The Clinical Neuropsychologist

Objective: Objective cognitive impairment has been shown in a minority of hospitalized COVID-19 patients, and longitudinal studies with a relatively long follow-up duration are scarce. We sought to investigate the presence and long-term change of objectivecognitive functioning. Method: Forty-six initially hospitalized (18 ± 19 days) COVID-19 survivors (male/female: 30/16; age: 61 ± 11) underwent extensive neuropsychological assessment (including performance validity) approximately 1 (T1) and 2.5 years (T2) post-infection. Cognitive domains assessed were: memory, attention, executive functioning, processing speed, and language (n = 14(sub)tests). We used normative data to derive age, sex, and education-adjusted T-scores (T ≤ 35 [≤–1.5SD], deficit cut-off). Repeated measures AN(C)OVAs were used to investigate cognitivefunctioning over time. Results: Mean neuropsychological performance (n = 14 tests) was within normal range at both timepoints, and number of individuals with objective cognitive deficits ranged from 0–20% (T1), and 2–22% (T2). Number of subjective cognitive complaints remained unchanged. A minority (17%) showed objective cognitive deficits on ≥2 tests at both 1 and 2.5 years post-infection, but not consistently within one cognitive domain. Longitudinal analyses on the total sample showed improvement inperformance over time on phonemic fluency (p<.001), but stable cognitive performance on all other tests, independent of prior comorbidities, subjective cognitive complaints, depressive symptoms, and ICU admission. Conclusions: There were no consistent objective cognitive deficits or major cognitive disorders years after SARS-CoV-2 infection in the majority of cases. Neuropsychological functioning remained essentially unchanged over time. Future larger longitudinal studies are necessary to unravel COVID-19-related cognitive phenotypes of persisting deficits and how these can be modulated.

Objective: The Trail Making Test (TMT) is a widely used neuropsy-chological tool for assessing executive functions. This study aimed to establish regression-based normative data for TMT performance in a Turkish population aged 18-80, accounting for the effects of age, education, and sex on both basic (TMT A and TMT B) and derived scores (TMT B-A and TMT B/A). Method: A total of 462 participants were recruited, with 409 included in the final analysis after applying exclusion criteria. Participants completed the international version of the TMT. Pearson correlation analyses and multiple linear regression models assessed relationships between TMT scores and demographic variables. Education was treated as a continuous variable, and regression-based norms were developed for all TMT scores. Results: Age and education were significant predic-tors of TMT performance. Age primarily affected TMT A scores, while education was the strongest predictor for TMT B, TMT B-A, and TMT B/A scores. The regression models explained 36-38% of the variance in basic scores and 6-24% in derived scores. Women performed better than men on the TMT B/A ratio score, but overall , sex had a less pronounced effect than age and education. Conclusions: This study provides the first regression-based norma-tive data for the TMT in a Turkish population. These norms are crucial for improving the accuracy of neuropsychological assessments in Turkey and facilitating cross-cultural comparisons in cognitive research. The findings emphasize the importance of adjusting for demographic factors in clinical and research settings to ensure precise evaluations of cognitive functioning.