We read with great interest the comments in the letter by N. Mitchell regarding the prediction of neurological symptoms of Covid-19 by using the age of the study participants. Indeed, we are grateful for the valuable insights into a still scantly explored aspect of the disease.
Our study [1] was intended to analyze the spectrum of neurological symptoms and their possible predictive value for the course of the disease, and we were able to document the duration but not the severity of neurological symptoms.
Statistical data published by the Austrian Federal Ministry of the Interior [2] shows that in the period of our study, March 13th – April 14th 2020, the mean age (56,7 years) of SARS-CoV-2 positive patients in Austria was much higher compared to the time before and after our study. For example, the mean age of Sars-CoV-2 patients in calendar week 34 was 31.5, and in week 42 40.6 years. These data may provide explanation of the older age of participants in our study.
The more frequent occurrence of anosmia in younger patients described by Lechien et al. [3] may also be in line with our results showing a negative correlation with age (p = .096) in out- patients. Further trends of increased frequency in younger patients were observed for the symptoms myalgia (p = .052) and headache (p = .055), although not significant.
Due to the increasing prevalence of younger patients and the changing pattern of symptoms and course of the disease due to the emerging variants, further studies and development of databases will be required in order to enable an effective analysis regarding early predictors of the course of Covid-19 disease.
References
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- 2.https://data.gv.at/covid-19. Österreichisches Covid-19 Open Data Informationsportal.
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