Optimal use of beta-blockers in high-risk hypertension: a guide to dosing equivalence

Comparison of Ratings of Perceived Exertion and Target Heart Rate-Based Exercise Prescription in Cardiac Rehabilitation: A RANDOMIZED CONTROLLED PILOT STUDY

PURPOSE

Although ratings of perceived exertion (RPE) are widely used to guide exercise intensity in cardiac rehabilitation (CR), it is unclear whether target heart rate ranges (THRRs) can be implemented in CR programs that predominantly use RPE and what impact this has on changes in exercise capacity.

METHODS

We conducted a three-group pilot randomized control trial (#NCT03925493) comparing RPE of 3-4 on the 10-point modified Borg scale, 60-80% of heart rate reserve (HRR) with heart rate (HR) monitored by telemetry, or 60-80% of HRR with a personal HR monitor (HRM) for high-fidelity adherence to THRR. Primary outcomes were protocol fidelity and feasibility. Secondary outcomes included exercise HR, RPE, and changes in functional exercise capacity.

RESULTS

Of 48 participants randomized, four patients dropped out, 20 stopped prematurely (COVID-19 pandemic), and 24 completed the protocol. Adherence to THRR was high regardless of HRM, and patients attended a median (IQR) of 33 (23, 36) sessions with no difference between groups. After randomization, HR increased by 1 ± 6, 6 ± 5, and 10 ± 9 bpm ( P = .02); RPE (average score 3.0 ± 0.05) was unchanged, and functional exercise capacity increased by 1.0 ± 1.0, 1.9 ± 1.5, 2.0 ± 1.3 workload METs (effect size between groups, ηp2 = 0.11, P = .20) for the RPE, THRR, and THRR + HRM groups, respectively.

CONCLUSIONS

We successfully implemented THRR in an all-RPE CR program without needing an HRM. Patients randomized to THRR had higher exercise HR but similar RPE ratings. The THRR may be preferable to RPE in CR populations for cardiorespiratory fitness gains, but this needs confirmation in an adequately powered trial.

Long-Term Hemodynamic Effects After Carotid Artery Revascularization

Objective:

The baroreceptor at the carotid body plays an important role in hemodynamic autoregulation. Manipulation of the baroreceptor during carotid endarterectomy (CEA) or radial force from carotid artery angioplasty and/or stenting (CAS) may cause both intraoperative and postoperative hemodynamic instability. The purpose of this study is to evaluate the long-term effects of CEA and CAS on blood pressure (BP), heart rate (HR), and subsequent changes on antihypertensive medications.

Methods:

A retrospective chart review was performed to identify patients who underwent CEA or CAS between 2009 and 2015 at a single tertiary care institution. Baseline demographics and comorbidities were recorded. Operative details of the carotid artery endarterectomy and the use of balloon angioplasty during the CAS were analyzed. Hemodynamic parameters such as BP, HR, and antihypertensive medication requirement were evaluated at 3, 6, 12, 24, and 36 months.

Results:

A total of 289 patients were identified. The average age was 70.6 years old, and males constituted 64.0%. All patients had moderate (>50%) to severe (>70%) carotid stenosis. Of those, 111 (40.5%) patients were symptomatic. Systolic BP (mm Hg) of CAS and CEA were similar over the entire follow-up period. Heart rate (beats/min) remained stable postoperatively. A reduced number of antihypertensive medications was observed in the CAS cohort during the first postoperative year when compared to the preoperative baseline: 2.03 at preop, 1.77 ( P < .01) at 3 months, 1.78 ( P = .02) at 6 months, 1.77 ( P = .02) at 12 months, 1.86 ( P = .09) at 24 months, and 2.03 ( P = =.50) at 36 months. Logistic regression analysis identified that CAS (odds ratio [OR]: 2.52, confidence interval [CI]: 1.09-5.83) and multiple (>2) antihypertensive medication use at baseline (OR: 5.89, CI: 2.62-13.26) were predictors for a reduction in the number of antihypertensive medications following carotid revascularization.

Conclusion:

Surgical intervention for carotid stenosis poses a risk of postoperative hemodynamic dysregulation. Although postoperative BP and HR remained relatively stable after both CAS and CEA, the number of postoperative antihypertensive medications was reduced in the CAS cohort for the first postoperative year when compared to baseline. Patients with multiple antihypertensive agents undergoing CAS should have close postoperative BP monitoring and should be monitored for a possible reduction in their antihypertensive medication regimen.

