CGM tied to reduced time spent in hypoglycaemia in patients with T1D
The use of continuous glucose monitoring (CGM) is associated with a decreased amount of time spent in hypoglycaemia in patients with type 1 diabetes (T1D), according to a study presented at EASD 2017.
This randomized crossover study analysed 161 adults with T1D (mean age 43.7 years, 45.3 percent women, mean HbA1c 70 mmol/L) who were treated with multiple daily insulin (MDI) injections. Participants were randomized to start either CGM treatment (Dexcom G4 device) or self-measurement of blood glucose (SMBG) treatment for 26 weeks, followed by a washout period of 17 weeks before crossing over to the other treatment for another 26 weeks. [EASD 2017, abstract 715]
Overall, participants spent significantly less time in hypoglycaemia (<3.9 mmol/L) during CGM treatment than during the SMBG treatment (2.8 percent vs 4.8 percent). Participants with HbA1c <3 mmol/L also had a reduced time spent in hypoglycaemia with CGM vs SMGB treatment (0.8 percent vs 1.9 percent).
When the analysis was stratified by HbA1c level, a significant reduction in time spent in hypoglycaemia was observed with CGM treatment compared with SMBG treatment during daytime (from 6:00 am to 11:59 pm, 49 vs 30 minutes) and nighttime (from midnight to 5:59 am, 19 vs 10 minutes) among participants with HbA1c <3.9 mmol/L.
Among participants with HbA1c <3 mmol/L, time spent in hypoglycaemia was also reduced in the CGM vs the SMGB arms (8 vs 18 minutes at daytime and 3 vs 9 minutes at nighttime).
“The improvement in time spent in hypoglycaemia disappeared when CGM was not used,” according to lead author Arndis Olafsdottir, a registered nurse and junior researcher from the Department of Molecular and Clinical Medicine at the University of Gothenburg, Sweden.
Based on the Hypoglycaemic Confidence Scale (HCS) responses, the patients’ confidence in managing a hypoglycaemic episode significantly improved during CGM treatment, with an improvement in HCS score from 3.27 to 3.4.
In addition, significant improvements were noted in four out of the nine items in HCS, with most patients expressing confidence in identifying and managing a hypoglycaemic event before it occurs (p=0.0033), avoiding serious hypoglycaemic complications in general (p=0.002) or in social settings (p=0.016), and carrying on with their duties despite the risk of hypoglycaemia (p=0.022).“[Overall,] CGM [treatment] reduces time spent in nocturnal and daytime hypoglycaemia in T1D adults on MDI. CGM also increases confidence in avoiding hypoglycaemia and problems related to them,” Olafsdottir added.