Home blood pressure monitoring

Our study investigates whether weekly telephone coaching on home blood pressure monitoring and medication adherence results in improved blood pressure control during a 6 month coaching period. Furthermore, we aim to determine whether home-titration of antihypertensive medications further increases this benefit, and whether these effects are sustained 6 months after the coaching period has ended.

Study Design

Hypertensive patients are randomly assigned to one of two groups:

1. 1)

   Control group: Patients receive weekly health coaching phone calls on home blood pressure monitoring, medication understanding, and medication adherence.

2. 2)

   Active group: Patients receive weekly health coaching phone calls on home blood pressure monitoring and medication understanding and adherence, as well as assistance with home-titration of their antihypertensive medications.

A passive control group, receiving usual care, will be evaluated by retrospective chart review upon the completion of the study.

Ethics

Ethical approval to conduct this study has been granted by the Committee on Human Research at the University of California, San Francisco (approval number H8-01).

Study population and site

All participants are low-income English, Spanish, Cantonese, or Vietnamese speaking patients who receive primary care at the Family Health Center in San Francisco General Hospital. The Family Health Center is a primary care clinic in a teaching hospital.

Inclusion criteria

Patients are eligible for the study if they have a documented blood pressure greater than or equal to 145/90 on two or more separate visits in the past year. SBP must be greater or equal to 145 or DBP greater or equal to 90 on both readings. The two readings can include an elevated reading taken on the day that the patient is enrolled. Eligible patients are not required to carry a diagnosis of hypertension or be prescribed antihypertensive medications at enrollment. Patients must speak Cantonese, English, Spanish, or Vietnamese.

Exclusion criteria

Patients are excluded from the study if they are less than 30 years of age, their most recent creatinine is greater than 1.5 mg/dl, they have class III or IV heart failure, their life expectancy is less than one year or they have reduced cognitive capacity as determined by the patient's PCP. Patients with reduced cognition are included in the study if they have a known caregiver, such as a family member, capable of assisting the patient with home blood pressure monitoring and medication titration, and speaking with the health coach each week.

Identification and recruitment of participants

San Francisco's Department of Public Health electronic patient registry was searched for patients that: (1) are assigned to a PCP at San Francisco General Hospital's Family Health Center, (2) have a diagnosis of hypertension, (3) are greater than or equal to thirty years of age, (4) have no documented serum creatinine reading greater than 1.5 mg/dl, and (5) speak Cantonese, English, Spanish, or Vietnamese.

PCPs are given the list of their screened patients and are asked to exclude patients whom they believed would be unable to monitor their blood pressure or follow medication titration instructions due to physical or cognitive disability, psychiatric illness, or other reasons.

Additionally, patients with elevated blood pressures in the clinic are screened and recruited. Clinic staff or PCPs alert the study's health coaches if any patient has a blood pressure greater than 145/90 measured during intake. Health coaches review the chart to see if the patient met the eligibility criteria, including a blood pressure greater than 145/90 on a separate visit in the previous year. If not referred directly by the PCP, the health coach approaches the patient's PCP to see if the patient was eligible in terms of cognitive ability and life expectancy.

Patient enrollment, training, and randomization

Eligible patients are approached by a language-concordant health coach at the time of their primary care appointment and interviewed to ensure that they: (1) plan to continue coming to the Family Health Center for the next year, (2) have a telephone, (3) are willing to check their blood pressure at least twice a week, and (4) are willing to learn how to change their blood pressure medicines from home if enrolled in the active group. If patients answer yes to all of the above, they are given IRB-approved informed consent for enrollment in the study.

Patients are given a home blood pressure monitor (Omron model HEM-711AC) and trained in its use. They are also given a calendar logbook in which to record their blood pressures and heart rates. In order to ensure comprehension, health coaches request that patients "teach back" the process of checking their blood pressure and recording the values in their logbook.