Impairment of functional integration of the default mode network correlates with cognitive outcome at three months after stroke.

Resting-state studies conducted with stroke patients are scarce. The study of brain activity and connectivity at rest provides a unique opportunity for the investigation of brain rewiring after stroke and plasticity changes. This study sought to identify dynamic changes in the functional organization of the default mode network (DMN) of stroke patients at three months after stroke. Eleven patients (eight male and three female; age range: 48-72) with right cortical and subcortical ischemic infarctions and 17 controls (eleven males and six females; age range: 57-69) were assessed by neurological and neuropsychological examinations and scanned with resting-state functional magnetic ressonance imaging. First, we explored group differences in functional activity within the DMN by means of probabilistic independent component analysis followed by a dual regression approach. Second, we estimated functional connectivity between 11 DMN nodes both locally by means of seed-based connectivity analysis, as well as globally by means of graph-computation analysis. We found that patients had greater DMN activity in the left precuneus and the left anterior cingulate gyrus when compared with healthy controls (P < 0.05 family-wise error corrected). Seed-based connectivity analysis showed that stroke patients had significant impairment (P = 0.014; threshold = 2.00) in the connectivity between the following five DMN nodes: left superior frontal gyrus (lSFG) and posterior cingulate cortex (t = 2.01); left parahippocampal gyrus and right superior frontal gyrus (t = 2.11); left parahippocampal gyrus and lSFG (t = 2.39); right parietal and lSFG (t = 2.29). Finally, mean path length obtained from graph-computation analysis showed positive correlations with semantic fluency test (r(s) = 0.454; P = 0.023), phonetic fluency test (r(s) = 0.523; P = 0.007) and the mini mental state examination (r(s) = 0.528; P = 0.007). In conclusion, the ability to regulate activity of the DMN appears to be a central part of normal brain function in stroke patients. Our study expands the understanding of the changes occurring in the brain after stroke providing a new avenue for investigating lesion-induced network plasticity.

Assessing adipokines as potential biomarkers of dementia, Alzheimer's disease, and mild cognitive impairment: A systematic review and meta-analysis.

Midlife obesity and late-life weight loss confer a greater risk for developing dementia and Alzheimer's disease (AD), but the exact mechanisms behind this phenomenon are currently unknown. The answer could lie on the involvement of gastrointestinal factors, such as adipokines (e.g., leptin, adiponectin, and resistin) and ghrelin. In this context, we conducted a pre-registered systematic review and meta-analysis of 42 cross-sectional and 13 longitudinal studies targeting the associations between leptin, adiponectin, resistin, and ghrelin and the prevalence of general dementia, AD, and mild cognitive impairment (MCI). We also examined the relationship between the four gastrointestinal factors and neurocognitive outcomes and AD-related cerebrospinal fluid biomarkers. Patients with AD had lower blood leptin and higher resistin levels than cognitively normal participants. Lower leptin and higher resistin were associated with higher degree of cognitive impairment. Additionally, lower late-life leptin levels might be associated with higher prospective risk of dementia and AD, although more studies are needed to corroborate this. Results in ghrelin and adiponectin were not conclusive, with age, sex distribution, obesity, and severity of dementia seemingly acting as moderators across several analyses. Our work might contribute to the identification of new preclinical blood markers of MCI and AD.

Obesity and Gray Matter Volume Assessed by Neuroimaging: A Systematic Review.

Obesity has become a major public and individual health problem due to its high worldwide prevalence and its relation with comorbid conditions. According to previous studies, obesity is related to an increased risk of cognitive impairment and dementia. This systematic review aims to further examine the present state of the art about the association between obesity and gray matter volume (GMV) as assessed by magnetic resonance imaging (MRI). A search was conducted in Pubmed, SCOPUS and Cochrane of those studies released before 1 February 2021 including MRIs to assess the GMVs in obese participants. From this search, 1420 results were obtained, and 34 publications were finally included. Obesity was mainly measured by the body mass index, although other common types of evaluations were used (e.g., waist circumference, waist-to-hip ratio and plasma leptin levels). The selected neuroimaging analysis methods were voxel-based morphometry (VBM) and cortical thickness (CT), finding 21 and 13 publications, respectively. There were 30 cross-sectional and 2 prospective longitudinal studies, and 2 articles had both cross-sectional and longitudinal designs. Most studies showed a negative association between obesity and GMV. This would have important public health implications, as obesity prevention could avoid a potential risk of GMV reductions, cognitive impairment and dementia.

