Effectiveness of flash glucose monitoring in patients with diabetes mellitus and high cardiovascular comorbidity: impact on glycemic control, length of hospitalization and rehospitalizations

Background. Currently, continuous glucose monitoring (CGM) systems are widely used in the outpatient management of patients with diabetes mellitus (DM). However, their use for inpatient monitoring is not yet standard. The feasibility of using CGM-derived data during hospital care remains an open question and requires further research. Special attention should be paid to studying the effectiveness of CGM on the manifestations of cardiovascular comorbidity in patients with diabetes mellitus, which is as common a cause of hospitalization as diabetes itself.

Aim. To conduct a comparative analysis of glycemic parameters obtained by flash glucose monitoring versus standard glycemic profile assessment using a glucometer in patients with diabetes mellitus and high cardiovascular comorbidity during inpatient treatment.

Materials and methods. A prospective study included 60 patients with DM who had not achieved glycemic targets and presented with exacerbation of cardiovascular comorbid diseases. Patients in the observation group received a flash glucose monitoring (FGM) system, while patients in the control group underwent 4–5 daily glucose measurements (glycemic profile using a laboratory analyzer). The assessment included glucose levels, time in range (TIR), time above range (TAR), time below range (TBR), and glycemic variability (GV). Comorbidity level was assessed using the CIRS scale. All patients were classified as having high cardiovascular risk.

Results. In the observation group, target glycemic levels were achieved on day 3 (day 6 in the control group, p<0.01). GV was 39.1±1.9% in the observation group vs 47.6±3.2% in the control group (p<0.01). Hospital stay duration was reduced by 42.85% to 4 days (7 days in the control group, p<0.01). In the hospital setting, the time to achieve glycemic targets did not depend on the comorbidity level. Among patients using FGM, no rehospitalizations due to failure to achieve glycemic control were recorded during the prospective follow-up period; GV remained at 11.6±2.2% (with target range maintained >50% of time in 87% of patients).

Conclusion. Flash glucose monitoring technology during inpatient treatment demonstrated comparable accuracy to laboratory analyzer data and significantly improved long-term prognosis.

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