Environment and diabetes: Is there an association between the COVID-19 pandemic and phenotypic variation in diabetes?

BACKGROUND. The development of diabetes is linked to the environment, and major lifestyle changes are known to affect the incidence of diabetes. The recent coronavirus disease 2019 (COVID-19) pandemic changed many aspects of daily life and represents a major environmental effect. AIM. To investigate whether the COVID-19 pandemic affected the presentation of diabetes in adults. METHODS. A retrospective fixed cohort study was performed on the Lombard population, one of the hardest hit by the pandemic in Italy. Records from 57870 adults (40-65 years) with diabetes were extracted from the Lombard healthcare database for pandemic (2020-2021) and control (2018-2019) cohorts. Demographic data and data pertaining to concomitant cardiovascular disorders were analyzed. Cohen’s d and rate ratio with 95% confidence interval (CI) were calculated. RESULTS. During the pandemic, the incidence of newly diagnosed diabetes was greater among men aged 40-46 years old (rate ratio = 1.07, 95%CI: 1.01-1.14) and less among older men (59-65 years old; rate ratio = 0.94; 95%CI: 0.90-0.96) compared with the control cohort. The rate of incident diabetic men with hypertension, hyperlipidemia, cardiovascular events, or prescriptions for cardiovascular-acting medications during the pandemic was lower compared with individuals in the control cohort (rate ratio for cardiovascular risk factors = 0.893; 95%CI: 0.87-0.92). A similar pattern was observed among women diagnosed with diabetes during the pandemic (rate ratio for cardiovascular risk factors = 0.899; 95%CI: 0.87-0.93). CONCLUSION. The COVID-19 pandemic was associated with greater incident diabetes in younger individuals with fewer cardiovascular comorbidities and suggest that a potent environmental change such as the pandemic can affect the diabetes phenotype in adults.