Wennberg, Alexandra

Sleep quality and its association with cognition has been widely studied in some neurodegenerative diseases, but less is known about this association in spinal muscular atrophy (SMA). In adult SMA ( n = 21) patients and age-matched controls ( n = 23), we assessed subjectively measured sleep quality and daytime somnolence. Cognition was assessed with a multi-domain neuropsychological battery. Further, we investigated the association between clinical functional scores and sleep questionnaire scores. Among SMA patients, better motor and limb function was associated with better subjective sleep quality ( p’s< 0.05). Clinicians should consider sleep quality in patient care and future studies are needed to better understand these relationships.

Background: Transactive response DNA-binding protein of 43 kDa (TDP-43) is associated with hippocampal atrophy in Alzheimer’s disease (AD), but whether the association is modified by other factors is unknown. Objective: To evaluate whether the associations between TDP-43 and hippocampal volume and atrophy rate are affected by age, gender, apolipoprotein E ( APOE) ɛ4, Lewy bodies (LBs), amyloid-β (Aβ), or Braak neurofibrillary tangle (NFT) stage. Methods: In this longitudinal neuroimaging-clinicopathological study of 468 cases with AD neuropathological changes (Aβ-positive) that had completed antemortem head MRI, we investigated how age, gender, APOE ɛ4, presence of LBs, Aβ, TDP-43, and Braak NFT stages are associated with hippocampal volumes and rates of atrophy over time. We included field strength in the models since our cohort included 1.5T and 3T scans. We then determined whether the associations between hippocampal atrophy and TDP-43 are modified by these factors using mixed effects models. Results: Older age, female gender, APOE ɛ4, higher field strength, higher TDP-43, and Braak NFT stages were associated with smaller hippocampi. Rate of atrophy was greater with higher TDP-43 and Braak NFT stage, but lower in older patients. The association of TDP-43 with greater rate of atrophy was enhanced in APOE ɛ4 carriers ( p = 0.04). Conclusion: Neurodegenerative effects of TDP-43 seem to be independent of most factors except perhaps APOE in cases with AD neuropathological changes. TDP-43 and tau appear to behave independently of one another.

Introduction The reasons why women are at higher risk than men for developing dementia are unclear. Although studies implicate sex differences in the effect of stress on cognitive functioning, whether stressful life events are associated with subsequent cognitive decline has received scant research attention. Methods In Wave 3 (1993–1996) of the Baltimore Epidemiologic Catchment Area study, 337 men and 572 women (mean age = 47 years) reported recent (within the last year) and remote (from 1981 until 1 year ago) traumatic events (eg, combat) and stressful life events (eg, divorce/separation). At Waves 3 and 4 (2004–2005), they completed the Mini Mental State Examination (MMSE) and a word‐list memory test. Multivariable models were used to examine the association between traumatic and stressful life events at Wave 3 and cognitive change by Wave 4. Results A greater number of recent stressful life events at Wave 3, but not of more remote stressful events, was associated with greater verbal memory decline by Wave 4 in women but not in men. Stressful events were not associated with change in MMSE, and there were no associations between traumatic events occurring at any time and subsequent memory or MMSE decline in either sex. Conclusions Unlike men, middle‐aged women with a greater number of recent stressful life events demonstrate memory decline over a decade later. Sex differences in cognitive vulnerability to stressful life events may underlie women's increased risk of memory impairment in late life, suggesting that stress reduction interventions may help prevent cognitive decline in women.

ObjectivesTo determine the association of napping intention, frequency, and duration with cognition in a nationally‐representative sample of US older adults.MethodsWe performed a cross‐sectional analysis of community‐dwelling Medicare beneficiaries aged ≥65 years from Rounds 3 or 4 (2013‐2014) of the National Health and Aging Trends Study (N = 2549). Participants reported past‐month napping intention (intentional/unintentional), napping frequency (rarely/never [non‐nappers], some days [infrequent nappers], most days/every day [frequent nappers]), and average nap duration (we categorized as ≤30 minutes [short]; 31‐60 minutes [moderate]; and > 60 minutes [long]). Cognitive outcomes were performance on immediate and delayed word recall tests (IWR and DWR, respectively), the Clock Drawing Test (CDT), and self‐rated memory (score: 1[excellent]‐5[very poor]).ResultsAfter adjustment for potential confounders, unintentional nappers had poorer immediate word recall test performance than non‐nappers (B = −0.23, P < 0.01) and intentional nappers (B = −0.26, P < 0.01). After further adjustment for daytime sleepiness, frequent nappers reported poorer self‐rated memory than non‐nappers (B = 0.14, P < 0.05). Compared with short nappers, long nappers had poorer IWR (B = −0.26, P < 0.05) and CDT scores (B = −0.17, P < 0.05). Except for the association of nap duration with IWR and CDT, these associations remained after excluding participants with dementia and/or proxy respondents. Among participants undiagnosed with dementia or proxies, moderate‐duration naps were associated with better DWR than short naps (B = 0.24, P < 0.05). Neither napping intentionality nor frequency was associated with CDT performance.ConclusionsAmong older adults, distinct aspects of napping are associated with cognitive performance. Prospective research, with objective measures of napping, is needed to elucidate the link between napping and cognitive trajectories.

Abstract Background Chronic inflammation has been linked with geriatric-related conditions, including dementia. Inflammatory cytokine levels, including interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF) α, in the blood have been associated with cognitive impairment and decline. However, evidence has been mixed. Methods We examined the cross-sectional and longitudinal associations between baseline-measured IL-6, IL-10, and TNFα levels and the ratio of IL-6/IL-10 with cognitive test performance and mild cognitive impairment (MCI) among 1,602 community-dwelling older adults (median age = 72.8) enrolled in the Mayo Clinic Study of Aging. Approximately half (46.5%) of participants were female and 98.6% were white. At baseline and follow-up visits (occurring at 15-month intervals), participants completed neuropsychological testing, blood draws, and had a clinical consensus diagnosis. Results In multivariable cross-sectional analyses, we did not observe an association between inflammatory cytokine levels and global or domain-specific cognitive z scores; however, higher IL-6 and IL-10 levels were associated with greater odds of a MCI diagnosis. Longitudinally, we did not observe any association between inflammatory cytokine levels and cognitive test performance or risk of MCI. Sex, age, cognitive status, APOE ε4 genotype, diabetes, depression, and cerebral amyloid-beta deposition were not effect modifiers. Conclusions These results suggest that plasma inflammatory markers may not be useful to ascertain risk for cognitive decline and MCI in the general population.