Willa D. Brenowitz

Body mass index, weight change, and clinical progression in mild cognitive impairment and Alzheimer disease.

The speed and severity of clinical progression after Alzheimer disease (AD) diagnosis varies and depends on multiple factors, most not well elucidated. We assessed whether body mass index (BMI) and 1-year weight change (WC) are associated with clinical progression in amnestic mild cognitive impairment (aMCI) and early-stage AD. Longitudinal data comprising 2268 aMCI and 1506 AD participants in the National Alzheimer’s Coordinating Center’s Uniform Data Set were used to examine nuances of clinical progression by BMI and WC, as well as potential variations in associations by age, sex, BMI (WC model), or apolipoprotein E genotype. In aMCI, high BMI (vs. moderate BMI) was associated with slower progression; weight loss (vs. no WC) was associated with faster progression. In AD, no significant differences were observed in clinical progression by BMI or WC. The association between BMI and clinical progression varied significantly by apolipoprotein E genotype in AD, and the association between WC and clinical progression varied significantly by sex and BMI in aMCI. Baseline BMI and 1-year WC in late life may serve as early prognostic indicators in aMCI and early-stage AD. If replicated, these results may help in counseling patients on anticipated clinical progression and suggest windows of opportunity for intervention.

Arteriolosclerosis that affects multiple brain regions is linked to hippocampal sclerosis of ageing

Hippocampal sclerosis of ageing is a prevalent brain disease that afflicts older persons and has been linked with cerebrovascular pathology. Arteriolosclerosis is a subtype of cerebrovascular pathology characterized by concentrically thickened arterioles. Here we report data from multiple large autopsy series (University of Kentucky Alzheimers Disease Centre, Nun Study, and National Alzheimers Coordinating Centre) showing a specific association between hippocampal sclerosis of ageing pathology and arteriolosclerosis. The present analyses incorporate 226 cases of autopsy-proven hippocampal sclerosis of ageing and 1792 controls. Case-control comparisons were performed including digital pathological assessments for detailed analyses of blood vessel morphology. We found no evidence of associations between hippocampal sclerosis of ageing pathology and lacunar infarcts, large infarcts, Circle of Willis atherosclerosis, or cerebral amyloid angiopathy. Individuals with hippocampal sclerosis of ageing pathology did not show increased rates of clinically documented hypertension, diabetes, or other cardiac risk factors. The correlation between arteriolosclerosis and hippocampal sclerosis of ageing pathology was strong in multiple brain regions outside of the hippocampus. For example, the presence of arteriolosclerosis in the frontal cortex (Brodmann area 9) was strongly associated with hippocampal sclerosis of ageing pathology (P < 0.001). This enables informative evaluation of anatomical regions outside of the hippocampus. To assess the morphology of brain microvasculature far more rigorously than what is possible using semi-quantitative pathological scoring, we applied digital pathological (Aperio ScanScope) methods on a subsample of frontal cortex sections from hippocampal sclerosis of ageing (n = 15) and control (n = 42) cases. Following technical studies to optimize immunostaining methods for small blood vessel visualization, our analyses focused on sections immunostained for smooth muscle actin (a marker of arterioles) and CD34 (an endothelial marker), with separate analyses on grey and white matter. A total of 43 834 smooth muscle actin-positive vascular profiles and 603 798 CD34-positive vascular profiles were evaluated. In frontal cortex of cases with hippocampal sclerosis of ageing, smooth muscle actin-immunoreactive arterioles had thicker walls (P < 0.05), larger perimeters (P < 0.03), and larger vessel areas (P < 0.03) than controls. Unlike the arterioles, CD34-immunoreactive capillaries had dimensions that were unchanged in cases with hippocampal sclerosis of ageing versus controls. Arteriolosclerosis appears specific to hippocampal sclerosis of ageing brains, because brains with Alzheimers disease pathology did not show the same morphological alterations. We conclude that there may be a pathogenetic change in aged human brain arterioles that impacts multiple brain areas and contributes to hippocampal sclerosis of ageing.

