Allied health professional-led interventions for improving control of blood pressure in patients with hypertension

Abstract

Background Hypertension is a leading cause of mortality worldwide. The previous Cochrane review of interventions to improve control of hypertension suggested that allied health professional-led interventions might be effective. This review was undertaken to update and synthesise the evidence for such interventions. Objectives To review the evidence base for allied health professional-led interventions to improve the control of hypertension. To elucidate whether nurse or pharmacist prescribing is an important component of this complex intervention, and to identify areas in need of further study. Search methods We searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, Citations in Nursing and Allied Health Literature, theDatabase of Abstracts of Reviews of Effects and theNHS Economic EvaluationDatabase.We screened reference lists of all retrieved review articles to identify additional publications. We contacted experts in the field about other relevant trials or unpublished material, and identified relevant articles from personal archives. Selection criteria We included randomised trials that compared allied health professional-led interventions to usual care, if they reported outcome blood pressure or change from baseline, control of blood pressure to target, or proportions of patients taking anti-hypertensive medication. Data collection and analysis Two authors independently screened citations and full texts usingCovidence.These authors discussed disagreements and,where necessary, arbitration by a third author occurred. For included studies, one author extracted data and a second author checked extractions against the original paper.We resolved differences in interpretation by discussion, with arbitration froma third author if required.We contacted corresponding authors of retrieved studies to request missing data, clarify study details and enquire, where relevant, about unpublished studies. Main results We retrieved 3738 citations, reviewed 398 full texts and included 120 studies in meta-analyses. Mean reductions in blood pressure from baseline were 5.5/2.7mmHg (95% Confidence Interval 4.6 to 6.5/2.1 to 3.3) greater for interventions compared to usual care. Interventions were twice as likely (odds ratio (OR) 2.0 (1.8 to 2.4)) to achieve study blood pressure targets as usual care, and resulted in increased use of antihypertensive medication (OR 1.7 (1.4 to 2.1)). Interventions were generally effective across community, primary care, pharmacy and secondary care settings, and appeared equally effective for a wide range of participant ethnicities. Substitution of telephone support for face to face interventions did not appear to be effective. We found that the ability to recommend or prescribe changes inmedication, and undertaking at leastmonthly follow up until blood pressure targets are achieved, were factors associated with effective interventions. Adverse events associated with interventions were poorly reported. Costs of interventions were incompletely reported; most interventions cost more than usual care but no clear assessment of cost-effectiveness could be undertaken. There was some evidence to associate interventions with modest quality of life improvements. Authors’ conclusions Allied health professional-led interventions by nurses or pharmacists are more effective than usual care in lowering blood pressure, in achieving blood pressure targets, and in enhancing use of antihypertensivemedications. Effects are consistent across a range of clinical and community settings and applicable to a wide range of ethnicity. Effective interventions need face to face delivery, with at least monthly review until target blood pressure is achieved. The ability to change antihypertensive medications is a key component of successful interventions. We found no evidence of adverse events attributable to interventions, and some evidence for small improvements in physical well-being compared to usual care. Costs of interventions, where reported, exceeded those of usual care but cost effectiveness of interventions cannot be confirmed. Community health workers or outreach workers may also achieve improved blood pressure outcomes; little is known about implementation of nurse and pharmacist teams, therefore further study is required in these areas, and future trials should incorporate robust methods of cost-effectiveness assessment.