Psychometric Properties of the PDRQ-9 in Cancer Patients: Patient-Doctor Relationship Questionnaire.

BACKGROUND: The patient-doctor relationship is an important concept in health care. The aim of this study was to evaluate the psychometric properties, convergent validity, and factorial invariance of the Patient-Doctor Relationship Questionnaire (PDRQ-9). METHOD: Confirmatory factor analysis was conducted to explore the scale's dimensionality and test for strong measurement invariance across sex, age, and tumor site in a prospective, multicenter cohort of 560 patients who completed the PDRQ-9, Health-related Quality of Life Questionnaire (EORTC-QLQ-C30), and Brief Symptom Inventory (BSI) scales. RESULTS: The data supported a unidimensional structure. Thresholds and factor loadings could be constrained to be invariant across sex, age, and tumor site, indicating strong measurement invariance. Scores derived from the unidimensional structure exhibited satisfactory degrees of reliability and determinacy. Evidence of convergent validity was supported by modest positive correlations with functional (p<.001) and global quality-of-life (p<.001) and negative correlations with psychological distress (p<.001). Low satisfaction with the oncologist was associated with anxiety (p=.006), and depression (p=.004). CONCLUSIONS: The PDRQ-9 is a suitable, valid instrument for assessing the quality of patient-doctor relationships in cancer patients.

Psychometric properties of Spanish version of the Mini-Mental Adjustment to Cancer Scale.

BACKGROUND/OBJECTIVE: The aim of the study was to examine the factor structure and psychometric properties of the Spanish version of the Mini-Mental Adjustment to Cancer Scale (Mini-MAC) in a large sample of patients with non-metastatic, resected cancer. METHODS: Prospective, observational, multicenter study for which 914 patients were recruited from 15 Spanish hospitals. Exploratory and confirmatory factor analyses, validity and reliability analyses were conducted. RESULTS: Factor-analytic results indicated a 4-factor structure of the Spanish version of the Mini-MAC. Three subscales have psychometric properties similar to those of Helplessness, Anxious preoccupation, and Cognitive avoidance of the original the Mini-MAC. The Fighting spirit and the Fatalism subscales were combined on the Positive attitude scale. The four factor-derived scale scores exhibited acceptable accuracy for individual measurement purposes, as well as stability over time in test-retest assessments at 6 months. Validity assessments found meaningful relations between the derived scale scores, and Brief Symptom Inventory depression and anxiety scores and Functional Assessment of Chronic Illness Therapy spiritual well-being scores. CONCLUSIONS: The Spanish version of the Mini-MAC provides reliable and valid measures for patients with non-metastatic, resected cancer, and results corroborate the instrument's cross-cultural validity.

ANTECEDENTES/OBJETIVO: El objetivo de este estudio fue analizar las propiedades psicométricas de la versión Española del Mini-Mental Adjustment to Cancer Scale (Mini-MAC) en pacientes con cáncer resecado, no metastásico. MÉTODO: Estudio multicéntrico, prospectivo y observacional con 914 pacientes reclutados en 15 hospitales de España. Se llevaron a cabo análisis factorial exploratorio y confirmatorio, así como análisis de la validez y fiabilidad de las puntuaciones de la escala. RESULTADOS: Los resultados de los análisis factoriales sugieren que la estructura más apropiada para la versión española del Mini-MAC es la de cuatro factores. Tres subescalas derivadas de esta estructura tienen propiedades psicométricas similares a la escala original: Desesperanza, Preocupación ansiosa y Evitación cognitiva. Las subescalas Espíritu de lucha y Fatalismo se combinaron en la escala Actitud positiva. Las puntuaciones en las cuatro escalas mostraron una fiabilidad aceptable para su utilización en la evaluación individual, así como estabilidad a lo largo del tiempo en evaluaciones test-retest a los seis meses. Se obtuvieron evidencias de validez en forma de relaciones significativas con las escalas de ansiedad y depresión del BSI, y de bienestar espiritual del FACIT. CONCLUSIONES: La versión Española del Mini-MAC proporciona puntuaciones fiables y válidas para evaluar las estrategias de afrontamiento en pacientes con cáncer y los resultados añaden evidencia a favor de la validez transcultural del instrumento.

