Bariatric surgery and brain health: A longitudinal observational study investigating the effect of surgery on cognitive function and gray matter volume

Dietary modifications leading to weight loss have been suggested as a means to improve brain health. In morbid obesity, bariatric surgery (BARS)—including different procedures, such as vertical sleeve gastrectomy (VSG), gastric banding (GB), or Roux-en-Y gastric bypass (RYGB) surgery—is performed to induce rapid weight loss. Combining reduced food intake and malabsorption of nutrients, RYGB might be most effective, but requires life-long follow-up treatment. Here, we tested 40 patients before and six months after surgery (BARS group) using a neuropsychological test battery and compared them with a waiting list control group. Subsamples of both groups underwent structural MRI and were examined for differences between surgical procedures. No substantial differences between BARS and control group emerged with regard to cognition. However, larger gray matter volume in fronto-temporal brain areas accompanied by smaller volume in the ventral striatum was seen in the BARS group compared to controls. RYGB patients compared to patients with restrictive treatment alone (VSG/GB) had higher weight loss, but did not benefit more in cognitive outcomes. In sum, the data of our study suggest that BARS might lead to brain structure reorganization at long-term follow-up, while the type of surgical procedure does not differentially modulate cognitive performance

Weight loss reduces head motion: Re-visiting a major confound in neuroimaging

Head motion during magnetic resonance imaging (MRI) induces image artifacts that affect virtually every brain measure. In parallel, cross‐sectional observations indicate a correlation of head motion with age, psychiatric disease status and obesity, raising the possibility of a systematic artifact‐induced bias in neuroimaging outcomes in these conditions, due to the differences in head motion. Yet, a causal link between obesity and head motion has not been tested in an experimental design. Here, we show that a change in body mass index (BMI) (i.e., weight loss after bariatric surgery) systematically decreases head motion during MRI. In this setting, reduced imaging artifacts due to lower head motion might result in biased estimates of neural differences induced by changes in BMI. Overall, our finding urges the need to rigorously control for head motion during MRI to enable valid results of neuroimaging outcomes in populations that differ in head motion due to obesity or other conditions

Feasibility and first results of a group program to increase the frequency of cognitively stimulating leisure activities in people with mild cognitive impairment (AKTIVA–MCI)

AKTIVA-MCI is a program for patients with mild cognitive impairment (MCI) that aims to enhance participation in cognitively stimulating leisure activities. Participation in cognitively stimulating activities seems to be a potential strategy for people with MCI delaying cognitive decline for a while. In total, 35 MCI patients were enrolled in the pilot study of whom 29 completed the whole program (16 female, 71.1±7.5 years; Mini Mental Status Examination score: 28±2.2). Daily activity protocols were used to measure the frequency of participation in cognitively stimulating activities during the program (12 sessions). Additional standardized psychometric tests and questionnaires were used to assess cognition, mood, and subjective memory decline. Analyses of the daily activity protocols showed that during the intervention participants increased the frequency of several cognitively stimulating leisure activities. Comparison of pre-post data indicates no changes in cognitive status, mood, and subjective memory decline. These findings indicate that the program is suitable for patients with MCI

