Any role of frailty?
Frailty has not been formally assessed as a risk factor for COVID-19
infection in people with diabetes. However, due to old age and multiple
comorbidities being associated with worse outcome in a proportional
fashion, it is likely that frailty is a confounding unmeasured factor.51 Diabetes is known to increase the risk of frailty.52 Frailty is a syndrome that is characterised by
multisystem, including immune system, dysregulation which leads to
reduced physiologic reserve and increased risk of adverse health
outcomes including increased susceptibility to severe infections.
Frailty has been shown to be associated with poor post-vaccination
immune response, increased rates of influenza like illness and
laboratory-confirmed influenza infection. 53 In a
prospective cohort study in a tertiary hospital investigating older
patients (aged ≥65 years) admitted with community acquired pneumonia,
nursing home residency (a proxy for frailty) was an independent
predictor of viral pneumonia (relative risk {RR} 3.06, P = 0.01) which
highlights the role of frailty in institutionalised populations for the
increased risk of viral illness. 54 In the British
cohort study of patients with diabetes mellitus and COVID-19, the
relationship of BMI association with the risk of COVID-19
related-mortality was U-shaped. The risk was greatest for those with
very high BMI and the nadir of risk being in those with a BMI 25-29·9
kg/m2. The authors suggested that the higher risks in
people with lower BMI could be linked to the effect of confounding by
factors that are associated with weight loss which have either not been
considered in their analysis. 17 Therefore, frailty
may be an unmeasured factor for adverse outcome in people with diabetes
and COVID-19.