Evidence of Impact and Effectiveness
Various models of hypertension TBC have been shown to increase the proportion of individuals with controlled blood pressure and to lead to a reduction in both systolic (SBP) and diastolic blood pressure (DBP), resulting in a strong recommendation for TBC approaches by the 2017 ACC/AHA blood pressure guidelines.5,21-25 There is great diversity in the types of hypertension treatment models studied, with few utilizing physician specialists and most utilizing nonphysician providers, such as community health workers, physician assistants, nurses, nurse practitioners, dietitians, social workers, and pharmacists.22,26-29 These professionals share duties of hypertension management with primary care physicians to reduce the burden of responsibility for care on any single provider type. TBC is patient-centered, and typically includes interprofessional collaboration, treatment algorithms, adherence counseling, frequent follow-up, home blood pressure monitoring, and patient self-management education.
Numerous studies have supported implementation of TBC in recent years. A systematic review and meta-analysis of 100 trials of hypertension TBC involving 55,920 patients concluded that the most effective blood pressure–lowering strategies use multilevel, multicomponent approaches to address barriers to hypertension control. Nonphysician providers are often involved in measuring blood pressure, ordering and assessing laboratory tests, and titrating medications.30 Compared with usual care, TBC with physician medication titration resulted in reductions in mean SBP and DBP (6.2 mm Hg and 2.7 mm Hg, respectively), while TBC with nonphysician medication titration also resulted in reductions in mean SBP and DBP (7.1 mm Hg and 3.1 mm Hg, respectively). Nurses and pharmacists are specifically mentioned by the 2017 ACC/AHA blood pressure guidelines as essential members of the hypertension treatment team.5 Randomized controlled trials (RCTs) and meta-analyses of TBC involving nurse or pharmacist interventions demonstrated greater reductions in SBP and/or greater attainment of blood pressure goals compared to usual care.21,26,31,32 The literature supports the roles of nurses and pharmacists in hypertension management in all aspects of care, including medication management, patient education and counseling, coordination of care and follow-up, population health management, and performance measurement with quality improvement.33
Nurses
Nurses are commonly part of TBC hypertension management programs. One meta-analysis and systematic review of international RCTs compared nurse, nurse prescriber (United Kingdom), and nurse practitioner interventions for hypertension with usual care. Interventions that included a stepped treatment algorithm and nurse prescribing showed greater reductions in SBP (8.2 mm Hg and 8.9 mm Hg, respectively) compared to usual care.31 Similarly, models that utilized telephone monitoring demonstrated greater achievement of blood pressure targets, while those that involved home monitoring showed significant reductions in blood pressure. Another international meta-analysis and systematic review of 11 nurse-led interventions in hypertensive patients with diabetes demonstrated a 5.8 mm Hg mean decrease in SBP compared to physician-led care. However, nurse-led care was not superior in achievement of study targets.34
A recent meta-analysis and systematic review, performed by Shaw and colleagues, sought to determine whether nurse-led protocols are effective for outpatient management of adults with diabetes, hypertension, and hyperlipidemia. All of the included studies involved a registered nurse who titrated medications by following a protocol, and most were RCTs comparing the nurse protocols to usual care. Overall, mean SBP and DBP decreased by 3.86 mm Hg and 1.56 mm Hg, respectively, while blood glucose and lipid levels were also reduced compared to usual care.24
Limited RCT data have been published since the Shaw et al meta-analysis. A single-blind RCT was performed in an urban community health care center in China among patients with uncontrolled blood pressure (SBP ≥ 140 mm Hg and/or DBP ≥ 90 mm Hg).35 The study group received care via a nurse-led model, which included a delivery design system, decision support, clinical information system, and self-management support, and the control group received usual care. At 12 weeks, patients in the study group had significantly lower blood pressure than control patients, with mean SBP/DBP reduction of 14.37/7.43 mm Hg and 5.10/2.69 mm Hg, respectively (P < 0.01). Improved medication adherence and increased patient satisfaction were other benefits of the nurse-led model.
Nurse case managers (NCM) also play a critical role in hypertension management, coordinating health care services to meet patient health needs. Ogedegbe sought to evaluate the comparative effectiveness of home blood pressure telemonitoring (HBPTM)+NCM versus HBPTM alone on SBP reduction in black and Hispanic stroke survivors.36,37 NCMs evaluated patient profiles, counseled patients on target lifestyle behaviors, and reviewed home blood pressure data. At 6 months, SBP declined by 13.63 mm Hg from baseline in the HBPTM+NCM group and 6.31 mm Hg in the HBPTM alone group (P < 0.0001). At 12 months, SBP in the HBPTM+NCM group declined by 14.76 mm Hg, while blood pressure in the HBPTM alone group declined by 5.53 mm Hg (P < 0.0001).
Pharmacists
Clinical pharmacists are also widely utilized in TBC models for hypertension management. Typical models involve pharmacists entering into collaborative practice agreements with physicians, leading to optimization of medications, avoidance of adverse drug events, and transitional care activities focusing on medication reconciliation and patient education in outpatient settings.30,38 The largest and most recent meta-analysis of pharmacist interventions, conducted in 2014 by Santschi et al,23 combined 2 previous systematic reviews to include a total of 39 RCTs with 14,224 patients.32,39 Pharmacist interventions included patient education, recommendations to physicians, and medication management. Compared with usual care, pharmacist interventions showed greater reductions in SBP (7.6 mm Hg) and DBP (3.9 mm Hg).23
Numerous studies substantiating the impact of pharmacist interventions on clinical outcomes have heavily influenced clinical practice and guideline development. Carter et al conducted a prospective, multi-state, cluster-randomized trial in 32 primary care clinics to evaluate whether clinics randomized to receive the pharmacist-physician collaborative care model (PPCCM) achieved better blood pressure outcomes versus clinics randomized to usual care.25 Investigators enrolled 625 patients with uncontrolled hypertension, 50% of whom had a prior diagnosis of diabetes mellitus or chronic kidney disease. The primary outcome of blood pressure control at 9 months in the intervention clinics compared to the control clinics was 43% and 34%, respectively (P = 0.059). The difference in mean SBP/DBP between the intervention and control clinics for all patients at 9 months was −6.1/−2.9 mm Hg. In a post-hoc analysis of patients with chronic kidney disease and diabetes, the pharmacist-intervention group had a significantly greater mean SBP reduction and higher blood pressure control rates compared to usual care at 9 months.40