Hypertension Intervention Nurse Telemedicine Study (HINTS)

Detailed

Description Background:

There are 65 million Americans and over 8.5 million veterans who have been diagnosed with hypertension; yet only 31% of all hypertensive patients have their blood pressure (BP) under effective control (<140/90 mm/Hg). Uncontrolled hypertension greatly increases the risk of cerebral vascular accidents, coronary artery disease, myocardial infarction, renal failure, congestive heart failure, and mortality. Despite the damaging impact of hypertension and the availability of well-defined therapies and widely accepted target values for BP, interventions to improve BP control have had limited success.

Objectives:

The study is one of the first to compare three interventions designed to improve BP control: a behavioral educational intervention, an evidence-based medication management intervention, and combined intervention for patients with poor BP control defined by home BP monitoring. The primary hypotheses are: 1) Patients who receive only the behavioral intervention will show improved rates of BP control as compared to the control group over 18 months of follow-up; 2) Patients who receive only the hypertension medication management intervention will show improved rates of BP control as compared to the control group over 18 months of follow-up; and, 3) Patients who receive the combined intervention will show higher rates of BP control as compared to all other patients over the 18 months of follow-up.

Methods:

A three-year randomized controlled trial among veterans with poor BP control testing three interventions in three VA primary care clinics is proposed to improve BP control. We will test these interventions using home BP monitoring in a four group design administered via the telephone: 1) control group - a group of hypertensive patients who receive usual care; 2) Nurse-administered tailored behavioral intervention previously tested (HSR&D grant IIR 20-034); 3) Nurse-administered medication management according to a hypertension decision support system that uses the VA's Computerized Medical Record System (VA HSR&D grant CPI 99275); 4) combination of the tailored behavioral and medication management interventions.

A random sample of hypertensive patients with poor BP control at baseline were consented and randomly allocated to one of four arms. The interventions will activate only when home BP monitoring indicates inadequate BP control. Patients assigned to the behavioral intervention will receive a tailored self-management intervention to promote adherence with medication, information on the risks of hypertension and health behaviors at periodic telephone contacts. Patients will receive feedback about their recent BP values, continuous patient education, and will be monitored and supported to enhance treatment adherence. Patients randomized to the medication management arm will have their hypertension regimen changed by a nurse using a hypertension decision support system developed and validated in the VA. Medication recommendations generated are based on JNC 7 and the VA's hypertension treatment guidelines and are also individualized to patients' comorbid illnesses, laboratory values, and other elements of patients' clinical status. Medication management will be based on home BP monitoring and delivered by telephone. The nurse is part of an extended primary care team and communicates changes to the patients' primary care providers via a study physician.

The primary outcome will be a dichotomous measure representing whether or not the patient's BP is in control: >140/90 mm/Hg (non-diabetic) and >130/80 mm/Hg (diabetics). Measures will be made at six-month intervals over 18 months (4 total measurements). We will model the outcome measures and evaluate the interventions using a mixed effects model for dichotomous outcomes.

Status:

Primary study enrollment began May 5, 2006 and was completed November 2007. We randomized 591 participants in the study. Baseline recruitment was completed in November 2007. Participants' completed the six month follow-up interviews in June 2008 and 12 month follow-up in December 2008. 18 month follow-up was completed June 2009.

Study was granted an extension to complete two goals: 1) investigate the sustainability of BP control after completion of intervention, and , 2) examine what aspects of the intervention worked or did not work using qualitative interviews.

Background/Rationale:

Despite the impact of hypertension and the availability of well-defined therapies and widely accepted target values for blood pressure (BP), interventions to improve BP control have had limited success.

Objectives:

The study is one of the first to compare three interventions designed to improve BP control: a behavioral educational intervention, an evidence-based medication management intervention, and combined intervention for patients with poor BP control defined by home BP monitoring. We received an 11 month extension to evaluate 3 key components of the study (sustainability of BP effects, qualitative evaluation of the intervention, evaluation of the supporting materials used to ensure literacy levels and cultural sensitivity.)

Methods:

A 4-arm randomized trial with 18-month follow-up. Patents were selected from primary care clinics at the Durham VA Medical Center. Of the eligible patients, 591 individuals were randomized to either usual care or one of three telephone-based intervention groups. The intervention phone calls were triggered based on home BP values transmitted via telemonitoring devices. Patients were instructed to take their BP three times a week and transmit to study team. Behavioral management involved promoting health behaviors. Medication management involved adjustment of hypertension medications by a study physician and nurse based on hypertension treatment guidelines. The primary outcome was changes in BP control measured at six-month intervals over 18 months. For the sustainability extension of the study, in additional to collection of BP values, we will use qualitative analysis to examine the audio interviews.

Status:

Sustainability phase recruitment began May 1, 2010 and ended on Aug 15, 2010. Analyses are continuing.