The impact of automated brief messages promoting lifestyle changes delivered via mobile devices to people with type 2 diabetes: a systematic literature review and meta-analysis of controlled trials

BACKGROUND Brief automated messages have the potential to support self-management in people with type 2 diabetes, but their effect compared with usual care is unclear. OBJECTIVES To examine the effectiveness of interventions to change lifestyle behavior delivered via automated brief messaging in patients with type 2 diabetes. METHODS A systematic literature review of controlled trials examined the impact of interventions, delivered by brief messaging and intended to promote lifestyle change in people with type 2 diabetes, on behavioral and clinical outcomes. Bibliographic databases searched included Medline, Embase, CINAHL, PsycINFO, and ISI WoK. Two reviewers independently screened citations. We extracted information on study risk of bias, setting (high versus lowand middle-income countries) and intervention characteristics (including use of theory and behavior change techniques). Outcome measures included acceptability of the interventions and their impact on: i) determinants of lifestyle behavior (knowledge about diabetes, selfefficacy, attitudes towards self-management), ii) lifestyle behavior (diet, physical activity) and, iii) clinical and patient-reported outcomes. Where possible, we pooled data using random-effects meta-analyses to obtain estimates of effect size of intervention compared to usual care. RESULTS We identified 15 trials (15 interventions). Most interventions were delivered via shortmessage-service text-messaging (n=12) and simultaneously targeted diet and physical activity (n=11). Nine interventions consisted of unidirectional messages, whereas six consisted of bidirectional messages, with patients receiving automated tailored feedback based on selfreported data. The acceptability of the interventions and their impact on lifestyle behavior and its determinants was examined in a low proportion of trials, with heterogeneous results being observed. In 13 trials (1155 patients) where data were available there was a difference in glycated hemoglobin of -0.53% (95%CI, –0.59% to -0.47%) between intervention groups compared to usual care. In five trials (406 patients) there was a non-significant difference in body mass index of -0.25 kg/m2 (95%CI, -1.02 to 0.52). Interventions based on unidirectional messages produced similar effects in the outcomes examined than those based on bidirectional messages. Interventions conducted in low- and middle- income countries showed a greater impact than those conducted in high-income countries. In general, trials were not free of bias and did not use explicit theory. CONCLUSIONS Automated brief messages strategies can improve health outcomes in people with type 2 diabetes. Larger, methodologically robust trials are needed to confirm these positive results