Effectiveness, Cost and Cost-effectiveness of the Risk Assessment and Management Programme for primary care patients with Hypertension

Abstract

Introduction: The Risk Assessment and Management Programme – Hypertension (RAMP-HT) was launched by the Hospital Authority (HA) to improve quality of hypertension (HT) management at all general out-patient clinics (GOPC) in Hong Kong since 2011. This study examined: 1. Effectiveness of the RAMP-HT in reducing adverse outcomes after 5 years; 2. Cost of the RAMP-HT; 3. Direct medical costs of primary care patients with hypertension; 4. 5-year cost-effectiveness of the RAMP-HT; 5. Lifetime cost-effectiveness of the RAMP-HT using simulation model. Methods: Population-based data were extracted from the HA Clinical Management System. 79,161 RAMP-HT participants were propensity-score-matched with same number of HT patients receiving usual GOPC care. Effects of RAMP-HT on cardiovascular diseases (CVD), end-stage renal disease (ESRD) and all-cause mortalities were evaluated using Cox proportional hazards regression. Programme cost of RAMP-HT was calculated based on setup and ongoing intervention costs collected from the HA and RAMP-HT clinics using costing questionnaires. Public medical cost of HT patients was estimated based on total public health service utilization. Cost-effectiveness of RAMP-HT per CVD, ESRD and all-cause mortality prevented, and event-free year gained were calculated as programme cost multiplied by the corresponding number-needed-to-treat. Lifetime cost effectiveness of RAMP-HT was estimated using Markov modelling. Transition probabilities of developing CVD and ESRD were estimated based on RAMP-HT participants versus usual care patients, and transitional probabilities of mortalities, health preferences and direct medical costs were based on HT patients with and without complications. Quality-adjusted life-years (QALY) was calculated by the life-year(s) gained by a patient multiplied by health preference assessed by Short-Form Six-Dimension (SF-6D). The incremental cost-effectiveness ratio (ICER) was calculated by the ratio of difference of direct medical cost to difference of QALY between RAMP-HT participants and usual care patients. Results: After a median follow-up period of 5.3 years, RAMP-HT participants had significantly lower cumulative incidence of CVD (9.1% vs. 15.0%), ESRD (0.9% vs. 1.6%) and all-cause mortality (5.0% vs. 11.0%) compared to patients receiving usual care. RAMP-HT participants also had 23-40% fewer hospitalization, A&E visits and SOPC attendances. The total cost of RAMP-HT was only HK$521 per participant over 5 years, but RAMP-HT resulted in an overall saving of HK$30,187 per participant. The cost invested on the RAMP-HT to gain 1 event-free-year were HK$1,905 for CVD, HK$3,395 for ESRD, and HK$3,490 for all-cause mortality. Assuming that the effectiveness of RAMP-HT would not decrease over time, each RAMP-HT participant could save HK$5,569 public healthcare cost over a lifetime. RAMP-HT was demonstrated to be cost-saving and dominated usual care service in managing HT patients. Conclusion: RAMP-HT is highly effective in reducing CVD, ESRD, all-cause mortality and public service utilization of HT patients in the busy naturalistic primary care setting in Hong Kong, and is projected to be cost-saving over lifetime. The RAMP-HT should be integrated routinely in primary care to reduce healthcare burden.