Randomized Controlled Trial Testing the Efficacy of an mHealth Application to Reduce Risk Factors for the Primary Prevention of Stroke

BACKGROUND: We evaluated the efficacy of the Stroke Riskometer mobile phone application to change the Life’s Simple 7 risk factor score in a primary prevention population at 6 months postrandomization. METHODS: This phase III, prospective, outcome assessor–blinded, 2-arm randomized controlled trial in Australia and New Zealand recruited participants from August 2021 to January 2024. Inclusion criteria: age ≥35 and ≤75 years; ≥2 risk factors; smartphone ownership; and no cardiovascular disease history. The intervention group was given access to the application; the usual care group received one email with generic risk factor information. The primary outcome was the mean between-group difference in Life’s Simple 7 (score 0 [poor] to 14 [ideal], comprising blood pressure, cholesterol, glucose, body mass index, smoking, and physical activity and diet) from baseline to 6 months postrandomization. Secondary outcomes were between-group changes in individual Life’s Simple 7 items. Analyses were performed using intention-to-treat principles with ANCOVA and linear mixed models to examine differences between groups, with prespecified per-protocol and subgroup analyses. RESULTS: We randomized 862 participants (mean±SD age, 58±11 years; 63% women; 74% White). At 6 months postrandomization in intention-to-treat analyses, the mean difference between usual care (n=433) and intervention (n=429) groups in the change in Life’s Simple 7 score from baseline was 0.03 ([95% CI, −0.19 to 0.25]; P =0.788). Per-protocol analyses (n=320 usual care; n=276 intervention) were similar (mean difference in change, 0.20 [95% CI, −0.04 to 0.43]; P =0.106). Compared with usual care in intention-to-treat analyses, the intervention group had a nonsignificant increase in metabolic equivalent of task (metabolic equivalent of task) minutes per week of physical activity (313.42 [95% CI, −2.80 to 629.65]; P =0.052), with no differences in other Life’s Simple 7 items. CONCLUSIONS: Among a general population aged 35 years to 75 years with ≥2 stroke risk factors, there was no evidence that having access to the application changed overall Life’s Simple 7 scores at 6-month follow-up. Participants in the intervention group did have a nonsignificant increase in physical activity, compared with the usual care group, after 6 months, but not in other individual risk factors. REGISTRATION: URL: https://www.anzctr.org.au/ ; Unique identifier: ACTRN12621000211864.