Prospective transitions in hemoglobin A1c following gestational diabetes using Multistate Markov Models.

Objective: We characterized the state-to-state transitions in postpartum A1c levels after gestational diabetes, including remaining in a state of normoglycemia or transitions between prediabetes or diabetes states of varying severity.

Methods: We used data from the APPLE Cohort, a postpartum population-based cohort of individuals with gestational diabetes between 2009-2011and linked HbA1c data with up to 9 years follow-up (N=34,171). We examined maternal sociodemographic and perinatal characteristics as predictors of transitions in A1c progression using Markov multistate models.

Results: In the first-year postpartum following gestational diabetes, 45.1% of people had no-diabetes, 43.1% had prediabetes, 4.6% had controlled diabetes and 7.2% had uncontrolled diabetes. Roughly two-thirds of individuals remained in same state in the next year. Black individuals were more likely to transition from pre-diabetes to uncontrolled diabetes (aHR: 2.32 95% CI: 1.21 ,4.47) than White persons. Perinatal risk factors were associated with disease progression and lower likelihood of improvement. For example, hypertensive disorders of pregnancy were associated with a stronger transition (aHR: 2.06 95% CI: 1.39, 3.05) from prediabetes to uncontrolled diabetes.

Conclusions: We illustrate factors associated with adverse transitions in incremental A1c stages and describe patient profiles who may warrant enhanced postpartum monitoring.