Cognitive Functioning and Cortical Brain Thickness in Acromegaly Patients: A Pilot study.

OBJECTIVE: Cognitive effects in acromegaly patients are poorly understood and the mechanisms involved are still unclear. The aim of this study was to evaluate the cognitive function, depression, and quality of life of acromegaly patients treated with pegvisomant versus somatostatin analogues (SRLs) and to analyze the effect of the different treatments on cognition and possible structural brain changes. METHODS: This cross-sectional study involved 23 acromegaly patients divided into two groups according to treatment modality: One group of 9 patients treated with pegvisomant and another group of 14 patients treated with SRLs. All participants underwent blood analysis, neuropsychological tests, depression tests, quality of life assessment, and 3-Tesla magnetic resonance imaging. RESULTS: We found no significant differences between groups in the neuropsychological tests, depression or quality of life; nor in the whole-brain cortical thickness. In the SRL group, the volume of the thalamus correlated positively with executive function, a correlation not found in the pegvisomant group. In addition, the pegvisomant group had significantly higher levels of insulin than the SRL group. CONCLUSIONS: In conclusion, in this pilot study, the type of pharmacological treatment in patients with acromegaly and good glycemic control did not influence the cognitive function and cortical brain thickness. However, pegvisomant could play a neuroprotective role on the thalamus that will have to be demonstrated with larger samples in future studies.

Psychometric Properties of the PDRQ-9 in Cancer Patients: Patient-Doctor Relationship Questionnaire / Propiedades Psicométricas del PDRQ-9 en Pacientes con Cáncer: Cuestionario de Relación Médico-Paciente

Background: The patient-doctor relationship is an important concept in health care. The aim of this study was to evaluate the psychometric properties, convergent validity, and factorial invariance of the Patient-Doctor Relationship Questionnaire (PDRQ-9). Method: Confirmatory factor analysis was conducted to explore the scale’s dimensionality and test for strong measurement invariance across sex, age, and tumor site in a prospective, multicenter cohort of 560 patients who completed the PDRQ-9, Health-related Quality of Life Questionnaire (EORTC-QLQ-C30), and Brief Symptom Inventory (BSI) scales. Results: The data supported a unidimensional structure. Thresholds and factor loadings could be constrained to be invariant across sex, age, and tumor site, indicating strong measurement invariance. Scores derived from the unidimensional structure exhibited satisfactory degrees of reliability and determinacy. Evidence of convergent validity was supported by modest positive correlations with functional (p<.001) and global quality-of-life (p<.001) and negative correlations with psychological distress (p<.001). Low satisfaction with the oncologist was associated with anxiety (p=.006), and depression (p=.004). Conclusions: The PDRQ-9 is a suitable, valid instrument for assessing the quality of patient-doctor relationships in cancer patients. (AU)

Antecedentes: la relación médico-paciente es un concepto importante en cuidado de la salud. El objetivo de este estudio fue evaluar las propiedades psicométricas, la validez y la invariancia factorial del Cuestionario de Relación Médico-Paciente (PDRQ-9). Método: se realizó un análisis factorial confirmatorio para explorar la dimensionalidad de la escala y la invariancia de medición a través del sexo, la edad y la localización del tumor en una cohorte prospectiva multicéntrico de 560 pacientes que completaron el PDRQ-9, el Cuestionario de Calidad de Vida (EORTC-QLQ-C30) y la Inventario Breve de Síntomas (BSI-18). Resultados: los datos apoyaron una estructura unidimensional. Los umbrales y las cargas de los factores podían considerarse invariantes en función del sexo, la edad y localización de tumor (invariancia fuerte). Las puntuaciones derivadas de la estructura unidimensional mostraron grados satisfactorios de confiabilidad y determinación. La evidencia de validez convergente fue apoyada por correlaciones positivas modestas con la escala funcional (p<.001) y la calidad de vida (p<.001) y correlaciones negativas con malestar psicológico (p<.001). La baja satisfacción con el oncólogo estuvo asociada a mayor ansiedad (p =.006) y depresión (p= .004). Conclusiones: el PDRQ-9 es un instrumento válido y adecuado para evaluar la calidad en la relación médico-paciente en pacientes con cáncer. (AU)

