A promising cognitive screener in multiple sclerosis: The NIH toolbox cognition battery concords with gold standard neuropsychological measures

Fluid Cognition Among Individuals With Systemic Lupus Erythematosus

OBJECTIVE

We sought to describe fluid cognition and its correlates among individuals with systemic lupus erythematosus (SLE).

METHODS

Participants (n = 199) were recruited from a population-based cohort for a single study visit (October 2019 to May 2022). Fluid cognition was measured via the National Institutes of Health Toolbox Fluid Cognition Battery (including episodic memory, working memory, attention and inhibitory control, processing speed, and cognitive flexibility domains) and expressed as age-corrected standard scores (mean 100, SD 15). Potential impairment was defined as a standard score >1.5 SD below the mean. Descriptive statistics were calculated and associations of various participant characteristics with the potential fluid cognition impairment were assessed with multivariable logistic regression.

RESULTS

Participants' mean age was 46.1 years; most were female (87.4%), Black (86.4%), and non-Hispanic (95.0%). The mean overall fluid cognition score was 87.2; of the individual domains, the participants' mean score was lowest on attention and inhibitory control (82.0). Working status (odds ratio [OR] 0.30, 95% confidence interval [CI] 0.14-0.64) and higher self-reported physical functioning (OR 0.46, 95% CI 0.28-0.75) and physical performance (OR 0.72, 95% CI 0.59-0.87) were associated with lower odds of fluid cognition impairment; lower educational attainment was associated with higher odds (OR 3.82, 95% CI 1.67-8.75). Self-reported forgetfulness, neuropsychiatric damage, and depressive symptoms were not statistically significantly associated with potential impairment.

CONCLUSION

Fluid cognition and, particularly, attention and inhibitory control were low in those with SLE relative to the general US population. Working status, higher physical functioning and performance, and higher educational attainment were associated with lower prevalence of potential impairment. Future work is needed to develop and implement interventions to help support cognition in individuals with SLE.

Edge-Community Entropy Is a Novel Neural Correlate of Aging and Moderator of Fluid Cognition

Decreased neuronal specificity of the brain in response to cognitive demands (i.e., neural dedifferentiation) has been implicated in age-related cognitive decline. Investigations into functional connectivity analogs of these processes have focused primarily on measuring segregation of nonoverlapping networks at rest. Here, we used an edge-centric network approach to derive entropy, a measure of specialization, from spatially overlapping communities during cognitive task fMRI. Using Human Connectome Project Lifespan data (713 participants, 36-100 years old, 55.7% female), we characterized a pattern of nodal despecialization differentially affecting the medial temporal lobe and limbic, visual, and subcortical systems. At the whole-brain level, global entropy moderated declines in fluid cognition across the lifespan and uniquely covaried with age when controlling for the network segregation metric modularity. Importantly, relationships between both metrics (entropy and modularity) and fluid cognition were age dependent, although entropy's relationship with cognition was specific to older adults. These results suggest entropy is a potentially important metric for examining how neurological processes in aging affect functional specialization at the nodal, network, and whole-brain level.

Utility of the NIH Toolbox Cognition Battery in middle to older aged adults with longstanding type 1 diabetes: The DCCT/EDIC study

Objective: Adults with type 1 diabetes (T1D) face an increased risk for cognitive decline and dementia. Diabetes-related and vascular risk factors have been linked to cognitive decline using detailed neuropsychological testing; however, it is unclear if cognitive screening batteries can detect cognitive changes associated with aging in T1D. Method: 1,049 participants with T1D (median age 59 years; range 43-74) from the Diabetes Control and Complications Trial (DCCT), and the follow-up Epidemiology of Diabetes Interventions and Complications (EDIC) study, completed the NIH Toolbox Cognition Battery (NIHTB-C) and Montreal Cognitive Assessment (MoCA). Neuropsychological assessments, depression, glycated hemoglobin levels (HbA1c), severe hypoglycemia, T1D complications, and vascular risk factors were assessed repeatedly over 32 years to determine associations with current NIHTB-C performance. Available cognitive data was clinically adjudicated to determine cognitive impairment status. Results: NIHTB-C scores had moderate associations (r = 0.36-0.53) with concurrently administered neuropsychological tests. In multivariate models, prior severe hypoglycemic episodes, depression symptoms, nephropathy, lower BMI, and higher HbA1c and LDL cholesterol were associated with poorer NIHTB-C Fluid Cognition Composite scores. The NIHTB-C adequately detected adjudicated cognitive impairment (Area Under the Curve = 0.86; optimal cut score ≤90). The MoCA performed similarly (Area Under the Curve = 0.83; optimal cut score ≤25). Conclusions: The NIHTB-C is sensitive to the cognitive effects of diabetes-related and vascular risk factors, correlated with neuropsychological testing, and accurately detects adjudicated cognitive impairment. These data support its use as a screening test in middle to older aged adults with T1D to determine if referral for detailed neuropsychological assessment is needed.

