Family-based interventions for optimal blood pressure outcomes in adults: a cluster randomised controlled trial in India

BACKGROUND AND OBJECTIVES: Globally, hypertension is a prominent risk factor for disability and death. We assessed the effectiveness of a family-centred strategy for lowering blood pressure in high-risk families. METHODS: Engaging families as intervention units, we conducted an open-label, cluster randomised controlled trial (ClinicalTrials.gov NCT02771873). First-degree family members and spouses of those suffering from coronary heart disease (CHD) over the age of 18 were included in the trial. The chosen families were allocated in a ratio of 1 : 1 to the enhanced usual care and intervention arms. The interventions included cardiovascular disease risk screening, systematic lifestyle modifications, facilitating access to primary healthcare services, and ensuring self-care adherence through regular follow-up. We measured the blood pressure at baseline, 12 months, and 24 months using electronic devices. A generalised estimating equation model assessed the between-group population average variation in DBP and SBP levels. RESULTS: The trial involved 1671 participants (women = 1111, mean age = 40.8 years) from 750 families. At the 2-year follow-up, the attrition rate was 3%. The adjusted between-group population average differences in SBP and DBP were -5.23 mmHg, 95% confidence interval (95% CI) -7.01 to -3.47, P < 0.001, and -2.56 mmHg, 95% CI -3.63 to -1.49, P < 0.001, respectively. The odds of blood pressure ≥140/90 mmHg at 2-year follow-up was 25% lower in the intervention than the usual care arm (odds ratio 0.75, 95% CI 0.60-0.95, P = 0.017). CONCLUSION: Family-centred lifestyle interventions may yield significant public health benefits in maintaining optimal blood pressure in high-risk individuals.