Infection with COVID-19 increases the risk of type 2 diabetes by 50% compared to other acute upper respiratory tract infections
The type 2 diabetes risk after an acute infection with COVID-19 is as much as 50% higher in comparison to other acute upper respiratory tract infections. This was the main finding from a retrospective analysis by researchers from the Institute for Biometrics and Epidemiology, German Diabetes Center, Düsseldorf, Germany.
The development of type 2 diabetes after infection with COVID-19 has been recognised and evidenced by impaired glucose homoeostasis due to a viral-associated β-cell destruction. Moreover, other work has found that infection with COVID-19 potentially increases type 2 diabetes risk by induction of insulin resistance, leading to clinically evident hyperglycaemia detectable even in the post-acute phase.
However, there is uncertainty over whether or not these adverse metabolic disturbances are merely transient or if infection with COVID-19 does ultimately increase an individual’s subsequent risk of developing type 2 diabetes. For the present study, the German team retrospectively examined the incidence of type 2 diabetes over a longer time frame, after infection with COVID-19, among patients with mild infections, i.e., those managed in primary care. In order to show that the development of type 2 diabetes was a unique feature of COVID-19 as opposed to a general response to viral infections, the team included a control group of individuals who experienced other acute upper respiratory tract infections (AURIs). Propensity score matching was carried out based on sex, age and co-morbidities and the presence of newly diagnosed type 2 diabetes was extracted from the electronic medical records.
Type 2 diabetes risk and infection with COVID-19
A total of 35,865 individuals with a mean age of 42.6 years (45.6% women) were propensity-matched and followed-up for a median of 119 days (COVID-19) or 161 days (AURI patients). Although disease severity was generally mild, a similar proportion from each cohort were hospitalised due to their infection (3.2% COVID-19 vs AURI 3.1%).
After matching 1:1 COVID-19 and AURI individuals (9823 pairs) the type 2 diabetes incidence after recovery from both infections was 20.5 per 1000 person-years in the COVID-19 group and 13.6 in the AURI group (incidence rate ratio, IIR = 1.51, 95% CI 1.05-2.18). However, the risk of developing all other forms of diabetes were not significantly different between COVID-19 and any other AURI (IIR = 1.25, 95% CI 0.60 – 2.59).
Whether or not the incident cases of type 2 diabetes uncovered in the study would resolve over time could not be determined due to the retrospective nature of the study. However, based on these findings, the authors concluded that if other studies confirmed their own results, active monitoring of glucose dysregulation should be instigated after recovery, even from mild forms of COVID-19 infection.
Rathermann W et al. Incidence of newly diagnosed diabetes after Covid-19 Diabetologia 2022