LETTER TO THE EDITOR

We read with interest the article by Hasan, et al about a matched control study on the level of fatigue in 105 physicians with SARS-CoV-2 infection at least 6 weeks before the interview [Hasan, A. T. M. H. et al., 2024]. The fatigue severity scale (FSS) was significantly higher in SARS-CoV-2 infected physicians compared to healthy controls. Sixty-eight percent of physicians with a prior SARS-CoV-2 infection were in the highest FSS tertile compared to controls [Hasan, A. T. M. H. et al., 2024]. It was concluded that physicians with previous COVID-19 had higher FSS scores and a higher levels of fatigue than physicians without a previous COVID-19 infection but worked in the same hospital as the other doctors [Hasan, A. T. M. H. et al., 2024]. The study is compelling but some points require discussion.

The first point is that depression was not adequately assessed in any of the included patients. Since fatigue can be a key symptom of depression, it is imperative that depression has been sufficiently ruled out as a cause of high FSS values. How many of the doctors were regularly taking anti-depressive drugs?

The second point is that fatigue after a COVID-19 infection in physicians can also depend largely on the department in which the doctor worked. Ophthalmologists are likely to develop a different level of fatigue than doctors in the emergency room or intensive care unit (ICU). We should therefore know whether doctors in the COVID-19 group worked in the same departments or had more demanding jobs than doctors in the control group.

The third point is that diagnosing SARS-CoV-2 infection based on lung CT alone could be misleading, since the abnormalities found on lung-CT in COVID-19 patients could also indicate other causes, especially malignancies or infections other than COVID-19.

The fourth point is that it is not incomprehensible why asymptomatic cases were excluded [Hasan, A. T. M. H. et al., 2024]. We should know whether “asymptomatic” means we have no pulmonary symptoms or no symptoms at all. Because SARS-CoV-2 infection can manifest in extra-pulmonary organs, it may have been classified as asymptomatic even though the infection was atypical.

The fifth point is that the current medications that the included physicians regularly took were not included. Until we know whether COVID-19 patients were more likely to use sedatives, narcotics, hypnotics, antiepileptic drugs, neuroleptics, tranquilizer, alcohol or illicit drugs compared to controls, it is not possible to attribute increased FSS to COVID-19.

The sixth point is that it is not clear whether all patients included actually recovered completely and how many residual symptoms remained until the interview. In summary, the interesting study has limitations that put the results and their interpretation into perspective. Clarifying these weaknesses would strengthen the conclusions and could improve the study. Before fatigue in hospital physicians following a SARS-CoV-2 infection can be attributing solely to COVID-19, all differential causes must be thoroughly ruled out