Serum neurofilament dynamics predicts neurodegeneration and clinical progression in presymptomatic Alzheimer's disease

Neurofilament light chain (NfL) is a promising fluid biomarker of disease progression for various cerebral proteopathies. Here we leverage the unique characteristics of the Dominantly Inherited Alzheimer Network and ultrasensitive immunoassay technology to demonstrate that NfL levels in the cerebrospinal fluid (n = 187) and serum (n = 405) are correlated with one another and are elevated at the presymptomatic stages of familial Alzheimer's disease. Longitudinal, within-person analysis of serum NfL dynamics (n = 196) confirmed this elevation and further revealed that the rate of change of serum NfL could discriminate mutation carriers from non-mutation carriers almost a decade earlier than cross-sectional absolute NfL levels (that is, 16.2 versus 6.8 years before the estimated symptom onset). Serum NfL rate of change peaked in participants converting from the presymptomatic to the symptomatic stage and was associated with cortical thinning assessed by magnetic resonance imaging, but less so with amyloid-β deposition or glucose metabolism (assessed by positron emission tomography). Serum NfL was predictive for both the rate of cortical thinning and cognitive changes assessed by the Mini-Mental State Examination and Logical Memory test. Thus, NfL dynamics in serum predict disease progression and brain neurodegeneration at the early presymptomatic stages of familial Alzheimer's disease, which supports its potential utility as a clinically useful biomarker

Problem-focused coping underlying lower caregiver burden in ALS-FTD: Implications for caregiver intervention

Objective: Amyotrophic lateral sclerosis (ALS) is a multisystem neurodegenerative disorder which includes cognitive and behavioral symptoms akin to frontotemporal dementia (FTD). Despite the necessity of caregiver intervention to assist with the management of cognitive and behavioral symptoms, there has been a lack of research on the topic. A focus on caregiver coping may offer a promising foundation to guide the development of interventions as part of ALS care. Accordingly, the aim of the present study was to examine the relationships between caregiver coping, psychological morbidity and burden of care in the context of ALS cognitive and behavioral symptoms.  Methods: Fifty-five patient-caregiver dyads were recruited from specialized ALS and FTD clinics. Specific coping strategies were examined using the COPE Inventory/Brief COPE and psychological morbidity and burden were assessed using the Depression, Anxiety, and Stress Scale–21 and Zarit Burden Interview. The relationship between coping, psychological morbidity and burden of care were analyzed using univariate and multivariate methods.  Results: High-burden caregivers were more likely to be caring for patients with a diagnosis of ALS-FTD (p =.0001). Caregivers used problem-focused strategies (particularly planning) more frequently (M = 71.4, SD = 15.3) compared to emotion-focused (M = 60.8, SD = 12.3) and dysfunctional coping strategies (M = 42.2, SD = 8.6). A diagnosis of ALS-FTD (p=.0001) and problem-focused strategies (p=.024) emerged as significant predictors of caregiver burden. Caregiver anxiety, depression and stress were not predictive of caregiver burden (p=.151).  Conclusions: Timely provision of caregiver support optimizing problem-focused coping strategies as part of multidisciplinary ALS care, particularly for caregivers of ALS-FTD patients may mitigate caregiver burden