Clinic Versus Ambulatory Blood Pressure in Resistant Hypertension: Impact of Antihypertensive Medication Nonadherence: A Post Hoc Analysis the DENERHTN Study.

Clinic-ambulatory blood pressure (BP) difference is influenced by patients- and device-related factors and inadequate clinic-BP measurement. We investigated whether nonadherence to antihypertensive medications may also influence this difference in a post hoc analysis of the DENERHTN trial (Renal Denervation for Hypertension). We pooled the data of 77 out of 106 evaluable patients with apparent resistant hypertension who received a standardized antihypertensive treatment and had both ambulatory BP and drug-screening results available at baseline after 1 month of standardized triple therapy and at 6 months on a median of 5 antihypertensive drugs. After drug assay samplings on study visits, patients took their antihypertensive treatment under supervision immediately after the start of the ambulatory BP recording, and supine clinic BP was measured 24 hours post-dosing; both allowed to calculate the clinic minus daytime ambulatory systolic BP (SBP) difference (clinic-SBP-day-SBP). A total of 29 (37.7%) were found nonadherent to medications at baseline and 38 (49.4%) at 6 months. At baseline, the mean clinic-SBP-day-SBP difference in the nonadherent group was 12.7 mm Hg (95% CI, 7.8-17.7 mm Hg, P<0.001). In contrast, clinic SBP was almost identical to day-SBP in the adherent group (clinic-SBP-day-SBP difference, 0.1 mm Hg; 95% CI, -3.3 to 3.5 mm Hg; P=0.947). Similar observations were made at 6 months. Using receiver operating characteristics curves, we found that a 6 mm Hg cutoff of clinic-SBP-day-SBP difference had 67% sensitivity and 69% specificity to predict nonadherence to the triple therapy at baseline. In conclusion, a large clinic-SBP-day-SBP difference may help discriminating between adherence and nonadherence to treatment in patients with resistant hypertension. Clinical Trial Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT01570777.

Routine urinary detection of antihypertensive drugs for systematic evaluation of adherence to treatment in hypertensive patients.

BACKGROUND: Nonadherence to antihypertensive therapy is an important cause of poor blood pressure control. However, to date, few effective and accurate tools exist to routinely evaluate drug nonadherence. METHODS: In this observational study, performed under conditions of routine clinical practice, we included 174 patients (aged 67 ±â€Š11 years) with treated essential hypertension who attended the outpatient hypertension clinic of a university hospital. Adherence to antihypertensive treatment was measured by using ultraperformance liquid chromatography-tandem mass spectrometry in spot urine at the time of clinical appointment and blood pressure measurement. Patients were also asked to report their adherence using a validated questionnaire (four-item Morisky Medication Adherence Scale). RESULTS: The prevalence of directly measured nonadherence by urine drug detection was approximately 10%. Compared with adherent patients, those who did not adhere to their treatment (n = 15) had a higher number of antihypertensive pills and drugs (P = 0.02), cotreatment with cardiovascular drugs (P < 0.05), and total concurrent medications and pills (P < 0.01). After adjustment for age, SBP and DBP were higher in nonadherent than adherent group (SBP: 146 ±â€Š18 vs. 131 ±â€Š14, respectively, P < 0.01; and DBP: 77 ±â€Š15 vs. 73 ±â€Š9, respectively, P < 0.01). There was no significant association between four-item Morisky Medication Adherence Scale score and directly measured nonadherence. A longitudinal analysis, performed in a subpopulation of 105 patients after a median follow-up of 11 months, showed that the adherence status remained unchanged in 88% of patients. CONCLUSION: These results indicate a good adherence to antihypertensive drugs in patients attending the outpatient clinics of a university hospital. They suggest that urine detection of antihypertensive drugs by ultraperformance liquid chromatography-tandem mass spectrometry is an accurate and practical tool for directly monitoring adherence. This direct information is not overlapping with self-report questionnaire.

Drug adherence in hypertension: from methodological issues to cardiovascular outcomes.

: Adherence to treatment is now well recognized as a crucial key in the effectiveness of antihypertensive drugs; however, it is often overlooked in the management of hypertension because methodology to assess it is partly unreliable and limits its use in clinical practice. The available evidence suggests that nonadherence is highly prevalent in a chronic asymptomatic condition such as hypertension. It may undermine benefits expected from antihypertensive agents and therefore, may negatively impact cardiovascular, cerebrovascular and renal outcomes. In this review, we discuss the methodological issues related to the measurement of drug adherence in a research setting and clinical practice, the prevalence and the impact of drug nonadherence on blood pressure control and thus in apparent resistant hypertension, and on cardiovascular, cerebrovascular and renal outcomes.

Adherence to Antihypertensive Treatment and the Blood Pressure-Lowering Effects of Renal Denervation in the Renal Denervation for Hypertension (DENERHTN) Trial.

BACKGROUND: The DENERHTN trial (Renal Denervation for Hypertension) confirmed the blood pressure-lowering efficacy of renal denervation added to a standardized stepped-care antihypertensive treatment for resistant hypertension at 6 months. We report the influence of adherence to antihypertensive treatment on blood pressure control. METHODS: One hundred six patients with hypertension resistant to 4 weeks of treatment with indapamide 1.5 mg/d, ramipril 10 mg/d (or irbesartan 300 mg/d), and amlodipine 10 mg/d were randomly assigned to renal denervation plus standardized stepped-care antihypertensive treatment, or the same antihypertensive treatment alone. For standardized stepped-care antihypertensive treatment, spironolactone 25 mg/d, bisoprolol 10 mg/d, prazosin 5 mg/d, and rilmenidine 1 mg/d were sequentially added at monthly visits if home blood pressure was ≥135/85 mm Hg after randomization. We assessed adherence to antihypertensive treatment at 6 months by drug screening in urine/plasma samples from 85 patients. RESULTS: The numbers of fully adherent (20/40 versus 21/45), partially nonadherent (13/40 versus 20/45), or completely nonadherent patients (7/40 versus 4/45) to antihypertensive treatment were not different in the renal denervation and the control groups, respectively (P=0.3605). The difference in the change in daytime ambulatory systolic blood pressure from baseline to 6 months between the 2 groups was -6.7 mm Hg (P=0.0461) in fully adherent and -7.8 mm Hg (P=0.0996) in nonadherent (partially nonadherent plus completely nonadherent) patients. The between-patient variability of daytime ambulatory systolic blood pressure was greater for nonadherent than for fully adherent patients. CONCLUSIONS: In the DENERHTN trial, the prevalence of nonadherence to antihypertensive drugs at 6 months was high (≈50%) but not different in the renal denervation and control groups. Regardless of adherence to treatment, renal denervation plus standardized stepped-care antihypertensive treatment resulted in a greater decrease in blood pressure than standardized stepped-care antihypertensive treatment alone. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01570777.