COVID-19 and diabetes: What do we (not) know?

The challenge of diabetes has never been so great. Cases of diabetes continue to rise, with nearly half a billion people worldwide now living with the condition1. There are 4.8 million people in the UK living with diabetes – the condition is serious and life-threatening, and this has been brought into sharp focus by the COVID-19 pandemic. We’ve learnt in recent months that the virus has disproportionately affected people living with diabetes – around a third of those dying in the UK from the virus had the condition3, this compares to population prevalence of diabetes of around 7%4. We’ve also learnt that the relentlessness of managing diabetes has been made only harder by COVID-19. Our supporters tell us that many routine diabetes services have been disrupted, that it’s been more difficult to access healthy food and get enough physical activity, and that the worry of catching the virus and returning to workplaces is taking its toll.

COVID-19 and diabetes

The pandemic has seen the research community galvanised into action and respond to it with innovation and speed. Since winter last year we’ve gone from having virtually no published studies on COVID-19 to nearly 6,000 (Pubmed search, correct up to 10th September 2020). And while we’ve already learnt a lot about how COVID-19 affects people with diabetes, there is still much more we need to understand to inform policy and care, and save lives. In response to the urgent need for answers, Diabetes UK has recently announced, in partnership with JDRF, Moorfields Eye Charity and Fight for Sight, a combined commitment of £400,198 to support five new research projects on diabetes and COVID-19.

Large UK population studies have consistently shown that people with diabetes are at increased risk of dying from the virus3,5,6. Research by the NHS found that those with type 1 have 3.5 times the risk and those with type 2 twice of dying compared to people without the condition3. While these population-level statistics are concerning, it’s important to understand that an individual’s risk of poor outcomes from COVID-19 is dependent on much more than their diabetes. We know that age is the dominant risk factor, with the vast majority of deaths occurring in the 70 years plus age groups3. We’ve also learnt that ethnicity, socioeconomic status, sex, bodyweight, long-term blood sugar control and a whole host of other factors contribute to the huge variation in individual risk between people with diabetes5. But we also know that when we statistically strip away the effects of other risk factors, diabetes remains an independent risk factor6.

Why does diabetes make people particularly vulnerable to COVID-19? There is no persuasive evidence that this is because they are more likely to catch the virus in the first place and we, as yet, have no answers. Research is underway to understand the biological reasons why diabetes might allow the virus to get a firmer hold. A pro-inflammatory state, vascular damage, and upregulation of ACE2 receptors, all of which are associated with diabetes, have been suggested as potential contributors to severe COVID-19 in people with the condition7. The type of basic science needed to explore the virus’ mechanisms of attack and its interplay with diabetes takes time and is vital for understanding how we might better protect and care for people living with the condition.

Recently emerging is some limited and anecdotal evidence that COVID-19 might be triggering new cases of type 1 diabetes, accelerated progression of type 2 diabetes, or a new type of diabetes altogether. Again, we need to look to science for answers – only long-term studies will reveal what’s really going on and, crucially, help to inform care. To find answers, a global database of new cases of diabetes in patients with COVID-19, called the CoviDiab Registry Project, has been established8. The Post-HOSPitalisation COVID-19 (PHOSP COVID) study, a national consortium to understand and improve long-term health outcomes in people who have had the virus, will also shed light on the long-term implications of COVID-19 for people with diabetes.

The future: Funding research

Investment in science has never been more important. Last year, UK charities, including Diabetes UK, invested £1.9 billion into medical research – more than half of all public spending nationally. But the sector is facing a dramatic and deeply concerning drop in income due to COVID-19 and research is at risk. The Association of Medical Research Charities (AMRC) has predicted a £310 million shortfall in research spend in 2020/21, with an estimated four-year recovery period.

AMRC and its members, including Diabetes UK, are urging the Government to commit to the Life Sciences Charity Partnership Fund (support at #Researchatrisk) co-investment scheme. This will allow medical research charities to emerge from this pandemic intact and in a strong position to continue to fund research that transforms healthcare and saves lives. Now more than ever, investment is needed in the sector to mitigate the impact of COVID-19 and future pandemics, on the health of the nation.

References

1 International Diabetes Federation, (2019). IDF Diabetes Atlas, 9th edn.Brussels, Belgium: IDF. Available at: https://www.diabetesatlas.org

2 Estimated from NCVIN (2016), Diabetes Prevalence Model for England + estimated growth between 2015–2020 from APHO (2010) Prevalence Models for Scotland and Wales.

3 Barron, E., Bakhai, C., Kar, P., Weaver, A., Bradley, D., Ismail, H., Knighton, P., Holman, N., Khunti, K., Sattar, N. and Wareham, N.J., (2020). Associations of type 1 and type 2 diabetes with COVID-19-related mortality in England: a whole-population study. The Lancet Diabetes & Endocrinology.

4 Diabetes Prevalence Model. Quality and Outcomes Framework (QOF) 2017/18. Public Health England. Available at: https://fingertips.phe.org.uk/profile/diabetes-ft/data

5 Holman, N., Knighton, P., Kar, P., O’Keefe, J., Curley, M., Weaver, A., Barron, E., Bakhai, C., Khunti, K., Wareham, N.J. and Sattar, N., (2020). Risk factors for COVID-19-related mortality in people with type 1 and type 2 diabetes in England: a population-based cohort study. The Lancet Diabetes & Endocrinology.

6 Williamson, E.J., Walker, A.J., Bhaskaran, K., Bacon, S., Bates, C., Morton, C.E., Curtis, H.J., Mehrkar, A., Evans, D., Inglesby, P. and Cockburn, J., (2020). OpenSAFELY: factors associated with COVID-19 death in 17 million patients. Nature.

7 Apicella, M., Campopiano, M. C., Mantuano, M., Mazoni, L., Coppelli, A., & Del Prato, S. (2020). COVID-19 in people with diabetes: understanding the reasons for worse outcomes. The Lancet Diabetes & Endocrinology.

8 Rubino, F., Amiel, S. A., Zimmet, P., Alberti, G., Bornstein, S., Eckel, R. H., … & Del Prato, S. (2020). New-Onset Diabetes in Covid-19. New England Journal of Medicine.