Discussion
This is a descriptive study of patients referred to pediatric pulmonary
for Post-Acute Sequelae of SARS-CoV-2 infection (PASC), as defined by
the National Institute of Health and Care Excellence guidelines12. Most patients seen for protracted respiratory
symptoms following COVID-19 infection were not hospitalized and had mild
acute-COVID-19 symptomatology. Protracted respiratory symptoms
post-COVID-19 occurred in children as young as 4-years-old. In
comparable studies that included adults who did not require
hospitalization during initial COVID-19 illness, the most common
complaints were dyspnea and fatigue 5,8. In contrast,
in our pediatric study population, fatigue was only reported by four
patients (13.8%). Similar to our study in which we found that
exertional dyspnea was presented in almost all patients, Townsend et al.
reported that 62% of adult survivors of COVID-19 reported persistent
dyspnea and exertional limitation 75 days after their acute illness.
Interestingly, persistent dyspnea and exertional limitation were not
associated with initial disease severity in their study16.
In our study, although patients reported persistent exertional dyspnea,
cough and exercise intolerance, lung function was normal in most
children. Although objective measures of pulmonary function were
generally normal, including pulse oximetry, imaging and pulmonary
function testing, the six-minute walk test revealed exercise intolerance
and significant tachycardia in two-thirds of children tested. This
finding suggests that the six-minute walk test may be a low-cost and
simple way to evaluate children after COVID-19 and provide a
quantitative result that can be trended over time to assess improvement
or progression of disability.
We found an increased prevalence of atopy and obesity in our study
population that presented with prolonged post-COVID-19 respiratory
symptoms. According to the CDC, the most recent national asthma data
from 2019 suggests an asthma prevalence of 7% in children under 18
years 17. The asthma prevalence in our study
population was 37.9%, which is nearly five times higher than the
general population, and two-thirds were atopic. This may suggest that
asthma and atopy are risk factors for developing long COVID respiratory
symptoms in children and will require larger studies to confirm this
association. Obesity, defined as a BMI above the 95thpercentile, may also be linked to persistent symptoms after COVID-19.
Our study population has a higher rate of child obesity of 37.9%
compared to the local population rate of 20.3% 18;
however, this again may reflect study sample bias.
More studies are needed regarding effective management of patients with
post-COVID syndrome. Existing guidelines and rehabilitation programs are
directed at adult survivors of COVID-19 and recommend multidisciplinary
treatment approaches including pulmonary rehabilitation and physical
therapy 19. There are limited studies that report
improvement in persistent symptoms following vaccination20, but so far there are no studies looking at the
impact of vaccination in pediatric patients. Pacing and gradual return
to exercise may lessen exertional symptoms 19.
Additionally, the high prevalence of asthma and improvement following
bronchodilator administration observed in 47.6% of patients suggests
that there may be a role for bronchodilators and inhaled corticosteroids
in some pediatric patients.
Our population was recruited as a convenience sample and represents a
limitation to our study. Patients in this study were seen in a pediatric
pulmonary clinic and thus may be more motivated to seek out specialty
care or have fewer barriers to accessing care. It is likely that our
sample represents a small fraction of total cases of protracted COVID-19
symptoms in children within our catchment area, with the majority of
cases being seen by primary care physicians. The youngest subject in our
population was four years old, which may reflect the youngest age for
subjects to actively report symptoms, thus we cannot comment on whether
these protracted symptoms could be observed in even younger patients.
The burden of caring for COVID-19 survivors is expected to be
tremendous, and future medical and social interventions must consider
the late sequelae of SARS-CoV-2 infection. Even though children
experience less severe COVID-19 infections than adults, our study shows
that children can have significant long-term respiratory symptoms which
can impact quality of life in these children. Our study indicates that
ongoing respiratory morbidity can persist even in children with mild
acute-COVID-19 infection history and when impairments are not clearly
identified by available objective testing. This suggests that there will
be an increasing need to follow these children longitudinally to
determine the long-term consequences of COVID-19 infection on
respiratory health, as this information will have important implications
for public health surveillance, health resource allocation, clinical
research, and future treatments.