WIreless Monitoring and Financial Incentives for Uncontrolled HYpertension (WIFHY) Study

Hypertension is a major risk factor for cardiovascular morbidity and mortality. Despite the risks of hypertension and availability of effective treatment, a substantial number of patients have uncontrolled Blood Pressure (BP). Systematic reviews have shown that Home Blood Pressure Monitoring (HBPM) produces modest improvements in BP control and that HBPM yields greater benefits when combined with other interventions such as remote titration change or adherence-enhancing strategies.

The investigators propose a Wireless HBPM System comprising of a Wireless Home Blood Pressure Monitor and a Study Application that aims to: provide text messaging on BP advice and reminders on BP management based on BP readings; promote adherence to BP monitoring and adherence to medication; flag patients for counselling on medication adherence and remote titration (by doctor) during in-between visits; cut the response time in case of emergency; and skip polyclinic visits for well-managed patients.

An additional arm will include the the addition of modest financial incentives for participants when they monitor their BP. This arm is subdivided into two sub-arms (Instant Reward and Health Capital) where patients are eligible to receive the same incentive amounts but framed differently.

This study is novel in its comprehensive approach to patient disease self-management and remote provision of medical care, potentially reducing the burden on the health system and improving patient health outcomes.

Hypertension is a major risk factor for cardiovascular morbidity and mortality. The ultimate goal of hypertension treatment is to lower blood pressure (BP) and thereby reduce cardiovascular risk. Despite the risks of hypertension and availability of effective treatment, a substantial number of patients have uncontrolled BP. Systematic reviews have shown that Home Blood Pressure Monitoring (HBPM) produces modest improvements in BP control and that HBPM yields greater benefits when combined with other interventions such as remote titration change or adherence-enhancing strategies.

The effectiveness of HBPM is tempered because many patients with access to home BP monitors fail to regularly measure their BP or respond appropriately to high readings. New technology has made tele-monitoring of patient health feasible and has allowed for measurement and transmission of patient BP and other patient information from the home to a health care provider. An additional strategy to further improve the compliance of the patients with their hypertension management plan is to provide them with a clearer short term benefit, rewarding compliance. For example, those who achieve BP within the target range could receive a financial incentive.

The investigators' strategy to improve the effectiveness of HBPM to reduce BP is to use the full potential of wireless and mobile technology to create automatic feedback loops between the patient and the health care provider. The investigators propose a 6-month randomized controlled trial with 224 hypertensive patients with uncontrolled BP from the SingHealth Polyclinics in Bedok and Marine Parade, Singapore. The proposed trial will be a parallel study with one control arm and two intervention arms in ratio of 2:3:3 with the objective of measuring the incremental effectiveness and cost-effectiveness of an intervention with Wireless HBPM System, with and without financial incentives, compared to non-wireless HBPM alone.

Specifically, the investigators have the following primary aims and hypotheses:

A1: Determine whether a Wireless HBPM System with and without financial incentives is effective at reducing systolic blood pressure (SBP) compared to a non-wireless HBPM that relies on patient self-reporting and best practices (Usual Care, UC).

H1a: The average reduction in SBP at 6 months will be greater for the patients in the intervention arms (Wireless HBPM System with and without Incentives) compared to UC patients.

H1b: The average reduction in SBP at 6 months will be greater for the patients in the Wireless HBPM System with incentives arm compared to those in the Wireless HBPM System without incentives arm.

As well as the following secondary aims and hypotheses:

A2: Determine whether a Wireless HBPM System with and without financial incentives is effective at reducing diastolic blood pressure (DBP) compared to a non-wireless HBPM that relies on patient self-reporting and best practices (Usual Care, UC).

H2a: The average reduction in DBP at 6 months will be greater for the patients in the intervention arms (Wireless HBPM System with and without incentives) compared to UC patients.

H2b: The average reduction in DBP at 6 months will be greater for the patients in the Wireless HBPM System with incentives arm compared to those in the Wireless HBPM System without incentives arm.

A3: Quantify the incremental cost-effectiveness of Wireless HBPM System without incentives compared with UC, and of Wireless HBPM System with incentives compared to Wireless HBPM without Incentives.

H3a: The Incremental Cost-Effectiveness Ratio (ICER) of Wireless HBPM System without incentives compared to UC will be favorable relative to international benchmarks for cost-effectiveness analysis.

H3b: The ICER of Wireless HBPM System with incentives compared to Wireless HBPM System without incentives will be favorable relative to other published RCTs with primary aim of reducing SBP.

A4: Determine whether a Wireless HBPM System with and without financial incentives is effective at decreasing patient non-adherence to BP self-monitoring and hypertensive medicines compared to a non-wireless HBPM that relies on patient self-reporting and best practices (Usual Care, UC).

H4a, H4b: The average number of missing BP measurements (H4a) and percentage of medication doses not taken (H4b) during the last month of the study will be smaller for the patients in the intervention arms (Wireless HBPM System with and without incentives) compared to UC patients.

H4c, H4d: The average number of missing BP measurements (H4c) and percentage of medication doses not taken (H4d) during the last month of the study will be smaller for the patients in the Wireless HBPM System with incentives arm compared to those in the Wireless HBPM System without incentives arm.

A5: Determine whether financial incentives framed as health capital is effective at decreasing patient non-adherence to BP self-monitoring compared to financial incentives framed as a reward.

H5: The average number of missing BP measurements over the intervention period will be smaller for the patients in the Health Capital sub-arm compared to those in the Instant Reward sub-arm.

Eligibility Criteria:
Inclusion Criteria:

* Known hypertensive patients on at least one anti-hypertensive medication
* SBP more than or equal to 140 mmHg or DBP more than or equal to 90 mmHg for patients without diabetes, SBP more than or equal to 140 mmHg or DBP more than or equal to 85 mmHg for patients with diabetes, as verified by the average of the last 2 of 3 BP readings taken, on the day of polyclinic visit, at 3 minutes interval using the Omron HEM-7130
* Aged between 21 to 70 years of age;
* Singaporean citizens or Permanent Residents;
* Able to converse in English or Mandarin;
* Has a compatible smartphone (iOS Versions 8.0 and higher or Android Versions 5.0 and higher) with data plan or regular Wi-Fi access
* Ability to perform self-monitoring of BP as assessed by the CRC
* Expecting to be a patient of Bedok or Marine Parade Polyclinics for the duration of the trial

Exclusion Criteria:

* SBP equal or greater than 180mmHg or DBP equal or greater than 110mmHg, as verified by the average of the last 2 of 3 BP readings taken, on the day of polyclinic visit, at 3 minutes interval using the Omron HEM-7130
* pregnancy
* clinically unstable heart failure
* advanced kidney disease, i.e. eGFR \< 30 ml/min
* known liver disease
* Atrial Fibrillation
* underwent Double Mastectomy
* any other major debilitating disease or mental illness that precludes validity of informed consent or would result in the patient being unable to take their BP independently.
* started on angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin- receptor blockers (ARB) within the last 3 months
* on Warfarin or anti-coagulants (e.g. NOACs: Novel Oral Anticoagulants)
* known allergy to epoxy resin
* discharged from hospital within the last 3 months for complications related to hypertension
* newly referred to Specialist Outpatient Clinics (SOCs) or on follow-up for complications related to hypertension
* severe or overt macro albuminuria (urine ACR\>30mg/mmol or PCR\>0.5)
* confirmed glomerulonephritis
* living in a household where another member has been recruited into the trial