Background COVID-19 sequelae are poorly defined with an ambiguous pathophysiology. Persistent sequelae could have global, public health and societal ramifications. We aimed to describe sequelae presenting more than six months after COVID-19 in non-hospitalized young adults.
Methods A prospective, longitudinal cohort study followed-up on young Swiss Armed Forces (SAF) personnel. The comprehensive test battery was administered during a single full day of testing at the University of Zürich. It quantified the impact of SARS-CoV-2 infection on cardiovascular, pulmonary, neurological, renal, ophthalmological, male reproductive, psychological, and general health in addition to laboratory parameters.
Results We included 501 participants (5.6% females) with a median age of 21 years (range 19-29). Cases of previous COVID -19 (>6 months (mean 10 months) since diagnosis, n=177) were compared with never infected controls (n=248). We also included more recent COVID-19 cases (≤6 months, n=19) and asymptomatically infected individuals (n=49). We found a significant trend towards metabolic disorders, higher Body Mass Index (BMI) (p=0.03), lower aerobic threshold (p=0.007), higher blood cholesterol (p<0.001) and low-density lipoprotein LDL levels (p<0.001) in participants> 6 months post Covid-19 when compared to controls. There were no significant differences in psychosocial questionnaire scores, ophthalmological outcomes, sperm quality or motility between controls and those infected more than 6 months previously with SARS-CoV-2.
Conclusions Young, previously healthy, individuals largely recover from mild infection and the multi-system impact of the infection is less that seen in older or hospitalized patients. These results may be extrapolated to health-care workers and other young workforce adults. However, the constellation of higher body mass index, dyslipidemia and lower physical endurance 6 months post COVID-19 is suggestive of a higher risk of developing metabolic disorders and possible cardiovascular complications. These findings will guide investigation and follow-up management.
### Competing Interest Statement
The authors have declared no competing interest.
### Funding Statement
This study was funded by the Swiss Armed Forces
### Author Declarations
I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.
The details of the IRB/oversight body that provided approval or exemption for the research described are given below:
This study was approved by the Swiss Zurich Cantonal Ethics Committee (BASEC-Nr. 2021-00256).
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The data produced in the present study may be available upon reasonable request to the authors