Migraine-preventive prescription patterns by physician specialty in ambulatory care settings in the United States

Many adults with migraine who require preventive therapy are often not prescribed the proper medications. The most likely reason is that primary care physicians are unacquainted with preventive medications for migraine. The present study assessed the migraine-preventive prescription patterns in office visits using data from the National Ambulatory Medical Care Survey from 2006 to 2009 in the United States. Patients who were 18 years or older and diagnosed with migraine were included in the analysis. In accordance with the recommendations of the headache guidelines, we included beta-blockers, antidepressants, triptans for short-term prevention of menstrual migraine, and other triptans for acute treatment. Weighted visits of adults with migraine prescribed with preventive medication ranged from 32.8% in 2006 to 38.6% in 2009. Visits to primary care physicians accounted for 72.6% of the analyzed adult migraine visits. Anticonvulsants (odds ratio [OR] 0.29, 95% confidence interval [CI] 0.14–0.57, p < 0.001) and triptans for menstrual migraine (OR 0.50, 95% CI 0.28–0.91, p = 0.025) were less frequently prescribed by primary care physicians compared with specialty care physicians, such as neurologists and psychiatrists. There were no significant differences in the prescription patterns of antidepressants and beta-blockers between primary and specialty care physicians. Beta-blockers were prescribed to patients with comorbidity of hypertension, and antidepressants were used by patients with comorbidity of depression. There are differences in the prescription patterns of certain type of preventive medications between primary care physicians and specialty care physicians.

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Anticonvulsants were less used by primary care physicians than specialty care physicians.

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Triptans for prevention were also less used by primary care physicians.

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No differences were found in patterns of antidepressants and beta-blockers.

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Beta-blockers were used for patients with comorbidity of hypertension.

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Antidepressants were used for patients with comorbidity of depression.

Associations of antiplatelet therapy and beta blockade with patient outcomes in atherosclerotic renovascular disease

Randomized trials have shown a neutral effect of percutaneous revascularization compared with optimal medical therapy in patients with atherosclerotic renovascular disease (ARVD). However, there are few data to define what constitutes optimal medical therapy. We present a retrospective analysis of 529 ARVD patients. Separate analyses were performed comparing outcomes in patients prescribed/not prescribed beta blocker and antiplatelet agents. Analyses were adjusted for effects of baseline covariates on probability of treatment and on clinical outcome. Over a median follow-up period of 3.8 years, antiplatelet therapy was associated with a reduced risk for death (relative risk, 0.52 [95% confidence interval {CI}: 0.31-0.89]; P = .02). Beta blocker therapy was associated with a reduced for death (relative risk, 0.45 [95% CI: 0.21-0.97]; P = .04) and nonfatal cardiovascular events (relative risk, 0.74 [95% CI: 0.60-0.90]; P = .003). Although limited by small patient numbers, this study suggests that in ARVD, treatment with antiplatelet therapy and beta blockade may associate with a prognostic benefit.

Antihypertensive drug class and adherence: an electronic monitoring study

BACKGROUND

Medication adherence is essential to optimizing blood pressure (BP) control. Prior research has demonstrated differences in pharmacy refill patterns according to antihypertensive drug class. No prior study has assessed the association between drug class and day-to-day adherence.

METHODS

Between 2011 and 2014, we enrolled a convenience sample of 149 patients with persistently uncontrolled hypertension from two inner-city clinics and concurrently measured adherence of up to four antihypertensive medications using electronic pillboxes during the interval between two primary care visits. The main outcome was mean percent of days adherent to each drug. Mixed effects regression analyses were used to assess the association between drug class and adherence adjusting for age, gender, race, ethnicity, education, health insurance, coronary artery disease, heart failure, chronic kidney disease, diabetes, number of medications, days monitored, and dosing frequency.

RESULTS

The mean age was 64 years; 72% women, 75% Hispanic, 88% prescribed ≥ 1 BP medication. In unadjusted analyses, adherence was lower for beta-blockers (70.9%) compared to angiotensin receptor blocking agents (75.0%, P = 0.11), diuretics (75.9%, P < 0.001), calcium channel blockers (77.6%, P < 0.001) and angiotensin-converting enzyme inhibitors (78.0%, P < 0.0001). In the adjusted analysis, only dosing frequency (P = 0.0001) but not drug class (P = 0.71) was associated with medication adherence.

CONCLUSIONS

Antihypertensive drug class was not associated with electronically measured adherence after accounting for dosing frequency amongst patients with uncontrolled hypertension. Low adherence to beta-blockers may have been due to the common practice of prescribing multiple daily dosing. Providers may consider using once daily formulations to optimize adherence and should assess adherence among all treated patients with uncontrolled hypertension.