Background:Despite established knowledge on the importance of hypertension (HT) screening and treatment to control blood pressure, the majority of HT patients remain uncontrolled. There are many possible barriers causing this evidence-practice gap, but there is no systematic overview of studies assessing these barriers. This review aims to synthesize findings from the literature on the prevalence and importance of barriers to HT control using a theoretical framework. Methods:Electronic databases MEDLINE, EMBASE and Global Health were systematically searched up to August 2011 and experts in the field were contacted. Two reviewers independently selected eligible studies based on the following criteria: 1) subjects were patients with HT or at risk of HT, or health care providers (HCP) managing HT patients; 2) studies examining barriers, obstacles, or facilitators to HT screening, management, or control; 3) qualitative and quantitative studies. Two reviewers extracted data, including study methodological quality items, and labeled identified barriers by expanding on a theoretical framework for behaviour change. Clinical importance of barriers was assessed by means of association with HT treatment and BP control. Results:Seventeen qualitative studies (10 reporting patient barriers and 7 reporting HCP barriers) and 37 quantitative studies (24 reporting patient barriers, 9 reporting HCP barriers, and 4 reporting both HCP and patient barriers) met the inclusion criteria. Of these, 81% (n=44) were from high income countries. Most studies had methodology issues; most commonly was the bias in measuring barriers. Discrepancies were observed between results from qualitative and quantitative studies. In qualitative studies, environmental barriers, specifically availability of care barriers, were most commonly discussed among patient as well as HCP studies.
Results from quantitative studies suggest that among HCP knowledge barriers were most commonly reported (83% of the HCP population). Results for patient reported barriers were different: Intention barriers were the most common barriers to HT screening (reported by 17% of the population), lifestyle change (reported by 37% of the population), and HT treatment adherence (reported by 63% of the population). Knowledge was the most common barrier to overall BP control among patients (reported by 64% of the population). Medication related barriers, specifically side effects, appeared to have the largest effect on HT treatment adherence (HR: 1.91, 95%CI: 1.47-2.47).
Conclusions:Barriers to HT control as reported by HCP and patients are multifactorial and largely modifiable, but evidence is primarily from high income countries and not comparable among settings due to methodological limitations. A more systematic way of measuring barriers to HT management is necessary.