Background: Nonpharmacological interventions have been efficacious to control blood pressure (BP) in clinical trials, but their long-term effectiveness in clinical practice was still not documented.
Methods: This is a prospective cohort study of 825 patients who received repeated nonpharmacological recommendations to treat hypertension. The outcomes were BP change and rate of BP control by pattern of adherence (informed by the patients) to the recommendations to follow low-salt and low-calorie diets and to do physical activities.
Results: Patients were followed for 23.1 ± 8.4 months. Between group deltas of BP change in patients with and without adherence to the low-salt diet, adjusted for baseline BP, body mass index (BMI), age, and number of drugs in use, were 5.1 (95% confidence interval: 1.7-8.6) mm Hg for systolic (P = 0.003) and 2.1 (0.2-3.9) mmHg for diastolic BP (P = 0.02). For adherence to low-calorie diet, the deltas were 6.6 (2.9-10.2) mm Hg (P < 0.001) and 2.0 (0.1-3.9) mm Hg (P = 0.045). Adherence to physical activities was not associated with a BP-lowering effect. Relative risks for a fall of 10 mm Hg in systolic or 5 mm Hg in diastolic BP, with adjustment for confounding, were 0.69 (95% confidence interval: 0.55-0.87) for adherence to the low-salt diet, 0.83 (0.66-1.05) for low-calorie diet, and 0.99 (0.79-1.24) for exercise.
Conclusions: Adherence to low-salt and low-calorie diets is associated with clinically relevant long-term BP reduction and better hypertension control in a clinical setting.