T1DM is an endocrine metabolic disease in which pancreas islet β cells are destroyed by the autoimmune system and insulin therapy are required for life. The management of chronic hyperglycemia, hypoglycemia and blood glucose variability in T1DM is the difficulty in clinical treatment at present.Monitoring of glucose levels is essential for achieving target glycemic control and avoiding hypoglycemia, especially in patients with T1DM.
As a new technology,flash glucose monitoring (FGM) has recently been accepted by clinicians rapidly instead of CGM/SMBG. In FGM, glucose data could be stored for up to 8 hours on a sensor and a handheld reader could be used to obtain them conveniently.Moreover, the FGM sensor is factory-calibrated and can be worn for up to 14 days,popular with patients requiring high qualities of life .
In this study we aimed to identify whether using FGM can improve glycemic control among patients with T1DM in Liaocheng district.
The 2017 "International Consensus of Continuous Glucose Monitoring" emphasized that the "three core indicators" of FGM monitoring are TIR, blood glucose variability, and hypoglycemia .In 2019,Marion Fokkert collected daily life data from persons with DM using the FGM system༌finding that after 1-year follow-up༌HbA1c declined from 64mmol/mol to 60mmol/mol.While, patients reported less and less severe hypoglycemias and a more active role toward treatment.Study of Ramzi A Ajjan also displayed similar results.They found that FGM can improve HbA1c and treatment satisfaction without increasing hypoglycemic exposure in insulin-treated type 2 diabetes individuals managed in primary/secondary care centres.The DIAMOND and GOLD studies showed the benefit of CGM in people using conventional MDI treatment as well, which the majority of patients with T1DM use[12, 21].
In our study,HbA1C was 9.05% at baseline,demonstrating T1DM patients’ poor glycemic control in Liaocheng,while it decreased largely after intermittent use of FGM at 48 week(from 9.05༅ to 7.39༅)(p < 0.05),similar with above studies. At the same time, hypoglycemic duration does not increase.Instead,it decreased sharply at the end of study,which demonstrated using FGM was able to improve HbA1C without increase of hypoglycemic time.
Blood glucose variability, also known as blood glucose fluctuations, is an unstable state in which blood glucose levels change between peaks and troughs. IQR is considered the most appropriate value for expressing blood glucose variability  .The results of a large randomized clinical trial known as IMPACT demonstrated that there was apparent improvements in time in range and glucose variability in patients who were randomized to flash CGM. In our research,we also described obvious improvement in TIR at 48 week and reduced IQR,which meant patients of intervention group got good glycemic control and reduced blood glucose variability.
Study of Dunn et al. discovered in real-world conditions, flash glucose monitoring with higher rates of scanning linked to improved glycemic markers, including increased time in range and reduced estimated HbA1c from 8.0–6.7% . Research of Deng mingqun also showed that the FGM-derived TIR could be helpful in the glucose management of Chinese adult T1DM, while glucose variability should be taken into consideration in interpreting the relationship between TIR and HbA1c.Our study got similar results that after intermittent FGM intervention, the TIR value increased from 36.49–62.35% at 48 week, and the HbA1C fell up to 7.39%.
With regard to safety, no sensor-related adverse events occurred and the few events such as insertion and shedding problems were similar to the events observed in other researches [22, 26].
Lots of researches displayed that estimating glycemic control from HbA1c alone is in essence applying a population average to an individual, which can be misleading. Flash glucose monitoring system can provide real-time interstitial glucose levels and trends of glucose levels. Moreover,it has the advantage of being factory calibrated so the user does not have to do any CBG.Beyond that, users could acquire a patient’s CGM glucose profile, which has considerable value for optimizing diabetes management.
Previous studies all focused on the influence of continuous application of FGM for T1DM patients.In China,it’s the first time to discuss the effects of 1- year intermittent use of FGM in T1DM patients,which may be helpful to follow-up studies and application of FGM for diabetes prevention and blood glucose management.
This study has a number of limitations,too. First of all, participants have to realize the intervention, so the research could not be blinded, which may affect the results. Secondly, the intermittent intervention could underestimate the potential benefit of FGM.Thirdly, as data were patient-reported, recall bias may be present.Finally, the current population was a selection of the patients in Liaocheng district, which may implicate selection bias.