We have previously demonstrated that intervention with SMS (Short Message Service) sent once or twice weekly doubled effectiveness of blood pressure (BP) control, independently of SMS-intervention frequency. The aim of the presented analysis was assess factors that determine the effectiveness of SMS for mobile on the hypertension (HT) control.
Design and Methods:
2055 hypertensive patients, treated for at least 2 weeks with angiotensin II receptor blockers (as mono- or polytherapy), were randomized into two groups with different SMS frequency (once or twice weekly). Each SMS contained two modules: a) a reminder about medication, b) the information about life style modifications, self BP control and drug adherence. In per protocol analysis, we assessed BP changes, patients’ compliance and lifestyle alterations at 1, 3 and 6th month of SMS intervention in 1015 patients. Multiple stepwise regression analysis was used to describe determinants of BP decline.
Of 1015 hypertensive patients (mean age: 56 ± 10 years, baseline BP: 145 ± 19mmHg), 58% were female, 35% had controlled HT and 66% had BMI>25 kg/m2. At 6-months of follow-up, the BP reduction was similar in the two groups, and averaged 17 ± 16 mmHg for SBP (p < 0.001 vs. baseline) and 10 ± 11 mmHg for DBP (p < 0.001 vs. baseline). It was associated with an increase of patients’ compliance with pharmacotherapy, from 50% to 93%. Smoking cessation, increased physical activity, salt and fat reduction in diet were declared respectively by: 11%, 57%, 56%, and 58% patients of both groups. On average 1.9 ± 2.8 kg weight reduction was observed. In stepwise regression analysis, male, lower level of education, presence of coronary heart disease and multidrug therapy were factors related to BP reduction. Moreover, in those who stopped smoking and reduced body weight, BP reduction was more pronounced.
Once weekly SMS-intervention for six months significantly improved blood pressure control and patients’ compliance. These beneficial effects were more pronounced in high risk patients.