3 | Discussion
Diabetes mellitus is a well-known risk factor for worse clinical
outcomes in patients with COVID-19, which has also, significantly
affected blood glucose control in patients with diabetes mellitus,
directly by striking changes in patients’ metabolism with significant
elevations in blood glucose and indirectly by the impact of the pandemic
on the management of blood glucose or the use of proposed treatments for
the infection that also affect glucose homeostasis [9, 10].
Furthermore, people with metabolic diseases seem to be more often
affected by long-COVID and experience more long-term consequences than
people without diabetes [11]. Post-COVID-19 syndrome could affect
patients with diabetes differentially by exacerbating signs of diabetes
as asthenia [12, 13]. Also, it has been suggested that COVID-19
might be involved in developing acute diabetes mellitus in certain
patients [14, 15]. A rise in new-onset diabetes was found in several
studies, particularly in patients with long-COVID [16, 17].
SARS-CoV-2 infection might also lead to type 1 [18] or type 2
diabetes [17] or central diabetes insipidus [19] through complex
and differing mechanisms. Glycemic parameters in patients with new-onset
diabetes during the COVID-19 pandemic are otherwise more severe than in
patients with new-onset diabetes before the pandemic [16, 17]. Our
patient was diagnosed with type 2 diabetes after infection by SARS-Cov
2.
Increases in the number of diabetes diagnoses after acute SARS-Cov 2
infection have been reported in children and adults [8, 18]. The
time to onset of diabetes after infection with SARS-Cov 2 was also
variable according to the studies [14] ranging from more than 30
days in patients under 18 years of age [18], to an average of 2.9
months in patients aged under or aged of 65 years [20] and an
average of 4.6 months among those with an average age of 65 [21]. A
growing body of evidence suggests that beyond the first 30 days, the
acute phase of the disease, people with COVID-19 could experience
post-acute sequelae which can involve pulmonary and extrapulmonary organ
system manifestations, including diabetes outcomes [20]. One study
found that diabetes mellitus incidence remained elevated for at least 12
weeks following COVID-19 before declining [22]. Our HCW developed
diabetes nine weeks after acute SARS-Cov 2 infection, which is the line
with the reported duration in the literature.
Regarding the mechanisms of the onset of diabetes, they were varied.
Long-term follow-up studies of COVID-19 were conducted to further define
the potential association between COVID-19 and increased diabetes risk
and to explain mechanisms of appearance. The mechanisms claiming the
association between COVID-19 and the risk of diabetes are not completely
clear [8]. The current literature proposes that SARS-CoV-2 may
involve the pancreas [23] through several mechanisms such as
cytolytic effects of the virus on pancreatic β-cells, activation of the
hypothalamic-pituitary-adrenal and sympathoadrenal axes causing an
increase in counterregulatory hormones, activation of the
renin-angiotensin system resulting in unopposed deleterious actions of
angiotensin II, and enhanced autoimmunity [24, 25]. In other
studies, direct infection of pancreatic cells seems, on its own,
unlikely to fully explain new-onset diabetes in people with COVID-19.
Other potential hypotheses suggest autonomic dysfunction, hyperactivated
immune response or autoimmunity, and persistent low-grade inflammation
leading to insulin resistance [26-29]. However, some studies have
reported risk factors for the onset of diabetes after COVID-19
infection. People older than 65 years or with cardiovascular diseases,
hypertension, hyperlipidemia, or prediabetes are considered at higher
risks and burdens than people without these conditions [17]. Our
case had dyslipidemia and a history of diabetes in the mother. Risks and
burdens of post-acute outcomes also increased according to the severity
of the acute phase of COVID-19 and the intensity of care during the
acute phase of the infection. They were significant among both
non-hospitalized persons, the group that represents most people with
COVID-19, and hospitalized patients after COVID-19 diagnosis [17].
Our patient developed a moderate form of COVID-19 which did not require
hospitalization. Furthermore, it was also mentioned that diabetes could
potentially be attributed to chronic physical inactivity, especially in
the circumstances of the COVID-19 pandemic [30]. It was reported
that the increase in chronic non-communicable diseases was due to the
reduction of physical activity following restrictive measures consisting
of mandated physical confinement and perimeter closures of localities
[31] as those token in Tunisia during the pandemic.
In addition, a direct effect of the virus on the development of diabetes
by striking increased release of cytokines and inflammatory mediators,
leading to increased insulin resistance and associated hyperglycemia,
has been also mentioned in the literature [32, 33]. This effect has
also been reported in people with no or few diabetes onset factors.
Diabetes could manifest in people at low risk and COVID-19 could likely
amplify baseline risks and further accelerate the onset of the disease
in people already at high risk [17]. Besides, a study of two large
databases of more than 2.5 million children indicated that those with
COVID-19 presented a higher risk of new diabetes than those without
COVID-19 [18]. An analysis, which is not yet peer-reviewed, of 1.8
million people aged younger than 35 years also suggested an increased
risk of diabetes within, but not
beyond, the first 30 days after SARS-CoV-2 infection [34].
These findings confirm the interest of the post-COVID diabetes screening
in all patients who had the disease regardless of the patient’s age and
clinical history. The observed Increase in the number of diabetes
diagnoses after acute SARS-Cov2 infection highlights the importance of
COVID-19 prevention strategies. Follow-up for healthcare workers in the
occupational medicine department is therefore necessary after infection
with the SARS-Cov 2 virus. This screening may help establish prevention
strategies in healthcare workers, including anti-COVID-19 vaccination
for eligible persons, chronic disease prevention and management, and
monitoring for long-term consequences as signs of new diabetes following
SARS-CoV-2 infection. This screening should be continued until at least
one year after COVID-19 diagnosis. In fact, according to Narayan et al,
people who survived the first 30 days of SARS-CoV-2 infection were at
increased risk of incident diabetes at 12 months, compared with people
without COVID-19 [35]. The inclusion of physical exercise as a
possible prevention strategy of COVID-19 by reinforcing the immune
defense, and strengthening rehabilitation after post- COVID-19 syndrome
could be important also to consider [31, 36]. Factors postulated to
influence long-term complications of COVID-19 should besides be
measured, including the severity of infection, the viral load, and the
presence of antibodies signaling auto-immune attack [35, 37]. A
multidisciplinary collaboration including occupational physicians,
diabetologists, and immunologists is thus necessary to ensure the early
management and medical follow-up of healthcare workers diagnosed with
diabetes to avoid its complications if not diagnosed at time and to
better understand the mechanisms of occurrence of this pathology in
post-COVID.