Effect of COVID-19 vaccine on blood glucose metrics in Arabic people with type 1 diabetes.

Introduction: People with diabetes are at a higher risk for coronavirus disease-19 (COVID-19) and hence are prioritized for vaccination. The aim of the current study was to investigate the effects of COVID-19 vaccination on blood glucose control in Arabic people with type 1 diabetes (T1D). Secondary aim was to compare the responses between the two vaccines approved for use in Kuwait. Method: This retrospective study compared ambulatory glucose metrics, using a continuous glucose monitoring device, measured for 14 days before, and 7 days and 14 days after, the first and second dose of the COVID-19 vaccine in Arabic people with Type 1 diabetes (T1D). We also explored possible links with vaccine type and other clinical characteristics. Glucose metrics calculated were time in range (TIR, 3.9-10 mmol/L), time above range (TAR, 10.1- 13.9 mmol/L or >13.9 mmol/L), time below range (TBR, 3- 3.9 mmol/L or <3 mmol/L) and glucose variability (CV). Results: We enrolled 223 participants in the study. Over the 7 days period after the first vaccination dose there was a decrease in TIR (mean difference (SD) -1.9% ± 14.8%; p = 0.05) and increase in TAR >10 mmol/L (2.2% ± 15.9%; p = 0.04), with no effects on TBR. These effects were not seen after the second dose or 14 days after either dose. There was a decrease in CV over the 7 days period after the first (-1.2% ± 7.4%; p = 0.02) and second vaccine doses (-1.1% ± 6.9%; p = 0.03), with no effects noted 14 days after either dose. In subgroup analysis similar effects on TIR and TAR were also seen in those who had received the viral vector-based vaccine, but not the mRNA-based vaccine, although the decrease in CV was seen in those who had received the mRNA based vaccine but not the viral vector-based vaccine. Conclusion: We found a temporary impairment in glucose control in the first 7 days, particularly among individuals receiving viral vector vaccines. The group receiving mRNA vaccine was likely to experience an increase in glucose levels above the target range. However, the temporary change in metrics appears to return to pre-vaccination levels after one-week post-vaccination. The effects on glycemic parameters were more neutral after the second dose.

Glycaemic control during the lockdown for COVID-19 in adults with type 1 diabetes: A meta-analysis of observational studies.

AIMS: To assess the effects of lockdown due to COVID-19 pandemic on glucose metrics, measured by glucose monitoring systems, in adult individuals with type 1 diabetes. METHODS: We conducted a systematic literature search for English language articles from MEDLINE, Scopus and Web of Science up to February 28, 2021, using "diabetes", "lockdown", and "glucose" as key search terms. Time in range (TIR) was the main outcome; other metrics were time above range (TAR), time below range (TBR), mean blood glucose (MBG) and its variability (%CV), estimated HbA1c (eA1c) or glucose management indicator (GMI). RESULTS: Seventeen studies for a total of 3,441 individuals with type 1 diabetes were included in the analysis. In the lockdown period, TIR 70-180 mg/dl increased by 3.05% (95% CI 1.67-4.43%; p < 0.0001) while TAR (>180 mg/dL and > 250 mg/dL) declined by 3.39% (-5.14 to -1.63%) and 1.96% (-2.51 to -1.42%), respectively (p < 0.0001 for both). Both TBR < 70 and <54 mg/dL remained unchanged. MBG slightly decreased by 5.40 mg/dL (-7.29 to -3.51 mg/dL; p < 0.0001) along with a reduction in %CV. Pooled eA1c and GMI decreased by 0.18% (-0.24 to -0.11%; p < 0.0001) and a similar reduction was observed when GMI alone was considered (0.15%, -0.23 to -0.07%; p < 0.0001). Sensor use was only slightly but not significantly reduced during lockdown. CONCLUSIONS: This meta-analysis shows that well-controlled people with type 1 diabetes on both MDI and CSII with continuous or flash glucose monitoring did not experience a deterioration in glucose control throughout the COVID-19 lockdown, showing a modest, though statistically significant improvement in many glucose control parameters.