Summary: In adults with type 1 or type 2 diabetes, a secondary analysis of the mySugr PRO randomised controlled trial (n=342) found that using a digital diabetes logbook roughly doubled the odds of reaching HbA1c 6.5% or below at three months (odds ratio 2.24, 95% CI 1.12 to 4.47; P=.02). Propensity-matched real-world data (n=2861) showed associated reductions in mean blood glucose at three and twelve months, largest among those with high baseline HbA1c. The design is observational and secondary, so these findings are associational rather than proof of efficacy.
PICO Summary
| Element | Detail |
|---|---|
| Population | Adults with type 1 or type 2 diabetes. RCT secondary-analysis cohort n=342; propensity-matched real-world cohort n=2861 (12-month subcohort n=1176). Conducted via the mySugr PRO programme (German Clinical Trials Register DRKS00022923). |
| Intervention | Use of the mySugr digital diabetes logbook app for self-monitoring and self-management. |
| Comparison | RCT control group not using the logbook (group allocation, baseline HbA1c as covariate). Real-world analyses used within-person change from baseline (single-sample t tests), with no concurrent untreated comparator. |
| Outcome | RCT: odds of HbA1c 6.5% or below at 3 months, OR 2.24 (95% CI 1.12 to 4.47; P=.02). Real-world mean blood glucose change at 3 months: type 1 -16.3 mg/dL (95% CI -20.6 to -12.4; P<.001); type 2 -27.3 mg/dL (95% CI -28.7 to -25.9; P<.001). Largest change in those with baseline HbA1c above 8.5% (type 1 -82.2 mg/dL; type 2 -104.6 mg/dL; both P<.001). Total cohort at 12 months -19.8 mg/dL (95% CI -21.8 to -17.9; P<.001). No absolute risk reduction, NNT, or adverse-event data reported. |
Digital diabetes logbook and glycaemic control
RCT secondary analysis · type 1 and type 2 diabetes · 3 months
Logbook use roughly doubled the odds of reaching HbA1c 6.5% or below at three months. The finding is from a secondary RCT endpoint with a wide confidence interval and manufacturer sponsorship, so it is hypothesis-supporting rather than proof of benefit.
Expert Commentary
This report should be read as hypothesis-supporting rather than practice-changing. The only controlled comparison is the secondary RCT endpoint, where logbook use was associated with roughly double the odds of reaching an HbA1c of 6.5% or below at three months. That odds ratio is statistically significant but its confidence interval is wide and reaches close to unity, so the effect is imprecise and rests on a single short-term threshold outcome. The much larger blood glucose reductions come from propensity-matched real-world data analysed with single-sample t tests, which lack a concurrent untreated comparator and therefore cannot separate the app from regression to the mean, secular trends, or the engagement of people who choose to use a logbook. The most important caveat is sponsorship: several authors are employed by the device manufacturer and by the company marketing it, and the study evaluates that company’s own product, which warrants caution about both effect size and framing. The very large reductions in those with the highest baseline HbA1c are biologically plausible but also exactly where regression to the mean is strongest. Can I use this with my patients? Not yet as evidence of benefit, though it is reasonable to offer a structured digital logbook to a motivated patient already inclined to self-monitor, while being honest that proof of glycaemic benefit is limited. An adequately powered, independently funded trial reporting HbA1c, adverse effects, and sustained engagement would settle the question.
References
Ehrmann D, Ruch B, Mitter M, Kober J, Hermanns N, Schäfer V, Kulzer B, Silbermann S. Improvements in Glycemic Control With a Digital Diabetes Logbook: Secondary Analysis of a Randomized Controlled Trial Enriched by Observational, Real-World Data. J Med Internet Res. 2025;27:e68933. doi:10.2196/68933