The relationship between depression and cognitive performance in multiple sclerosis: A meta-analysis

Objective: Studies on the relationship between depression and cognition on patients with multiple sclerosis (MS) are inconsistent and it is not clear whether higher depression levels are associated with impairment of specific cognitive domains or processes. This meta-analytic study aimed at evaluating the possible association between depressive symptomatology and performance on cognitive tests assessing several cognitive domains (global cognition, attention, processing speed, verbal, spatial and working memory, verbal fluency, inhibitory control, set-shifting) in individuals living with MS. Method: The literature search on three electronic databases yielded 5402 studies (4333 after the duplicates removal); after the evaluation of titles, abstracts full-text articles, 37 studies were included in the meta-analytic study. A random-effect model meta-analysis was performed and mean weighted effect sizes (ESs) were calculated using Hedges' g. Results: Small ESs were found for the relationship between depression and verbal memory (g = 0.25, p < 0.001), spatial memory (g = 0.23, p < 0.001), verbal fluency (g = 0.26, p < 0.001), and inhibitory control (g = 0.32, p = 0.003). Medium ESs were found for the relationship between depression and global cognition (g = 0.46, p < 0.001), attention (g = 0.43, p < 0.001), processing speed (g = 0.47, p < 0.001) and working memory (g = 0.38, p = 0.037). The relationship between set-shifting abilities and depression was not significant (g = 0.39, p = 0.095). Conclusions: Results suggest that patients with MS and higher levels of depressive symptomatology may also show more difficulties in several aspects of cognition, especially those needed to retain, respond, and process information in one's environment, and to those needed be adequately stimulated in processing relevant information.

Predictors of performance and perceived fatigability in people with multiple sclerosis

BACKGROUND AND OBJECTIVE

Fatigability is a distinct construct from fatigue that has been reported to contribute to activity limitations in people with multiple sclerosis (PwMS). Identifying predictors of performance and perceived fatigability may guide the development of interventions to mitigate fatigability. This study investigated predictors of performance and perceived fatigability among PwMS.

METHODS

PwMS (N = 51) completed self-report measures of demographics, clinical history, symptoms severity (Modified Fatigue Impact Scale), and functioning (PROMIS Physical Function and PROMIS Cognitive Function Abilities). Performance fatigability measures included Ambulatory Fatigue Index (AFI), Deceleration Index (DI), and Distance Walking Index (DWI). Perceived fatigability measures included Pittsburgh Fatigability Scale (PFS), Perceived Physical Exertion, and Perceived Fatigue Intensity. Performance and perceived fatigability measures were calculated based on the Timed 25-Foot Walk Test and the 6-Minute Walk Test.

RESULTS

Multivariable linear regression analyses indicated that PROMIS Cognitive Function was a significant independent predictor of performance fatigability measured with AFI (β = -0.515, p = 0.007), DI (β = -0.511, p = 0.008), and DWI (β = -0.516, p = 0.007). Regarding perceived fatigability, PROMIS Pain Intensity predicted Perceived Fatigue Intensity (β = 0.325, p = 0.035). PROMIS Physical Function predicted PFS Mental fatigability (β = -0.503, p < 0.001). PROMIS Physical Function (β = -0.619, p < 0.001) and Cognitive Function (β = -0.249, p = 0.037) predicted PFS Physical fatigability.

CONCLUSIONS

Preliminary findings suggest that self-reported functioning levels, including physical and perceived cognitive function, are potential predictors of performance and perceived fatigability in MS. Notably, perceived fatigue impact showed no association with performance or perceived fatigability. Future studies are warranted to confirm and extend our findings.

Long non-coding RNAs BACE1-AS and BC200 in multiple sclerosis and their relation to cognitive function: A gene expression analysis

Cognitive impairment is a common and debilitating feature of multiple sclerosis (MS), and the dysregulation of synaptic plasticity is one of its direct causes. Long non-coding RNAs (lncRNAs) have been shown to play a role in synaptic plasticity, but their role in cognitive impairment in MS has not been fully explored. In this study, using quantitative real-time PCR, we examined the relative expression of two specific lncRNAs, BACE1-AS and BC200, in the serum of two cohorts of MS patients with and without cognitive impairment. Both lncRNAs were overexpressed in both cognitively impaired and non-cognitively impaired MS patients, with consistently higher levels in the cohort with cognitive impairment. We also found a strong positive correlation between the expression levels of these two lncRNAs. Notably, BACE1-AS was consistently higher in the remitting cases of both relapsing-remitting MS (RRMS) and secondary progressive MS (SPMS) groups than in the respective relapse cases of the same subtype, with the SPMS-Remitting group of cognitively impaired MS patients showing the highest expression of BACE1-AS among all MS groups. Additionally, we observed that the primary progressive MS (PPMS) group had the highest expression of BC200 in both cohorts of MS. Furthermore, we developed a model called Neuro_Lnc-2, which showed better diagnostic performance than either BACE1-AS or BC200 alone in predicting MS. Our findings suggest that these two lncRNAs may have a significant impact on the pathogenesis of the progressive types of MS and on the cognitive function of the patients. Future research is required to confirm these findings.