Alzheimer's disease disrupts alpha and beta-band resting-state oscillatory network connectivity

Objective: Neuroimaging studies in Alzheimer’s disease (AD) yield conflicting results due to selective investigation. We conducted a comprehensive magnetoencephalography study of connectivity changes in AD and healthy ageing in the resting-state. Methods: We performed a whole-brain, source-space assessment of oscillatory neural signalling in multiple frequencies comparing AD patients, elderly and young controls. We compared eyes-open and closed group oscillatory envelope activity in networks obtained through temporal independent component analysis, and calculated whole-brain node-based amplitude and phase connectivity. Results: In bilateral parietotemporal areas, oscillatory envelope amplitude increased with healthy ageing, whereas both local amplitude and node-to-global connectivity decreased with AD. AD-related decreases were spatially specific and restricted to the alpha and beta bands. A significant proportion of the variance in areas of peak group difference was explained by cognitive integrity, in addition to group. None of the groups differed in phase connectivity. Results were highly similar for eyes-open and closed resting-state. Conclusions: These results support the disconnection syndrome hypothesis and suggest that AD shows distinct and unique patterns of disrupted neural functioning, rather than accelerated healthy ageing. Significance: Whole-brain assessments show that disrupted regional oscillatory envelope amplitude and connectivity in the alpha and beta bands play a key role in AD

Measurement of Treatment Burden in Patients with Multimorbidity in the Netherlands:translation and Validation of the Multimorbidity Treatment Burden Questionnaire (NL-MTBQ)

Background. Multimorbidity is a growing problem. The number and complexity of (non-)pharmaceutical treatments creates a great burden for patients. Treatment burden refers to the perception of the weight of these treatments, and is associated with multimorbidity. Measurement of treatment burden is of great value for optimizing treatment and health-related outcomes. Objective. We aim to translate and validate the Multimorbidity Treatment Burden Questionnaire (MTBQ) for use in the Dutch population with multimorbidity and explore the level of treatment burden. Methods. Translating the MTBQ into Dutch included forward-backward translation, piloting and cognitive interviewing (n=8). Psychometric properties of the questionnaire were assessed in a cross-sectional study of patients with multimorbidity recruited from a panel in the Netherlands (n=959). We examined item properties, dimensionality, internal consistency reliability and construct validity. The level of treatment burden in the population was assessed. Results. The mean age among 959 participants with multimorbidity was 69.9 (17–96) years. Median global NL-MTBQ score was 3.85 (IQR 0-9.62), representing low treatment burden. Significant floor effects were found for all 13 items of the instrument. Factor analysis supported a single-factor structure. The NL-MTBQ had high internal consistency (α=0.845), and provided good evidence on the construct validity of the scale.Conclusion. The Dutch version of the 13-item MTBQ is a single-structured, valid and compact patient-reported outcome measure to assess treatment burden in primary care patients with multimorbidity. It could identify patients experiencing high treatment burden, with great potential to enhance shared-decision making and offer additional support.<br/