Telemonitoring of Uncontrolled Hypertension

1. Research Questions Previous studies demonstrated the feasibility of telemonitoring of blood pressure. However, several issues remain unaddressed. * Feasibility of telemonitoring within the South American context has never been tested. No attempt has ever been made in South America to assess adherence to antihypertensive drugs in primary care. * Telemonitoring of blood pressure will never make it to the routine clinical practice unless it can be proven that application of the technique results in faster and better blood pressure control compared with usual care including self-measurement of blood pressure at home. * Secondary endpoints must also include adverse events, a simple assessment of quality of life, adherence, a log of technical problems, and cost-effectiveness. 2. General Design ERNESTINA is a randomised parallel-group study, which will address the feasibility and potential benefits of telemonitoring of blood pressure at home. Eligible patients will be recruited at outpatient medical clinics. \- Screening period followed by stratification and randomisation: Screening involves checking inclusion and exclusion criteria, ruling out secondary hypertension remediable by specific treatment, and obtaining informed written consent as outlined in the Helsinki declaration. Eligible patients will be stratified by centre and randomised in a one-to-one proportion to control or intervention. Randomisation will be implemented by sequentially numbered sealed envelopes, which contain the group assignment. These envelopes will be available at the practices, so that no contact with the Studies Coordinating Centre (SCC) will be necessary to randomise the patient. \- Randomised period: Investigators will optimise medical treatment by rotating patients through different classes of antihypertensive drugs, combining drug classes according to the current guidelines of the Argentinian and European Societies of Hypertension (SAHA and ESH), while achieving the maximal tolerated dose of each drug. In the intervention group, investigators will receive a report on the telemonitoring data at weekly intervals; in the control group doctors will receive information on the self-measured blood pressure as recorded at home in the week preceding the office visit via a diary card. Doctors are free to schedule contacts with their patients and office visits at their own discretion but visits should be at least every 3 weeks. Once blood pressure control is achieved, the blood pressure measuring devices (telemonitoring enabled or not) will be recuperated and will become available for a next patient. In the control group, patients will keep a diary card in the week preceding the office visits. \- Late follow-up: Three months after achieving blood pressure control, all patients will be telemonitored for 1 week and complete a diary card, preceding an office visit. 3. Primary and Secondary Endpoints Primary endpoint The primary endpoint will be the time to blood pressure control in the two randomised groups. Blood pressure control will be defined as a self-measured blood pressure at home below 135 mm Hg systolic and 85 mm Hg diastolic. Blood pressure control is assumed to be present if the aforementioned levels are attained during the week preceding the last office visit of the randomised treatment visit. Treatment resistance is a home blood pressure not controlled on 3 drugs classes given at maximal doses, preferably including a diuretic after 6 months of follow-up. These patients might be referred for further exploration and treatment adjustment to a hypertension centre. Secondary endpoints Secondary endpoints related to blood pressure control (efficacy) are: * The proportion of patients reaching blood pressure control on self-measurement at home and office measurement; Blood pressure control on office measurement is a seated blood pressure below 140 mm Hg systolic and 90 mm Hg; * The proportion of patients reaching and maintaining blood pressure control on self-measurement and office measurement at the late follow-up visit; * The intensity of medical treatment; * Adverse events, recorded by a self-administered questionnaire. * Assessment of drug adherence; * Assessment of quality of life; * Analysis of cost-effectiveness. Economic Analysis The cost-effectiveness analysis will include both the direct and indirect costs of the intervention. The costs will be balanced against the use of medical resources, including visits, medications, and use of medical resources. Moreover, the incremental cost-effectiveness ratios (ICERs) will be calculated by dividing the net cost of intervention by the total incremental health care costs after the intervention according to the formula ICER = (Ci - Cc) / (Ei - Ec), where Ci and Cc and Ei and Ec are the costs and effectiveness associated with the intervention and usual care, respectively. Sensitivity analyses will examine the influence of uncertainty in the variables and assumptions. Model performance will be estimated through confidence intervals estimated in a probabilistic manner using Monte Carlo simulation.