Effectiveness of app-based interventions for glucose management, cardiometabolic and mental health, and related risk factors: an umbrella review with meta-analysis

Background: Non-communicable diseases are the leading cause of death globally. Smartphone apps can offer benefits for individuals, health-care professionals, and governments in the prevention and management of such conditions. We aimed to systematically evaluate the effectiveness of app-based interventions in improving the outcomes of non-communicable diseases and in modifying their metabolic and behavioural risk factors. Methods: For this umbrella review and meta-analysis, we searched eight databases (Embase, Epistemonikos, IEEE Xplore Digital Library, APA PsycInfo via Ovid, PubMed, Scopus, Web of Science Core Collection, and Cochrane Central Register of Controlled Trials) for systematic reviews with meta-analysis published between Jan 1, 2013, and Jan 10, 2024, with no restrictions by geographical location or language. Additional studies were located through citation chaining and searching of reference lists. Eligible studies reviewed randomised controlled trials or controlled studies focused on adults (aged ≥18 years) with or at risk of non-communicable diseases and the use of app-based interventions for managing or improving the outcomes of these diseases and related health and risk factors, both metabolic and behavioural. Two investigators (EK and MFV) used COVIDENCE software to screen abstracts and full texts and to subsequently extract data from eligible studies. In case of missing data, authors of the relevant articles were contacted for unreported data or additional details. Effect sizes were measured as the standardised mean difference (SMD) and were aggregated through meta-analyses. 95% CIs for each review were synthesised using a random-effects model and prediction intervals were based on a t distribution. When more than ten reviews were available, publication bias was assessed visually through the inspection of funnel plots and by Egger’s test; if bias was suspected, a trim-and-fill analysis was applied to estimate a revised effect size. The quality of the included reviews was evaluated with the AMSTAR 2 checklist, the certainty of evidence for each outcome was assessed using the GRADE framework and the Ioannidis criteria, and heterogeneity was measured by calculating I2 values. This study was registered with PROSPERO, CRD42023426735. Findings: Of 6951 unique records identified by our searches, 383 underwent full-text review and 78 systematic reviews with meta-analysis, covering 31 outcomes, were included in the study. These reviews covered 496 primary studies and involved a total of 177 373 participants. App-based interventions were found to be effective in lowering diastolic blood pressure (SMD −0·414 [95% CI −0·606 to −0·221], I2=93%), systolic blood pressure (−0·444 [−0·689 to −0·199], I2=96%), glycated haemoglobin (−0·587 [−0·715 to −0·460], I2=91%), fasting blood glucose concentration (−1·189 [−1·605 to −0·774], I2=93%), 2 h postprandial glucose concentration (−1·229 [−1·609 to −0·848], I2=95%), anxiety (−0·215 [−0·407 to −0·02