Impact of the COVID‐19 pandemic on the glycemic control in people with diabetes mellitus: A retrospective cohort study

AIM: To investigate the impact of the COVID‐19 pandemic and its preventive measures on the glycemic and lipid control in people with diabetes mellitus (DM). MATERIALS AND METHODS: We conducted this retrospective cohort study from April 2019 to March 2021; we termed the period from April 2019 to March 2020 as the pre‐COVID‐19 period, and the period from April 2020 to March 2021 as the COVID‐19 period, and divided each of these two periods into four quarters. RESULTS: In the 1st quarter of the COVID period, when the Japanese government declared the first public health emergency, 3,465 people with diabetes mellitus were receiving treatment, which was 10.4% lower than that in the pre‐COVID period. The annual mean HbA1c level was significantly elevated in the COVID‐19 period. The annual mean total cholesterol (TC) and triglyceride (TG) levels were also significantly higher in the COVID‐19 period. Although there were no significant differences in the glycemic control or annual medication between the two periods in people with type 1 diabetes mellitus, the annual mean HbA1c, TC, and TG levels were significantly higher in the COVID‐19 period in people with type 2 diabetes mellitus. Furthermore, a significant increase in the percentage of prescriptions for glinides, biguanides, sodium‐glucose cotransporter 2 inhibitors, and glucagon‐like peptide‐1 receptor agonists for people with type 2 diabetes mellitus was observed in the COVID period. CONCLUSIONS: It appears from our study that COVID‐19 and its preventive measures had a negative impact on the glycemic and lipid control in people with diabetes mellitus.