Altered paired associative stimulation-induced plasticity in NMDAR encephalitis

Objective: To determine whether neurophysiological mechanisms indicating cortical excitability, long-term potentiation (LTP)-like plasticity, GABAergic and glutamatergic function are altered in patients with anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis and whether they can be helpful as markers of diagnostic assessment, disease progression, and potentially therapy response. Methods: Neurophysiological characterizations of patients with NMDAR encephalitis (n = 34, mean age: 28 ± 11 years; 30 females) and age/gender-matched healthy controls (n = 27, 28.5 ± 10 years; 25 females) were performed using transcranial magnetic stimulation-derived protocols including resting motor threshold, recruitment curve, intracortical facilitation, short intracortical inhibition, and cortical silent period. Paired associative stimulation (PAS) was applied to assess LTP-like mechanisms which are mediated through NMDAR. Moreover, resting state functional connectivity was determined using functional magnetic resonance imaging. Results: PAS-induced plasticity differed significantly between groups (P = 0.0056). Cortical excitability, as assessed via motor-evoked potentials after PAS, decreased in patients, whereas it increased in controls indicating malfunctioning of NMDAR in encephalitis patients. Lower PAS-induced plasticity significantly correlated with the modified Rankin Scale (mRS) (r = −0.41; P = 0.0031) and was correlated with lower functional connectivity within the motor network in NMDAR encephalitis patients (P < 0.001, uncorrected). Other neurophysiological parameters were not significantly different between groups. Follow-up assessments were available in six patients and demonstrated parallel improvement of PAS-induced plasticity and mRS. Interpretation: Assessment of PAS-induced plasticity may help to determine NMDAR dysfunction and disease severity in NMDAR encephalitis, and might even aid as a sensitive, noninvasive, and well-tolerated “electrophysiological biomarker” to monitor therapy response in the future.Clinical Trial Registration: ClinicalTrials.gov: Identifier: NCT0186557

Impact of COVID-19 emergency on the psychological well-being of susceptible individuals

The current pandemic has exerted an unprecedented psychological impact on the world population, and its effects on mental health are a growing concern. The present study aims to evaluate psychological well-being (PWB) during the COVID-19 crisis in university workers with one or more diseases likely to increase the risk of severe outcomes in the event of SARS-CoV-2 infection, defined as susceptible. 210 susceptible employees of an Italian University (aged 25-71 years) were recruited during the COVID-19 second wave (October-December 2020). A group comprising 90 healthy university employees (aged 26-69 years) was also recruited. The self-report Psychological General Well Being Index (PGWBI) was used to assess global PWB and the influence on six sub-domains: anxiety, depressed mood, positive well-being, self-control, general health, and vitality. We applied non-linear dimension-reduction techniques and regression methods to 45 variables in order to assess the main demographic, occupational, and general-health-related factors predicting PWB during the COVID-19 crisis. PGWBI score was higher in susceptible than in healthy workers, both as total score (mean 77.8 vs 71.3) and across almost all subscales. Age and jobs involving high social interaction before the pandemic were inversely associated with the PWB total score, general health, and self-control subscores. The current data suggest no decline in PWB during the second wave of COVID-19 health emergency in susceptible individuals of working age. Critically, higher risk for mental-health issues appears to be inversely related to age, particularly among individuals deprived of their previous level of social interaction at work

Feasibility and first results of a group program to increase the frequency of cognitively stimulating leisure activities in people with mild cognitive impairment (AKTIVA–MCI)

AKTIVA-MCI is a program for patients with mild cognitive impairment (MCI) that aims to enhance participation in cognitively stimulating leisure activities. Participation in cognitively stimulating activities seems to be a potential strategy for people with MCI delaying cognitive decline for a while. In total, 35 MCI patients were enrolled in the pilot study of whom 29 completed the whole program (16 female, 71.1±7.5 years; Mini Mental Status Examination score: 28±2.2). Daily activity protocols were used to measure the frequency of participation in cognitively stimulating activities during the program (12 sessions). Additional standardized psychometric tests and questionnaires were used to assess cognition, mood, and subjective memory decline. Analyses of the daily activity protocols showed that during the intervention participants increased the frequency of several cognitively stimulating leisure activities. Comparison of pre-post data indicates no changes in cognitive status, mood, and subjective memory decline. These findings indicate that the program is suitable for patients with MCI

Transcranial direct current stimulation over multiple days improves learning and maintenance of a novel vocabulary

Introduction: Recently, growing interest emerged in the enhancement of human potential by means of non-invasive brain stimulation. In particular, anodal transcranial direct current stimulation (atDCS) has been shown to exert beneficial effects on motor and higher cognitive functions. However, the majority of transcranial direct current stimulation (tDCS) studies have assessed effects of single stimulation sessions that are mediated by transient neural modulation. Studies assessing the impact of multiple stimulation sessions on learning that may induce long-lasting behavioural and neural changes are scarce and have not yet been accomplished in the language domain in healthy individuals

