This article is more than 5 years old. Information may no longer be current.
Many patients with resistant hypertension fail to take prescribed medications
During a trial that initially reviewed the effects of medication on participants with resistant hypertension who received renal denervation, researchers found that only one in five participants adheres to their medication regimen.
“People mistakenly thought to have resistant hypertension — which is high [BP] despite taking three or more medications — end up seeing specialists and undergoing extra tests because we don’t understand why they are so difficult to treat,” Peter Blankestijn, MD, PhD, professor of nephrology and hypertension at the University Medical Center Utrecht in the Netherlands, said in a press release.
The SYMPATHY trial, which took place in the Netherlands from May 2013 to January 2016, included adults with resistant hypertension, whose average daytime systolic BP was 135 mm Hg when using three or more BP-lowering medications. Participants received catheter-based renal denervation with usual care (n = 95; mean age, 62 years; 42.1% men) or usual care only (n = 44; mean age, 60 years; 29.5% men).
The primary outcome was a change in participants’ daytime systolic BP after 6-month follow-up, and the secondary outcomes included changes in office systolic BP.
The mean daytime systolic BP was 160 mm Hg (standard deviation [SD], 17), diastolic BP was 93 mm Hg (SD, 15) and office BP was 169 mm Hg systolic/96 mm Hg diastolic (SD, 25/16).
After 6 months, participants who received renal denervation experienced substantial declines for daytime systolic BP (mean difference, 2 mm Hg; 95% CI, –6.1 to 10.2), 24-hour systolic BP (mean difference, 1 mm Hg; 95% CI, –7.1 to 9.1) and office systolic BP (mean difference, –8.2 mm Hg; 95% CI, –17.1 to 0.7). Upon meta-analysis, it was determined that there was no significant advantage to renal denervation in lowering daytime systolic BP (–1.6 mm Hg; 95% CI, –4.32 to 1.11) compared with usual care.
Medication adherence at baseline and follow-up was inadequate. Researchers wrote that 80% of participants were poorly adherent or completely nonadherent. Adherence was constant in 54 participants, 29 in the renal denervation group. Medication adherence dropped from poor to nonadherent in 24 participants (31%).
Participants who were nonadherent to their medications at baseline and follow-up had the highest systolic BP.
Among those who had the same medication adherence at baseline and follow-up, the renal denervation group experienced reductions in BP: daytime systolic BP (3.3 mm Hg lower; 95% CI, –13.7 to 7.2), 24-hour systolic BP (4.7 mm Hg lower; 95% CI, –15.3 to 5.8) and office BP (14 mm Hg lower; 95% CI, –25.7 to –2.4).
According to the researchers, the pooled effect of the renal denervation procedure reduced participants’ office systolic BP but not significantly (–5.4 mm Hg; P = .27).
“BP was higher in participants with poor adherence,” Blankestijn and colleagues wrote. “Therefore, our data support the notion that poor medication adherence contributes to the condition of apparent resistant hypertension.”
In a related editorial, Hillel Sternlicht, MD, FASN, hypertension specialist at Lenox Hill Hospital in New York, and George L. Bakris, MD, director of the ASH Comprehensive Hypertension Center at University of Chicago Medicine and a member of the Cardiology Today Editorial Board, wrote: “This study, by assessing drug adherence using baseline spectrometry, further refines the criteria necessary to determine whether a patient’s elevated [BP] is indeed resistant to pharmacological therapy.” – by Darlene Dobkowski
Disclosure : Bakris reports receiving consultant fees from AbbVie, AstraZeneca, Bayer, Boehringer Ingelheim, Daiichi Sankyo, Eli Lilly, GlaxoSmithKline, Medtronic, Novartis and Takeda. Blankestijn reports receiving grants from Dutch Kidney Foundation, Medtronic and ZonMw; and personal fees from Medtronic. Sternlicht and the other researchers report no relevant financial disclosures.