Outcomes
Diabetes was a common comorbidity in COVID-19 patients who were either
admitted to ICU or died. 20-22 In a meta-analysis that
included 1382 patients hospitalised for COVID-19, diabetes was
identified as a risk factor for both ICU admission (OR 2.79, 95 % CI
1.85 to 4.22, p < 0.0001) and mortality (3.21, 1.82 to 5.64, p
< 0.0001). 23 In another meta-analysis of
1936 COVID-19 patients, diabetes significantly correlated with COVID-19
severity (OR 2.67, 95% CI 1.91 to 3.74, P<0.01).24 Prevalence of diabetes was also double in patients
with COVID-19 who required ICU admission compared to those who did not.25 Diabetes was the second most common morbidity in
patients who reached a composite outcome of mechanical ventilation or
death (26.9%) only second to hypertension (35.8%).26 An outcome study has shown that in patients with
COVID-19 who developed acute respiratory distress syndrome (ARDS), more
patients had diabetes (19.0%) compared with those who did not (5.1%),
respectively (difference, 13.9%, 95% CI 3.6% to 24.2%).27 It has also been reported that diabetes was the
most common morbidity (22% in one study and 60% in another) of
patients who died in hospital. 28, 29 Compared with
patients with non-severe COVID-19, diabetes was more common in severe
cases although it did not reach statistical significance (OR 2.07, 95%
CI 0.89 to 4.82). 30 In a US retrospective chart
review of all patients enrolled in a follow up telemedicine outpatient
clinic, the rate of hospitalisation for patients with diabetes was
double (10.2%) the rate of hospitalisation for all other patients
(5.1%) suggesting that the risk of severe COVID-19 is increased in
individuals with diabetes. 31 Retrospective Chinese
report has shown that compared with non-diabetes subjects, patients with
diabetes were more likely to develop severe COVID-19 disease (P=0.028)
with more complications including acute respiratory distress (38.1% vs
19.5%, P=0.001), acute cardiac injury (14.5% vs 5.1%, P=0.016) and
non-invasive and invasive mechanical ventilation (P=0.037).32 Diabetes as well as fasting blood glucose were
independent risk factors for COVID-19 mortality (HR 3.641, 95% CI 1.086
to 12.214, P=0.036 and 1.187, 1.078 to 1.306, P<0.001,
respectively) after adjustment for age, cardiovascular disease, chronic
kidney disease and laboratory markers. 32 The recently
reported British database analysis of 17,425,445 NHS registered adults
showed that 5,683 deaths were attributed to COVID-19 and uncontrolled
diabetes (HbA1c >=7.5%) was independent risk factor for
mortality (HR 2.36, 95% CI 2.18 to 2.56). 33 Main
studies reporting outcomes of patients with diabetes and COVID-19 are
summarised in Table 3.