DC2421 - Preliminary analyses from a step count and weight track and target Feasibility Trial in Gestational Diabetes

Blinded Abstract: Background

Device-based physical activity and weight self-monitoring are understudied in gestational diabetes (GDM), despite the importance of health behaviours to maternal and fetal outcomes.

Methods

We created algorithms for weekly steps/day and weight change goals, considering guidelines and prior week values (‘track-and-target’), and tested these through a 5-Canadian city GDM feasibility trial across five Canadian cities (2019-2023). We randomized participants to a web resource (i) aloneonly; or with (ii) track-and-target; (iii) weekly telephone coaching; or (iv) both (entry to 37 weeks). We sought 225 participants (consensus-based) to assess feasibility metrics and explore between-group differences in steps/day and weight.

Results

Among 997 interested (76.2% of 1,308 contacted), 26.4% were eligible. Of 227 randomized, 88.1% completed final questionnaires and 76.6% provided final steps data. At trial entry, participants averaged 34.9 (SD 19.7) years, 28.8 (2.0) weeks gestation, 80.4 (17.5) kg, and 6,385 (3,406) steps/day. Call completion was 71.0% in the coaching and 66.8% in the combined arm. Actual vs. target weekly differences averaged -485 steps/day (95% CI -652 to -318) in track-and- target and -800 (95% CI -993 to -608) in combined arms; the former had a 1,291 lower reduction in steps/day than the web resource alone arm (95% CI 261 to 2,320; adjusted linear regression). Mean weight change was within optimal range for the trial period, across arms.

Interpretation

The track-and-target approach mitigated pregnancy-related decline in physical activity. It was not enhanced by coaching. Future trials will examine the approach’s impact on diabetes, hypertension, and size for gestational age.