FCET2EC (From controlled experimental trial to = 2 everyday communication): How effective is intensive integrative therapy for stroke-induced chronic aphasia under routine clinical conditions? A study protocol for a randomized controlled trial

Background: Therapy guidelines recommend speech and language therapy (SLT) as the “gold standard” for aphasia treatment. Treatment intensity (i.e., ≥5 hours of SLT per week) is a key predictor of SLT outcome. The scientific evidence to support the efficacy of SLT is unsatisfactory to date given the lack of randomized controlled trials (RCT), particularly with respect to chronic aphasia (lasting for >6 months after initial stroke). This randomized waiting list-controlled multi-centre trial examines whether intensive integrative language therapy provided in routine in- and outpatient clinical settings is effective in improving everyday communication in chronic post-stroke aphasia. Methods/Design: Participants are men and women aged 18 to 70 years, at least 6 months post an ischemic or haemorrhagic stroke resulting in persisting language impairment (i.e., chronic aphasia); 220 patients will be screened for participation, with the goal of including at least 126 patients during the 26-month recruitment period. Basic language production and comprehension abilities need to be preserved (as assessed by the Aachen Aphasia Test).Therapy consists of language-systematic and communicative-pragmatic exercises for at least 2 hours/day and at least 10 hours/week, plus at least 1 hour self-administered training per day, for at least three weeks. Contents of therapy are adapted to patients’ individual impairment profiles.Prior to and immediately following the therapy/waiting period, patients’ individual language abilities are assessed via primary and secondary outcome measures. The primary (blinded) outcome measure is the A-scale (informational content, or 'understandability’, of the message) of the Amsterdam-Nijmegen Everyday Language Test (ANELT), a standardized measure of functional communication ability. Secondary (unblinded) outcome measures are language-systematic and communicative-pragmatic language screenings and questionnaires assessing life quality as viewed by the patient as well as a relative.The primary analysis tests for differences between the therapy group and an untreated (waiting list) control group with respect to pre- versus post 3-week-therapy (or waiting period, respectively) scores on the ANELT A-scale. Statistical between-group comparisons of primary and secondary outcome measures will be conducted in intention-to-treat analyses. Long-term stability of treatment effects will be assessed six months post intensive SLT (primary and secondary endpoints)

Impact of Resveratrol on Glucose Control, Hippocampal Structure and Connectivity, and Memory Performance in Patients with Mild Cognitive Impairment

In healthy older adults, resveratrol supplementation has been shown to improve long-term glucose control, resting-state functional connectivity (RSFC) of the hippocampus, and memory function. Here, we aimed to investigate if these beneficial effects extend to individuals at high-risk for dementia, i.e., patients with mild cognitive impairment (MCI). In a randomized, double-blind interventional study, 40 well-characterized patients with MCI (21 females; 50–80 years) completed 26 weeks of resveratrol (200 mg/d; n = 18) or placebo (1,015 mg/d olive oil; n = 22) intake. Serum levels of glucose, glycated hemoglobin A1c and insulin were determined before and after intervention. Moreover, cerebral magnetic resonance imaging (MRI) (3T) (n = 14 vs. 16) was conducted to analyze hippocampus volume, microstructure and RSFC, and neuropsychological testing was conducted to assess learning and memory (primary endpoint) at both time points. In comparison to the control group, resveratrol supplementation resulted in lower glycated hemoglobin A1c concentration with a moderate effect size (ANOVARM p = 0.059, Cohen's d = 0.66), higher RSFC between right anterior hippocampus and right angular cortex (p < 0.001), and led to a moderate preservation of left anterior hippocampus volume (ANOVARM p = 0.061, Cohen's d = 0.68). No significant differences in memory performance emerged between groups. This proof-of-concept study indicates for the first-time that resveratrol intake may reduce glycated hemoglobin A1c, preserves hippocampus volume, and improves hippocampus RSFC in at-risk patients for dementia. Larger trials with longer intervention time should now determine if these benefits can be validated and extended to cognitive function