Preventive electronic (e)-counselling has been shown to reduce cardiovascular risk factors. However, heterogeneity in outcomes is commonly reported due to differences in e-protocols. We incorporated key features of an established behavioural therapy, motivational interviewing, to help standardize e-counselling in order to reduce blood pressure in patients with hypertension.
Subjects (n = 387, mean age = 56 years, 59% female, 72% taking = 1 antihypertensive drug) were diagnosed with stage 1 or 2 hypertension. Subjects were randomized to a 4-month protocol of e-counselling (beta version of the "Blood Pressure Action Plan", Heart and Stroke Foundation of Canada) vs waitlist control (general e-information on heart-healthy living). Outcomes were systolic, diastolic, and pulse pressures, and total lipoprotein cholesterol after treatment.
Intention to treat analysis did not find a significant group difference in outcomes due to contamination across the 2 arms of this trial. However, per protocol analysis indicated that subjects receiving = 8 e-counselling messages (a priori therapeutic dose) vs 0 e-counselling messages (control) demonstrated greater reduction in systolic blood pressure (mean, -8.9 mm Hg; 95% confidence interval [CI], -11.5 to -6.4 vs -5.0 mm Hg; 95% CI, -6.7 to -3.3, P = 0.03), pulse pressure (-6.1 mm Hg; 95% CI, -8.1 to -4.1 vs -3.1 mm Hg; 95% CI, -4.3 to -1.8, P = 0.02) and total cholesterol (-0.24 mmol/L; 95% CI, -0.43 to -0.06 vs 0.05 mmol/L; 95% CI, -0.06 to 0.16, P = 0.03), but not diastolic blood pressure.
These findings support the merit of evaluating whether e-counselling can improve blood pressure control and reduce cardiovascular risk over the long-term.