AUTHOR=Fernández-de-las-Peñas César , Cancela-Cilleruelo Ignacio , Rodríguez-Jiménez Jorge , Arias-Navalón José A. , Martín-Guerrero José D. , Pellicer-Valero Oscar J. , Arendt-Nielsen Lars , Cigarán-Méndez Margarita 

TITLE=Trajectory of post-COVID brain fog, memory loss, and concentration loss in previously hospitalized COVID-19 survivors: the LONG-COVID-EXP multicenter study

JOURNAL=Frontiers in Human Neuroscience

VOLUME=17

YEAR=2023

URL=https://www.frontiersin.org/journals/human-neuroscience/articles/10.3389/fnhum.2023.1259660

DOI=10.3389/fnhum.2023.1259660

ISSN=1662-5161

ABSTRACT=<sec id="sec1"><title>Objective</title><p>This study aimed to apply Sankey plots and exponential bar plots for visualizing the trajectory of post-COVID brain fog, memory loss, and concentration loss in a cohort of previously hospitalized COVID-19 survivors.</p></sec><sec id="sec2"><title>Methods</title><p>A sample of 1,266 previously hospitalized patients due to COVID-19 during the first wave of the pandemic were assessed at 8.4 (T1), 13.2 (T2), and 18.3 (T3) months after hospital discharge. They were asked about the presence of the following self-reported cognitive symptoms: brain fog (defined as self-perception of sluggish or fuzzy thinking), memory loss (defined as self-perception of unusual forgetfulness), and concentration loss (defined as self-perception of not being able to maintain attention). We asked about symptoms that individuals had not experienced previously, and they attributed them to the acute infection. Clinical and hospitalization data were collected from hospital medical records.</p></sec><sec id="sec3"><title>Results</title><p>The Sankey plots revealed that the prevalence of post-COVID brain fog was 8.37% (<italic>n</italic> = 106) at T1, 4.7% (<italic>n</italic> = 60) at T2, and 5.1% (<italic>n</italic> = 65) at T3, whereas the prevalence of post-COVID memory loss was 14.9% (<italic>n</italic> = 189) at T1, 11.4% (<italic>n</italic> = 145) at T2, and 12.12% (<italic>n</italic> = 154) at T3. Finally, the prevalence of post-COVID concentration loss decreased from 6.86% (<italic>n</italic> = 87) at T1, to 4.78% (<italic>n</italic> = 60) at T2, and to 2.63% (<italic>n</italic> = 33) at T3. The recovery exponential curves show a decreasing trend, indicating that these post-COVID cognitive symptoms recovered in the following years after discharge. The regression models did not reveal any medical record data associated with post-COVID brain fog, memory loss, or concentration loss in the long term.</p></sec><sec id="sec4"><title>Conclusion</title><p>The use of Sankey plots shows a fluctuating evolution of post-COVID brain fog, memory loss, or concentration loss during the first years after the infection. In addition, exponential bar plots revealed a decrease in the prevalence of these symptoms during the first years after hospital discharge. No risk factors were identified in this cohort.</p></sec>