Analysis of continuous glucose tracking data in people with type 1 diabetes after COVID-19 vaccination reveals unexpected link between immune and metabolic response, augmented by adjunctive oral medication.

INTRODUCTION: The COVID-19 vaccination programme is under way worldwide. Anecdotal evidence is increasing that some people with type 1 diabetes mellitus (T1DM) experience temporary instability of blood glucose (BG) levels post-vaccination which normally settles within 2-3 days. We report an analysis of BG profiles of 20 individuals before/after vaccination. METHODS: We examined the BG profile of 20 consecutive adults (18 years of age or more) with T1DM using the FreeStyle Libre flash glucose monitor in the period immediately before and after COVID-19 vaccination. The primary outcome measure was percentage (%) BG readings in the designated target range 3.9-10 mmmol/L as reported on the LibreView portal for 7 days prior to the vaccination (week -1) and the 7 days after the vaccination (week +1). RESULTS: There was a significant decrease in the %BG on target following the COVID-vaccination for the 7 days following vaccination (mean 45.2% ± SE 4.2%) vs pre-COVID-19 vaccination (mean 52.6% ± SE 4.5%). This was mirrored by an increase in the proportion of readings in other BG categories 10.1%-13.9%/≥14%. There was no significant change in BG variability in the 7days post-COVID-19 vaccination. This change in BG proportion on target in the week following vaccination was most pronounced for people taking Metformin/Dapagliflozin+basal-bolus insulin (-23%) vs no oral hypoglycaemic agents (-4%), and median age <53 vs ≥53 years (greater reduction in %BG in target for older individuals (-18% vs -9%)). CONCLUSION: In T1DM, we have shown that COVID-19 vaccination can cause temporary perturbation of BG, with this effect more pronounced in patients talking oral hypoglycaemic medication plus insulin, and in older individuals. This may also have consequences for patients with T2DM who are currently not supported by flash glucose monitoring.

Dapagliflozin: an effective adjunctive treatment in type 1 diabetes.

INTRODUCTION: Many people with type 1 diabetes (T1DM) continue to run high HbA1c levels with an associated elevated risk of cardiovascular events and increased mortality. We describe here how adjunctive prescription of an SGLT2 inhibitor has improved the glycaemic control of several people with T1DM, where the new technology has been intensively deployed. METHODS: We report outcomes of six adults with T1DM who have been given dapagliflozin in East Cheshire, UK. Initiation was with education/support from the diabetes specialist nurses. All had an HbA1c of 70 mmol/mol (8.6%) or more before this was initiated. All had been monitoring glycemia with a FreeStyle Libre monitor for at least 6 months prior to this. RESULTS: The age range was 30-68 years. The mean duration of T1DM was 23.3 ± 5.5 years. All were on a basal-bolus regime. Over a 6 month period, HbA1c fell from 78.5 mmol/mol (9.3%) to 55 mmol/mol (7.2%). The greatest reduction in HbA1c was 57 mmol/mol (7.4%). Analysis of the FreeStyle Libre blood glucose records showed that the proportion of blood glucose readings on target (4-10 mmol/L) increased from 33.1 to 65.2% with the addition of dapagliflozin(P = 0.007). The proportion of blood glucose readings above target (>10 mmol/L) decreased from 68.0 to 26.4%, 6 months after initiation of dapagliflozin (P = 0.005). There was no increase in symptomatic hypoglycemia. CONCLUSION: Dapagliflozin as adjunctive therapy to basal-bolus regime insulin in individuals with T1DM was well tolerated and improved glycemic control with no increase in hypoglycemia. We provide further evidence of the value of this intervention.

The FreeStyle Libre flash glucose monitoring system: how it has improved glycaemic control for people with type 1 diabetes in Eastern Cheshire, UK.

INTRODUCTION: Many people with type 1 diabetes continue to run high HbA1c levels with associated elevated risk of cardiovascular events and increased mortality. We describe here how use of the FreeStyle Libre flash monitor has improved the glycaemic control of many people with type 1 diabetes where the new technology has been intensively deployed. METHODS: We report the outcomes of 92 consecutive adults (18 years of age or more) with type 1 diabetes who have begun using the FreeStyle Libre flash glucose monitor in East Cheshire, UK. Initiation was with education and support from one of the diabetes specialist nurses. An HbA1c of 60 mmol/mol (7.6%) was taken as the threshold for suboptimal glycaemic control. RESULTS: The mean cohort age was 43 years for men and 39 years for women (overall range 17-83 years). In 92 consecutive users, HbA1c decreased by an average of 10.7 mmol/mol (0.98%) after 3 months, and by 16.1 mmol/mol (1.47%) after 6 months. There was also a narrowing of the distribution of HbA1c, with many fewer people running high HbA1c ≥80 mmol/mol (9.5%). After the 6-month follow-up, two 2/92 users did not wish to continue with the monitoring. CONCLUSION: Flash glucose monitoring has great potential for the management of type 1 diabetes in the adult population and improving metabolic control/quality of life for people across the world. The technology provides significantly more data than the intermittent results obtained by traditional subcutaneous blood glucose monitoring, which may not capture intervals of extreme variability or nocturnal events.