Effectiveness and Cost-Effectiveness of a Digital Care Pathway and Asynchronous Communication for Patients With Hypertension

Digital Care Pathway and Asynchronous Communication for Primary Care Patients With Uncontrolled Hypertension: a Cluster-Randomized Controlled Trial

The goal of this clinical trial is to learn if digital care pathway (DCP) and digital non-real-time messaging, in other words, asynchronous communication (AC) with nurse works to treat high blood pressure in adults in primary care. It will also learn if DCP and AC are good value for money. The main questions it aims to answer are:

• Does DCP and AC lower systolic blood pressure?
• Are DCP and AC good value for money in treating high blood pressure? Researchers will compare usual care plus DCP and usual care plus DCP with AC to usual care only to see if DCP and AC works to treat high blood pressure.

Participants will:

• Get usual care or usual care plus DCP or usual care plus DCP with AC for 6 months
• Visit the study nurse at the start of the trial and after 6 months for checkup and tests which include usual laboratory tests for high blood pressure
• Answer online survey questions and measure their blood pressure at home for 4 days at the start of the trial and after 6 months

The study will be conducted as a prospective, cluster-randomized controlled trial in six primary healthcare centres within the Wellbeing Services County of Pirkanmaa, Finland. Randomization will be performed at the healthcare centre level, with two centres allocated to each study arm. Because of the nature of the interventions, neither participants nor healthcare professionals can be blinded to treatment allocation.

Before the study begins, one induction session will be organised at all participating healthcare centres. This session will give healthcare professionals information about the study protocol and recommendations for hypertension management. In addition, professionals working at centres allocated to the intervention arms will receive training in the use of the digital care pathway and asynchronous communication.

One nurse from each participating centre will be appointed as a part-time study nurse. The study nurses will be responsible for participant recruitment, conducting baseline and follow-up visits, and promoting study awareness within their respective healthcare centres. During the study, participants will be monitored either by the study nurse or by other healthcare professional familiar with the participant. Hypertension management is optimised in accordance with the participant's home blood pressure readings.

Participants will be recruited for the study over a period of 6-12 months. Data will be collected at baseline and at the end of the 6 month follow-up. Data sources will include study nurse assessments during study visits, electronic health records and registers of the Wellbeing Services County of Pirkanmaa, the digital care pathway, and electronic questionnaires via the REDCap digital research platform.

Based on power calculations, assuming a statistical power of 80 percent and a two-sided significance level of 0.05, a minimum of 182 participants per study arm is required to detect a between-group difference of at least 5 mmHg in the change in systolic blood pressure during follow-up (SD of change in systolic blood pressure 17 mmHg). Considering cluster randomization and participant dropout during follow-up, the target sample size is 200 participants per study arm, resulting in a total sample size of 600 participants.

The results will be presented as means and standard deviations (SDs) for continuous variables, and frequencies and percentages for categorical variables. Between-group comparisons will be conducted using Student's t-test for normally distributed continuous variables, the Mann-Whitney U test for non-normally distributed continuous variables, and Pearson's chi-squared test or Fisher's exact test for categorical variables. The effects of the interventions on change in systolic blood pressure will be analysed using regression-based methods that account for the clustered study design, such as linear mixed-effects model. According to the intention-to-treat principle, all participants recruited to the study will be included in the primary analyses, regardless of whether they remained in the study for the entire follow-up period. A two-sided p-value of less than 0.05 will be considered statistically significant. All statistical analyses will be performed using IBM SPSS Statistics software.

The cost-effectiveness of the interventions will be assessed by calculating the incremental cost-effectiveness ratio (ICER), based on differences in both costs and effectiveness between the study arms. Costs will be assessed from the healthcare system perspective.

Inclusion Criteria:

• a diagnosis of hypertension for at least 3 months
• an office blood pressure of ≥140/90 mmHg at baseline
• access to a smartphone and the ability to use strong electronic identification for application login
• ability to measure home blood pressure
• ability to take care of the personal medication

Exclusion Criteria:

• unwillingness to participate in the study
• secondary hypertension or hypertensive crisis (office blood pressure >200/130 mmHg)
• atrial fibrillation
• stage 4 or 5 chronic kidney disease (eGFR <30 mL/min/1.73 m²)
• a life expectancy of less than 1 year
• pregnancy or breastfeeding
• a clearly impaired ability to use the study interventions or participate in the study, as determined by a healthcare professional (e.g., insufficient Finnish language proficiency, dementia, psychiatric illness, or sensory impairments)