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The incidence of type 1 diabetes in children and adolescents significantly increased during the Covid-19 pandemic compared to pre-pandemic levels, according to a recent meta-analysis.
Suggestions of an association between infection with Covid-19 and a new diagnosis of of type 1 and type 2 diabetes emerged early in the pandemic. However, the causal mechanisms responsible are unclear. Moreover, understanding the nature of any relationship between diabetes and infection with Covid-19 is complicated by several factors including the seasonality of diagnoses and evidence of an estimated 3.4% annual increase in the incidence of the condition.
In trying to untangle the potential association between the rise in cases of type 1 diabetes and infection with Covid-19, a team of Canadian researchers, writing in JAMA Network Open, compared the incidence rates of paediatric diabetes during and before the Covid-19 pandemic.
The team undertook a systematic review and meta-analysis of all medical databases, using subject headings and text terms related to Covid-19, diabetes and diabetic ketoacidosis (DKA). Studies were included in the analysis if these reported differences in incident diabetes cases during compared to before the pandemic, among individuals under 19 years of age.
Researchers set the primary outcome as the change in the incidence rate of paediatric diabetes from before and during the pandemic. The secondary outcome was the change in the incidence rate of DKA among youths with new-onset diabetes during the pandemic.
Type 1 diabetes incidence and Covid-19
In total, 42 studies with 102,984 incident diabetes cases were included in the analysis.
The type 1 diabetes incidence rate was 14% higher during the first year of the pandemic compared with the pre-pandemic period (incidence rate ratio, IRR = 1.14 95% CI 1.08 – 1.21). Nevertheless, this rate increased further during months 13 to 24 of the pandemic compared to the pre-pandemic level (IRR = 1.27, 95% CI 1.18 – 1.37). There was also a higher incidence of DKA compared to before the pandemic (IRR = 1.26, 95% CI 1.17 – 1.36).
The underlying mechanisms responsible for this observed increase are unclear and require further investigation.
