Central Nervous System Manifestations of COVID-19: A Critical Review and Proposed Research Agenda.

OBJECTIVE: On March 11, 2020, the World Health Organization declared an outbreak of a new viral entity, coronavirus 2019 (COVID-19), to be a worldwide pandemic. The characteristics of this virus, as well as its short- and long-term implications, are not yet well understood. The objective of the current paper was to provide a critical review of the emerging literature on COVID-19 and its implications for neurological, neuropsychiatric, and cognitive functioning. METHOD: A critical review of recently published empirical research, case studies, and reviews pertaining to central nervous system (CNS) complications of COVID-19 was conducted by searching PubMed, PubMed Central, Google Scholar, and bioRxiv. RESULTS: After considering the available literature, areas thought to be most pertinent to clinical and research neuropsychologists, including CNS manifestations, neurologic symptoms/syndromes, neuroimaging, and potential long-term implications of COVID-19 infection, were reviewed. CONCLUSION: Once thought to be merely a respiratory virus, the scientific and medical communities have realized COVID-19 to have broader effects on renal, vascular, and neurological body systems. The question of cognitive deficits is not yet well studied, but neuropsychologists will undoubtedly play an important role in the years to come.

Anticholinergic Medication Burden and Cognitive Subtypes in Parkinson's Disease without Dementia.

OBJECTIVE: Cognitive changes are heterogeneous in Parkinson's disease (PD). This study compared whether anticholinergic burden drives differences in cognitive domain performance and empirically-derived PD-cognitive phenotypes. METHOD: A retrospective chart review contained participants (n = 493) who had idiopathic PD without dementia. Participants' medications were scored (0-3) and summed based on the anticholinergic cognitive burden scale (ACBS). We examined the ACBS' relationship to five cognitive domain composites (normative z-scores) and three (K-means clustering based) cognitive phenotypes: cognitively intact, low executive function (EF), and predominately impaired EF/memory. Analyses included Spearman correlations, analysis of covariance, and Pearson chi-squared test. RESULTS: Overall, phenotypes did not differ in anticholinergic burden, and (after false-discovery-rate corrections) no cognitive domains related. When comparing those above and below the clinically relevant ACBS cutoff (i.e., score ≥3), no significant phenotype or domain differences were found. CONCLUSIONS: Anticholinergic medication usage did not drive cognitive performance in a large clinical sample of idiopathic PD without dementia.