Flash Glucose Monitoring Lowers HbA1c, Rates of DKA in Patients with Type 1 Diabetes

An analysis of data from more than 14,000 patients with type 1 diabetes in Scotland is shedding further light on the improvements in HbA1c levels and reductions in diabetic ketoacidosis (DKA) rates associated with the initiation of flash monitor usage.

As use of flash glucose monitoring technology becomes more commonplace, results provide evidence encouraging further uptake of the technology, providing evidence of clinically meaningful improvements in HbA1c and rates of DKA among users in real-world settings.

“Flash glucose monitoring use in Scotland has been associated with clinically important improvements in HbA1c, especially in individuals with high baseline HbA1c who have the most to gain in reducing the risk of diabetes complications. Historically, reducing rates of DKA has proven to be an extremely difficult task and uptake of effective interventions has often been relatively low. The striking reduction in DKA across the sociodemographic spectrum following FM use is of major clinical importance,” wrote investigators.

With the technology becoming freely available in Scotland in 2018, investigators sought to assess how use of flash glucose monitoring might influence glucose control and DKA rates in a real-world setting. With this in mind, a team of investigators designed the current study on behalf of the Scottish Diabetes research Network Epidemiology Group as a retrospective observational cohort study using data from the Scottish Care Information-Diabetes Collaboration (SCI-DC) database.

With a study period of 2014 through mid-2020, investigators sought to identify all patients with type 1 diabetes with use of flash monitoring. Of note, mid-2020 was chosen as a cut-off date for inclusion to limit the number of patients with no post-initiation HbA1c measurements. The exposure of interest for the study was flash monitor initiation. Outcomes of interest included within-person change from baseline in HbA1c, which was assessed using linear mixed models accounting for within-person pre-exposure trajectory, and rates of DKA and severe hospitalized hypoglycemia, which were assessed using hospital admission and mortality data.

Upon analysis, investigators found the crude prevalence of individuals with type 1 diabetes reporting use of flash monitoring increased from 3.1% in 2017 to 45.9% by mid-2020, which yielded an overall study population of 14,682 individuals. Investigators noted there were large variations in usage rates based on age and socioeconomic status, with 64.3% of individuals younger than 13 years reporting use compared to 32.7% among those aged 65 and older and 54.4% of those in the least-deprived quintile reporting use compared to 36.2% of the most-deprive quintile.

Results of the investigators’ analysis suggested the median within-person channel in HbA1c in the first year following flash monitoring initiation was -2.5 (IQR, -9.0 to 2.5) mmol/mol. Investigators pointed out this change varied according to pre-usage HbA1c, with a median reduction of -15.5 (IQR, -31.0 to -4.0) mmol/mol in those with HbA1c an HbA1c greater than 84 mmol/mol and 1.0 (IQR, -2.0 to 5.5) mmol/mol in those with HbA1c less than 54 mmol/mol. Investigators highlighted results suggested significant HbA1c reductions were observed in all age bands, sexes, and socioeconomic strata, and regardless of prior or current pump use, completion of a diabetes education program, or early flash monitoring adoption.

Analysis of DKA rates indicated rates decreased after flash monitoring among the overall cohort and in all strata apart from adolescents. In analysis accounting for pre-exposure trend, the estimated overall reduction in DKA rate ratio was 0.59 (95% CrI, 0.53-0.64) after flash monitoring initiation compared to before initiation. Among a subgroup of patients considered to be at elevated risk of severe hospitalization for hypoglycemia, results suggested FM initiation was associated with an estimated reduction in events rates of 0.25 (95% CrI, 0.20-0.32) compared to before flash monitoring initiation.

This study, “Flash monitor initiation is associated with improvements in HbA1c levels and DKA rates among people with type 1 diabetes in Scotland: a retrospective nationwide observational study,” was published in Diabetologia.