Psychometric properties of Spanish version of the Mini-Mental Adjustment to Cancer Scale / Propiedades psicométricas de la versión Española de la escala Mini-Mental Adjustment to Cancer (Mini-MAC)

Background/Objective: The aim of the study was to examine the factor structure and psychometric properties of the Spanish version of the Mini-Mental Adjustment to Cancer Scale (Mini-MAC) in a large sample of patients with non-metastatic, resected cancer.Methods: Prospective, observational, multicenter study for which 914 patients were recruited from 15 Spanish hospitals. Exploratory and confirmatory factor analyses, validity and reliability analyses were conducted.Results: Factor-analytic results indicated a 4-factor structure of the Spanish version of the Mini-MAC. Three subscales have psychometric properties similar to those of Helplessness, Anxious preoccupation, and Cognitive avoidance of the original the Mini-MAC. The Fighting spirit and the Fatalism subscales were combined on the Positive attitude scale. The four factor-derived scale scores exhibited acceptable accuracy for individual measurement purposes, as well as stability over time in test-retest assessments at 6 months. Validity assessments found meaningful relations between the derived scale scores, and Brief Symptom Inventory depression and anxiety scores and Functional Assessment of Chronic Illness Therapy spiritual well-being scores.Conclusions: The Spanish version of the Mini-MAC provides reliable and valid measures for patients with non-metastatic, resected cancer, and results corroborate the instrument’s cross-cultural validity. (AU)

Antecedentes/Objetivo: El objetivo de este estudio fue analizar las propiedades psicométricas de la versión Española del Mini-Mental Adjustment to Cancer Scale (Mini-MAC) en pacientes con cáncer resecado, no metastásico.Método: Estudio multicéntrico, prospectivo y observacional con 914 pacientes reclutados en 15 hospitales de España. Se llevaron a cabo análisis factorial exploratorio y confirmatorio, así como análisis de la validez y fiabilidad de las puntuaciones de la escala.Resultados: Los resultados de los análisis factoriales sugieren que la estructura más apropiada para la versión española del Mini-MAC es la de cuatro factores. Tres subescalas derivadas de esta estructura tienen propiedades psicométricas similares a la escala original: Desesperanza, Preocupación ansiosa y Evitación cognitiva. Las subescalas Espíritu de lucha y Fatalismo se combinaron en la escala Actitud positiva. Las puntuaciones en las cuatro escalas mostraron una fiabilidad aceptable para su utilización en la evaluación individual, así como estabilidad a lo largo del tiempo en evaluaciones test-retest a los seis meses. Se obtuvieron evidencias de validez en forma de relaciones significativas con las escalas de ansiedad y depresión del BSI, y de bienestar espiritual del FACIT.Conclusiones: La versión Española del Mini-MAC proporciona puntuaciones fiables y válidas para evaluar las estrategias de afrontamiento en pacientes con cáncer y los resultados añaden evidencia a favor de la validez transcultural del instrumento. (AU)

Structural integrity of the contralesional hemisphere predicts cognitive impairment in ischemic stroke at three months.

