Risks of and risk factors for COVID-19 disease in people with diabetes: a cohort study of the total population of Scotland
Population level review (n=5,463,000) found that a larger portion of the Scottish population with diabetes developed critical care unit treated COVID-19 than those with without diabetes (0.3% vs 0.1%, OR 1.395, p<0.0001). The OR was 2.4 for type 2, and 1.4 for type 2 diabetes
Source:
The Lancet Diabetes & Endocrinology
SPS commentary:
A related editorial discusses this research. It concludes that more insight into the mechanisms leading to severe COVID-19 is urgently needed. The risk conferred by diabetes is probably related in part to hyperglycaemia, which impairs host defences, but the role of other factors, such as specific antihyperglycaemic drugs, in-hospital metabolic decompensation, and increased coagulation activity, remains to be defined. It is noteworthy that even mildly decreased estimated glomerular filtration rate is a strong risk factor for severe COVID-19. More insight is also needed into the roles of ethnicity, high blood pressure (which is surprisingly associated with reduced risk and current smoking (which is either not associated or, counterintuitively, associated with reduced risk). BMI appears non-linearly associated with risk, with nadirs reported at around 30 kg/m2 or 25.0–29.9 kg/m2. Such a pattern, if causal, suggests complex biology. Regardless, all these associations are subject to bias through residual or unmeasured confounding, or overadjustment. For example, obesity is associated with low vitamin D status, which itself might increase risk.