Text Messaging Support for Patients Diagnosed With Impaired Glucose Tolerance During Pregnancy: Nonrandomized Pre-Post Implementation Study Assessing Impact on Postpartum Transitions of Care

Background: Patients with impaired glucose tolerance (IGT) identified during pregnancy who do not develop gestational diabetes mellitus (GDM) often do not receive additional interventions for their long-term metabolic risks. Objective: This nonrandomized pre-post implementation study reports the design process and initial program evaluation for Better Follow-up of Impaired Glucose Tolerance (BRIDGE), a 12-week text-based postpartum support program promoting hemoglobin A (HbA) completion and primary care provider (PCP) visit scheduling for patients diagnosed with IGT during pregnancy, assessing improvement in desired postpartum transition milestones. The 19-month program was divided into 2 arms lasting 9.5 months each, BRIDGE− (SMS text messaging support alone; October 2021-July 2022) and BRIDGE+ (SMS text messaging and IGT-focused postpartum visit; July 2022-April 2023). We aimed to assess whether BRIDGE improved desired postpartum transition milestones. Methods: Patients were eligible for BRIDGE if they received prenatal care at the study site (a northeastern US academic tertiary care center), were diagnosed with IGT during pregnancy, never developed GDM, and could receive English text messages. We performed a program evaluation using a pre/postimplementation design, comparing outcomes for the BRIDGE population to a 19-month historical population. Primary outcomes were (1) completion of HbA testing by 1 year postpartum and (2) PCP visit scheduling by 12 weeks postpartum. A comparative analysis between BRIDGE− and BRIDGE+ was performed. Multivariable logistic regressions controlled for the history of IGT after stepwise backward elimination. Results: In the program evaluation, 503 individuals were included (n=342 in historical population, n=82 in BRIDGE− population, and n=79 in BRIDGE+ population), with similar demographic and clinical characteristics across populations. A total of 212 individuals were screened for eligibility in BRIDGE, and 161 individuals participated in the program. BRIDGE participants had increased odds of HbA completion by 1 year postpartum (39.8% vs 12.5%; adjusted odds ratio [aOR] 4.28, 95% CI 2.71‐6.78) and PCP visit scheduling (31.0% vs 12.0%; aOR 9.58, 95% CI 4.39‐20.9) compared to the historical population. BRIDGE+ patients were more likely to complete HbA testing by 12 weeks postpartum than BRIDGE− participants. Most patients attended scheduled PCP visits, but rates of IGT counseling at PCP visits were low. Conclusions: Individuals with IGT rarely receive targeted interventions during pregnancy or delivery hospitalization. This innovative study demonstrates that individuals with IGT have high rates of uptake for postpartum SMS text messaging support, which tripled completion rates of HbA screening within 1 year postpartum and doubled the scheduling rate for PCP visits by 12 weeks postpartum. While attendance at scheduled PCP visits was very high, <60% of PCP visits included IGT counseling, highlighting key improvement areas in the quality of postpartum transitions to primary care. While a randomized trial is needed to ascertain definitive impact, SMS text messaging support may be an effective tool to improve postpartum transitions of care for this underserved population.