Long term benefits of the Risk Assessment and Management Programme for patients with hypertension (RAMP-HT) on HT-related Complications and Mortality – A Population-based Cohort Study in Hong Kong

Abstract

The problem: Total cardiovascular disease (CVD) risk management delivered by a structured, protocol-driven multi-disciplinary programme added onto usual primary care for patients with hypertension (HT) has been demonstrated to enhance blood pressure (BP) control after 12 months, and reduce CVD complications after 3 years of follow-up. Nevertheless, the long-term effects of such programme on CVD risk profiles and HT-related complications are unknown. This study aims to evaluate the 5-year effectiveness of the multi-disciplinary Risk Assessment and Management Programme (RAMP-HT) for HT patients in the public primary care setting in Hong Kong. The approach (design/methods): This population-based prospective cohort study included a total of 69,084 patients (i.e. 34,542 RAMP-HT participants and 34,542 propensity-score-matched HT patients receiving usual care in public primary care clinics in Hong Kong), who were aged > 18 years and without prior clinical diagnoses of any HT-related complications including CVD and end-stage renal disease (ESRD) between October 2011 and March 2013. The proportion of patients achieving BP target (<140/90mmHg) at 60-month between the RAMP-HT and usual care groups were compared by chi-square test. The effects of RAMP-HT on HT-related complications and all-cause mortality were evaluated using Cox proportional hazards regression with adjustments for patient’s characteristics at baseline. The number-needed-to-treat (NNT) for HT-related complications and all-cause mortality was calculated based on the absolute risk reduction at 60 months between groups. Findings: At baseline, patients in both the RAMP-HT and usual care cohorts had a mean age of 65 years; 55.9% were female. Their mean systolic and diastolic blood pressure (SBP and DBP) was 136mmHg and 77mmHg, respectively, and the proportion of patients achieving BP target in both groups was 59%. After a median follow-up of 59.5 months, 74% RAMP-HT participants achieved BP target, which was significantly higher than patients receiving usual care only (69%). Patients in RAMP-HT group had significant risk reductions in CVD (Hazard Ratio (HR): 0.620, P<0.001), ESRD (HR: 0.600, P<0.001) and all-cause mortality (HR: 0.485, P<0.001) compared to the usual care group. The NNT for CVD, ESRD and all-cause mortality were 22, 147 and 22 respectively, indicating that for every 22, 147 and 22 patients enrolled in the RAMP-HT, one CVD, ESRD or all-cause mortality could be prevented, respectively. Consequences: The structured, protocol-driven multi-disciplinary RAMP-HT was demonstrated to confer sustained additional clinical benefits for HT patients over usual primary care in terms of greater reductions in HT-related complications and all-caused mortality. These remarkable findings support RAMP-HT as an integral and important component of usual HT care in primary care setting. Further study is warranted to investigate whether RAMP-HT is cost-effective and to explore its impact on healthcare burden.