The Effect of Pharmacist-Initiated Home Blood Pressure Monitoring on Blood Pressure Control in Women

Purpose:

To determine the impact of home blood pressure monitoring when used in addition to pharmacist care, compared to usual care, in women with blood pressure elevated above their target level.

Hypothesis:

Women patients utilizing home blood pressure monitors and providing blood pressure readings to their community pharmacists who then provides tailored education to the patient and therapy recommendations to the patient's prescribing clinician will result in greater improvements in blood pressure control. In comparison to usual care.

Justification:

• Women are a target population for blood pressure control. A majority of women in Canada are not achieving their target blood pressure for optimal health outcomes.
• Home blood pressure monitors have demonstrated benefit in supporting patients in reaching their blood pressure targets, although they are under utilized.
• Community pharmacist care also has demonstrated benefit in supporting patients in reaching their blood pressure targets.
• Community pharmacies are where patients can acquire a home blood pressure monitor.

Research Method and Procedures:

Randomized Controlled Trial - Study length is 24-weeks with a final follow-up at 52-weeks.

Study Setting: Community Pharmacies throughout Ontario, Canada. Pharmacies will be selected identified and selected based on their location, using definitions of urban and rural communities from Statistics Canada's Statistical Area Classifications, and their willingness to partake in the study itself and follow-up with participants. The study is aiming to recruit a 50:50 ratio of pharmacies from urban and rural communities.

Screening/Case Finding:

Pharmacists may identify potential participants for screening via the following methods:

• During their usual workflow in providing patient care.
• During a hypertension screening day at the pharmacy.
• Searching patient pharmacy profiles with the following medication classes: Antidiabetes, antiobesity, antianginals, antihypertensive, cholesterol-lowering, smoking cessation therapies, prenatal vitamins or commonly used antihypertensives used during pregnancy such as methyldopa or labetalol.
• Referral from another healthcare provider.

Recruitment:

Once screening is complete if the participant is eligible for participation they will be asked by the pharmacist to provide consent. Consent will be obtained electronically via the REDCap database management system. Once consent is obtained the participant will be enrolled in the study and randomized to one of the two groups using the REDCap randomization module.

Both Groups:

• Pharmacist will measure participants blood pressure in the pharmacy using a standardized method based on the technique described by Hypertension Canada.
• Each participating pharmacy will be provided with a BIOS BD270 Automated Office Blood Pressure Monitor.
• Data to be collected by the pharmacist and input by the participant at baseline and week-24 includes demographics, medical history, medications, social history and cardiovascular risk factors.
• Participants prescribing clinician will be informed about the participants enrolment in the study.

Intervention Group:

• AOBP readings in the pharmacy will be taken at baseline and week-24.
• Participants will be provided with a BIOS BD240 home blood pressure monitor. Participants will measure their blood pressure at home every four weeks for five four week periods - they will take two consecutive BP readings in the morning and in the evening for a period of 7-days as per the Hypertension Canada 7-day BP Protocol. Participants will upload their data into the REDCap database via digital links sent via text message or email.
• Pharmacist will review BP readings with the participant at baseline and every 4 weeks. They will also send the BP readings along with suggestions for therapy modification to the participants prescribing clinician.
• After 24-weeks care is returned to the prescribing clinician and no further pharmacist specific interventions will be provided. The primary study will be complete at this point.
• After 52-weeks the pharmacist will complete a final follow-up to assess ongoing use of home blood pressure monitor and if there had been any further interactions with the prescribing clinician. No further follow-ups in regards to the study will occur beyond this point.

Control Group:

• AOBP readings in the pharmacy will be taken at baseline, week-12 and week-24.
• Participants will not be provided with a home blood pressure monitor.
• Pharmacists will review BP readings with the participant at each follow up and they will send BP readings to the participants prescribing clinician. The pharmacist will provide no recommendations for therapy modification.
• After the week-24 follow up participants will be offered a BIOS BD240 home blood pressure monitor. They will also be offered the opportunity to crossover to the intervention group for the next 24-weeks. If the participant agrees to crossover they will receive the full intervention protocol with the exception of the final follow-up at week-52. If they decline to crossover care is returned to the prescribing clinician and no further pharmacist specific interventions will be provided. The primary study will be complete at this point. After 52-weeks the pharmacist will complete a final follow-up to assess ongoing use of home blood pressure monitor and if there had been any further interactions with the prescribing clinician. No further follow-ups in regards to the study will occur beyond this point.

Sample Size:

Calculated to be 320 participants to achieve 80% power. This assumes an estimated SD of 13.5 to detect a difference in change of AOBP Systolic Blood Pressure of 4.5mmHg. We have assumed a drop-out or loss to follow up rate of 15% which increases our sample size to 368 participants with 184 participants in each group.

Plan for Data Analysis:

Data will be collected in the RedCap Database. Data will be analyzed in conjunction with the ABSPOR Unit who is providing the support for data analysis, interpretation and data visualization.

Inclusion criteria

Patients will be included if they are female ≥18 years of age and meet one of the following criteria:

No established diagnosis and/or treatment for hypertension.

• Average of three AOBP readings at two pharmacy visits within a 2-week period:
• SBP ≥140 mmHg or DBP ≥90 mmHg
• SBP ≥130 mmHg or DBP ≥80 mmHg if they have diabetes

Established diagnosis or currently on treatment for hypertension.

• Average of three AOBP readings from one pharmacy visit:
• SBP ≥140mmHg or DBP ≥90mmHg
• SBP ≥130mmHg or DBP ≥80mmHg if they have diabetes

Exclusion criteria

• Male
• Having hypertensive urgency or emergency as determined on screening defined as (these patients will be referred to urgent care):
• Severe elevation of SBP >180mmHg and/or DBP >120mmHg
• Taking oral contraceptives
• Arm that <24cm (9.4") or an arm that is >43cm (17")
• Currently have, or are using a home blood pressure monitor
• No access to a smartphone or internet
• Unwilling or unable to participate or provide informed consent and sign the consent form
• If the patient is pregnant
• Participating or planning to participate in another research study or project