After stroke, white matter integrity can be affected both locally and distally to the primary lesion location. It has been shown that tract disruption in mirror's regions of the contralateral hemisphere is associated with degree of functional impairment. Fourteen patients suffering right hemispheric focal stroke (S) and eighteen healthy controls (HC) underwent Diffusion Weighted Imaging (DWI) and neuropsychological assessment. The stroke patient group was divided into poor (SP; n = 8) and good (SG; n = 6) cognitive recovery groups according to their cognitive improvement from the acute phase (72 hours after stroke) to the subacute phase (3 months post-stroke). Whole-brain DWI data analysis was performed by computing Diffusion Tensor Imaging (DTI) followed by Tract Based Spatial Statistics (TBSS). Assessment of effects was obtained computing the correlation of the projections on TBSS skeleton of Fractional Anisotropy (FA) and Radial Diffusivity (RD) with cognitive test results. Significant decrease of FA was found only in right brain anatomical areas for the S group when compared to the HC group. Analyzed separately, stroke patients with poor cognitive recovery showed additional significant FA decrease in several left hemisphere regions; whereas SG patients showed significant decrease only in the left genu of corpus callosum when compared to the HC. For the SG group, whole brain analysis revealed significant correlation between the performance in the Semantic Fluency test and the FA in the right hemisphere as well as between the performance in the Grooved Pegboard Test (GPT) and the Trail Making Test-part A and the FA in the left hemisphere. For the SP group, correlation analysis revealed significant correlation between the performance in the GPT and the FA in the right hemisphere.

Thalamic diffusion differences related to cognitive function in white matter lesions.

Cerebral white matter lesions (WMLs) are related to cognitive deficits, probably due to a disruption of frontal-subcortical circuits. We explored thalamic diffusion differences related to white matter lesions (WMLs) and their association with cognitive function in middle-aged individuals. Ninety-six participants from the Barcelona-AsIA Neuropsychology Study were included. Participants were classified into groups based on low grade and high grade of periventricular hyperintensities (PVHs) and deep white matter hyperintensities (DWMHs). Tract-Based Spatial Statistics was used to study thalamic diffusion differences between groups. Mean fractional anisotropy (FA) values in significant areas were calculated for each subject and correlated with cognitive performance. Participants with high-grade PVHs and DWMHs showed lower FA thalamic values compared to those with low-grade PVHs and DWMHs, respectively. Decreased FA thalamic values in high-grade DWMHs, but not high-grade PVH, were related to lower levels of performance in psychomotor speed, verbal fluency, and visuospatial skills. Thalamic diffusion differences are related to lower cognitive function only in participants with high-grade DWMHs. These results support the hypothesis that fronto-subcortical disruption is associated with cognitive function only in DWMHs.

Remote thalamic microstructural abnormalities related to cognitive function in ischemic stroke patients.

OBJECTIVE: Ischemic stroke can lead to a continuum of cognitive sequelae, ranging from mild vascular cognitive impairment to vascular dementia. These cognitive deficits can be influenced by the disruption of cortico-subcortical circuits. We sought to explore remote thalamic microstructural abnormalities and their association with cognitive function after ischemic stroke. METHOD: Seventeen patients with right hemispheric ischemic stroke and 17 controls matched for age, sex, and years of education were included. All participants underwent neurological, neuropsychological, and diffusion tensor image examination. Patients were assessed 3 months poststroke. Voxel-wise analysis was used to study thalamic diffusion differences between groups. Mean fractional anisotropy (FA) and mean diffusivity (MD) values in significant thalamic areas were calculated for each subject and correlated with cognitive performance. RESULTS: Stroke patients showed lower FA values and higher MD values in specific areas of both the left and right thalamus compared with controls. In patients, decreased FA values were associated with lower verbal fluency performance in the right thalamus (R(2) = 0.45, ß = 0.74) and the left thalamus (R(2) = 0.57, ß = 0.77) after adjusting for diabetes mellitus. Moreover, increased MD values were associated with lower verbal fluency performance in the right thalamus (R(2) = 0.27, ß = -0.54) after adjusting for diabetes mellitus. In controls, thalamic FA and MD values were not related to any cognitive function. CONCLUSION: Our findings support the hypothesis that ischemic stroke lesions are associated with remote thalamic diffusion abnormalities, and that these abnormalities can contribute to cognitive dysfunction 3 months after a cerebrovascular event.