Impact of Pneumonia on Cognitive Aging: A Longitudinal Propensity-Matched Cohort Study.

BACKGROUND: Acute clinical events, such as pneumonia, may impact physical functionality but their effect on cognition and the possible duration of this effect remains to be quantified. This study investigated the impact of pneumonia on cognitive trajectories and dementia development in older people. METHODS: Data were obtained from 60+ years old individuals, who were assessed from 2001 to 2018 in the population-based SNAC-K study (Sweden). Participants were eligible if they were not institutionalized, had no dementia, and did not experience pneumonia 5 years prior to baseline (N = 2 063). A propensity score was derived to match 1:3 participants hospitalized with a diagnosis of pneumonia (N = 178), to nonexposed participants (N = 534). Mixed linear models were used to model cognitive decline. The hazard of dementia, clinically diagnosed by physicians following Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV, was estimated using Cox regression models. RESULTS: We found a transient impact of pneumonia on cognitive decline in the first 2.5 years (B = -0.94, 95% confidence interval [CI] -1.75, -0.15). The hazard ratio (HR) for dementia was not statistically significantly increased in pneumonia participants (HR = 1.17, 95%CI 0.82, 1.66). CONCLUSIONS: The transient impact of pneumonia on cognitive function suggests an increased need of health care for patients after a pneumonia-related hospitalization and reinforces the relevance of pneumonia prevention.

Cognitive impairment in patients with Neuro-Sjögren.

OBJECTIVE: Extraglandular neurological manifestations of Sjögren's syndrome are increasingly recognized, defining the disease entity of Neuro-Sjögren. Neuropsychological assessment of patients with Sjögren's syndrome has hitherto been performed on predominantly rheumatological cohorts. These studies revealed a wide variety of prevalence rates for cognitive impairment (22-80%), while variable cut-off criteria for detection of cognitive impairment were applied. Attentional functions have not yet been thoroughly investigated in these patients, although they clearly represent relevant aspects of cognitive functioning in daily life. METHODS: We therefore conducted extensive neuropsychological assessment based on two neuropsychological test batteries [i.e., the extended German version of the Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological Assessment Battery (CERAD-PLUS), and the test battery for attentional performance (TAP) as a well-established assessment of attentional functions in the German-speaking part of Europe]. RESULTS: Sixty-four patients with Neuro-Sjögren, who were treated at our university hospital between December 2016 and January 2019, were included. Evidence for the presence of cognitive impairment was found in 55% of patients with Neuro-Sjögren. The degree of cognitive impairment ranged from mild (38%) to severe (17%). Attentional and mnemonic subtests showed pronounced cognitive impairment in patients with Neuro-Sjögren. INTERPRETATION: Our results suggest that a substantial proportion of patients with Neuro-Sjögren suffer from cognitive impairment, putatively as a corollary of attentional deficits, which might exert adverse effects on occupational abilities, other cognitive functions, and social role functioning.

Computational Modeling for Neuropsychological Assessment of Bradyphrenia in Parkinson's Disease.

The neural mechanisms of cognitive dysfunctions in neurological diseases remain poorly understood. Here, we conjecture that this unsatisfying state-of-the-art is in part due to the non-specificity of the typical behavioral indicators for cognitive dysfunctions. Our study addresses the topic by advancing the assessment of cognitive dysfunctions through computational modeling. We investigate bradyphrenia in Parkinson's disease (PD) as an exemplary case of cognitive dysfunctions in neurological diseases. Our computational model conceptualizes trial-by-trial behavioral data as resulting from parallel cognitive and sensorimotor reinforcement learning. We assessed PD patients 'on' and 'off' their dopaminergic medication and matched healthy control (HC) participants on a computerized version of the Wisconsin Card Sorting Test. PD patients showed increased retention of learned cognitive information and decreased retention of learned sensorimotor information from previous trials in comparison to HC participants. Systemic dopamine replacement therapy did not remedy these cognitive dysfunctions in PD patients but incurred non-desirable side effects such as decreasing cognitive learning from positive feedback. Our results reveal novel insights into facets of bradyphrenia that are indiscernible by observable behavioral indicators of cognitive dysfunctions. We discuss how computational modeling may contribute to the advancement of future research on brain-behavior relationships and neuropsychological assessment.

A Meta-Analysis of Relationships between Measures of Wisconsin Card Sorting and Intelligence.

The Wisconsin Card Sorting Test (WCST) represents a widely utilized neuropsychological assessment technique for executive function. This meta-analysis examined the discriminant validity of the WCST for the assessment of mental shifting, considered as an essential subcomponent of executive functioning, against traditional psychometric intelligence tests. A systematic search was conducted, resulting in 72 neuropsychological samples for the meta-analysis of relationships between WCST scores and a variety of intelligence quotient (IQ) domains. The study revealed low to medium-sized correlations with IQ domains across all WCST scores that could be investigated. Verbal/crystallized IQ and performance/fluid IQ were indistinguishably associated with WCST scores. To conclude, the WCST assesses cognitive functions that might be partially separable from common conceptualizations of intelligence. More vigorous initiatives to validate putative indicators of executive function against intelligence are required.