changes.