Discussion
In the context of developing novel
future strategies for SCIT management during the COVID-19 pandemic, our
research confirmed that long-term efficacy of SCIT is not negatively
affected by COVID-19 related treatment delay, in patients with AR (some
also with asthma). In addition, we also demonstrated the presence of
psychological symptoms, especially depressive symptoms, in patients
undergoing SCIT during the COVID-19 outbreak.
During this study, we found that 25.35% of SCIT patients had withdrawn
from treatment before V1, which is similar to findings from the recent
EAACI survey in which 75% of patients underwent maintenance phase SCIT
during the COVID-19 pandemic32. An objective reason
for this would be that social quarantine was called for in response to
the COVID-19 outbreak; and a subjective reason may be that patients
avoided going to hospital during this time. Currently, the treatment for
patients allergic to inhaled allergens who are not infected with
COVID-19 is controversial. ARIA-EAACI33 recommends the
continuation of SCIT, when infection prevention and control measures are
strictly followed at the hospital according to the request of
WHO34,35. On the contrary, American Academy of
Allergy, Asthma & Immunology (AAAAI) 9 suggests that
it is possible to delay SCIT injections to an interval of once every 2
weeks in the build-up phase, and once every 6 weeks in the maintenance
phase (which matched our study design), or even to suspend treatment
until social quarantine is cancelled. These diverse viewpoints inspired
us to investigate whether there was a difference in clinical
presentation between patients receiving SCIT on schedule, and those with
a treatment delay. Our results showed that clinical symptoms, medication
use, and quality of life were all within the normal range for SCIT
patients. In addition, we found no significant difference between
scheduled SCIT and delayed SCIT patients at the 1 year follow up period.
The result demonstrated again the long-term efficacy of SCIT in patients
with AR, even with a delay in therapy during the COVID-19 pandemic. This
information may encourage patients who have had to delay SCIT to
continue their treatment once the necessary social quarantine is over,
to recover their allergen-specific immune tolerance and modify the
progression of the disease.
Psychological disorder was also a notable element among patients
undergoing SCIT during the COVID-19 pandemic. In a report from China, up
to 35.1%, 20.1%, 18.2% of people showed depressive symptoms, the
symptoms of anxiety disorders, and a change in sleep quality during the
COVID-19 pandemic, respectively36. In our study, the
depressive symptoms in both scheduled and delayed SCIT patients at V0
was significantly higher than at V1, and exceeded the normal range at
both time points. Depressed patients reported an increase in symptoms,
reduced quality of life, and poor control of symptoms during the SCIT,
which was positively correlated with delayed treatment at V0. Our
findings may serve to remind allergists/immunologists that the
psychological burden on patients undergoing SCIT during the COVID-19
epidemic should be valued with the great attention, particularly with
regard to depressive symptoms37. The introduction of
patient education to relieve depression, should be included as part of
the management of SCIT, has previously been
suggested38.
Further developing the application of patient education and
telemedicine is an important part of
patient care during the unique circumstances brought by the COVID-19
pandemic39,40. Allergists/immunologists have been
urged to respond to this need by extending the long-standing trust
developed through years of face-to-face encounters into online
resources41. To assist patients with scheduled SCIT,
allergists/immunologists are recommended to post information on their
web site and social media channels regarding frequently asked questions
surrounding the COVID-19 outbreak, the changes to their SCIT practice
setting, the differences between acute AR and asthma symptoms, as well
as indications for COVID-19 testing. All of this can lower the
psychological distress for patients before they seek help at hospitals
or clinics42,43. The patients with delayed SCIT are
recommended to continue with follow-up visits online, and when possible,
home delivery and digital medicine services can be used to obtain
scheduled questionnaires and monitor drug
administration44,45. Local community organizations and
health services can also be utilized to assist patients who are treated
at home, and who may need support services to ensure optimal
care46-49. This unique period during the COVID-19
pandemic brings not only challenges, but also the opportunities to
update and improve the management of
SCIT.
Our RWE study provides valuable information on physical and mental
manifestations among patients undergoing delayed SCIT in a real-world
setting, which is essential to the evidence base required for treatment
practices50. Due to the limited design of the current
study we are not able to make conclusions regarding the underlying
mechanism of delayed SCIT immune responses. To investigate this further,
immunopathological features such as allergen-specific immunoglobulin E
(IgE) and immunoglobulin G4 antibodies, may be helpful.
In conclusion, we were able to confirm the long-term efficacy of SCIT in
patients with AR, even in patients with delayed treatment due to the
COVID-19 pandemic. In addition,
comorbid mild depressive symptoms, which were more common in patients
with not fully controlled SCIT, may require more attention.