A reminder system for postpartum diabetes screening after gestational diabetes: a randomized clinical trial

To evaluate if a reminder postpartum screening system, providing patients with laboratory requisition on the postpartum ward followed by a telephone reminder one week prior to their 6 weeks appointment, would increase the diabetes mellitus screening rate.

Parallel group, open label, multicenter randomized trial. Patients were recruited between July 2015 and March 2016. All women with gestational diabetes mellitus in their index pregnancy with access to a mobile or landline phone were eligible for participation. Gestational diabetes mellitus diagnosis was made with a one-hour 50 g OGTT ≥135 mg/dl, and a subsequent 3 h OGTT with ≥2 values above fasting 95 mg/dl, 1 h 180 mg/dl, 2 h 155 mg/dl, and 3 h 140 mg/dl. Participants were assigned in a 1:1 ratio to "reminder system" (intervention group) or to "routine care (control group)." Those assigned to the reminder system were provided with two reminders. The first was a laboratory requisition slip given to them while on the postpartum ward. The second was a telephone reminder on the fifth week postpartum, consisting of a standardized script to encourage contacted participants to complete the screening test during the sixth week postpartum. The primary outcome was completion of the two-hour 75 g OGTT 6-12 weeks postpartum.

A total of 75 patients were included in the study. Thirty-eight patients were randomized to the reminder system, and 37 patients were randomized to routine care. A total of 22 women (29.3%) completed the test. In the "reminder" group, 31.6% completed the test, and in the "routine care" group 27% of patients completed the test. This increase in screening uptake in the reminder group was not noted to be statistically significant (p=.8). When evaluating whether perinatal or sociodemographic factors influenced the effect of reminder systems on screening uptake, only insurance type was noted to have a statistically significant influence. Screening uptake was significantly increased in patients with public insurance assigned to "reminder group" (13.5%) compared to those assigned to "routine care" (0%). Of those women who completed the test, seven patients (31.8 %) were diagnosed with prediabetes and none with diabetes.

Telephone reminders were not found to have a significant impact on increasing postpartum screening for diabetes. The exception was among the publicly insured population. These findings suggest a targeted role for reminder systems, particularly among those with socioeconomic disadvantage.