Cerebral amyloid angiopathy and its co-occurrence with Alzheimer's disease and other cerebrovascular neuropathologic changes

We examined the relationship between cerebral amyloid angiopathy (CAA), Alzheimers disease neuropathologic changes, other vascular brain pathologies, and cognition in a large multicenter autopsy sample. Data were obtained from the National Alzheimers Coordinating Center on autopsied subjects (N = 3976) who died between 2002 and 2012. Descriptive statistics and multivariable regression models estimated the associations between CAA and other pathologies, and between CAA severity and cognitive test scores proximal to death. CAA tended to co-occur with Alzheimers disease neuropathologic changes but a minority of cases were discrepant. CAA was absent in 22% (n = 520) of subjects with frequent neuritic plaques but present in 20.9% (n = 91) of subjects with no neuritic plaques. In subjects with no/sparse neuritic plaques, nonhemorrhagic brain infarcts were more common in those with CAA pathology than without (p = 0.007). In subjects without the APOE ε4 allele, CAA severity was associated with lower cognition proximal to death, factoring in other pathologies. The presence of CAA in patients without Alzheimers disease may indicate a distinct cerebrovascular condition.

Longitudinal Associations between Self-Rated Health and Performance-Based Physical Function in a Population-Based Cohort of Older Adults

Background Although self-rated health (SRH) and performance-based physical function (PPF) are both strong predictors of mortality, little research has investigated the relationships between them. The objective of this study was to evaluate longitudinal, bi-directional associations between SRH and PPF. Methods We evaluated longitudinal associations between SRH and PPF in 3,610 adults aged 65–89 followed for an average of 4.8 (standard deviation [SD]: 4.4) years between 1994 and July 2011 in the Adult Changes in Thought study, a population-based cohort in the Seattle area. SRH was assessed with a single-item question in the ACT study. Participants were asked at each evaluation to rate their health as “excellent”, “very good”, “good”, “fair”, or “poor” in response to the question “In general, how would you rate your health at this time”. PPF scores (ranging from 0–16, with higher indicating better performance) included walking speed, chair rises, grip strength, and balance. Results At the baseline visit, participants averaged 74.5 (SD: 5.8) years of age and 2,115 (58.6%) were female. In multivariable linear mixed models, PPF declined with age, with more rapid decreases associated with very good, good, and fair (vs. excellent) baseline SRH. Adjusted annual change in PPF was −0.17 points (95% confidence interval [CI]: −0.19, −0.15) for individuals with excellent baseline SRH and −0.21 points (95% CI: −0.22, −0.19) for participants with fair SRH. In multivariable generalized linear mixed models, lower baseline PPF quartiles were associated with lower odds of excellent/very good/good SRH at age 75, however, differences between baseline PPF quartiles diminished with age. Conclusions These results suggest that less than excellent SRH predicts decline in physical functioning, however, poor physical functioning may not predict change in SRH in a reciprocal fashion. SRH provides a simple assessment tool for identifying individuals at increased risk for decline in physical function.

Mixed neuropathologies and estimated rates of clinical progression in a large autopsy sample

Whether co‐occurring neuropathologies interact or independently affect clinical disease progression is uncertain. We estimated rates of clinical progression and tested whether associations between clinical progression and Alzheimers disease neuropathology (ADNP) were modified by co‐occurring Lewy body disease (LBD) or vascular brain injury (VBI).

Social relationships and risk of incident mild cognitive impairment in US alzheimer's disease centers

Social relationships are hypothesized to prevent or slow cognitive decline. We sought to evaluate associations between social relationships and mild cognitive impairment (MCI). Participants from the National Alzheimer’s Coordinating Center database who were cognitively normal, aged 55 and older at baseline, and had at least 2 in-person visits (n=5335) were included. Multivariable Cox proportional hazard models evaluated the association between 4 social relationships at baseline (marital status, living situation, having children, and having siblings) and risk of developing MCI (on the basis of clinician diagnosis following established criteria). Primary models were adjusted for baseline demographics. Participants were followed, on average, for 3.2 years; 15.2% were diagnosed with MCI. Compared with married participants, risk of MCI was significantly lower for widowed participants (hazard ratio: 0.87; 95% confidence interval: 0.76, 0.99) but not for divorced/separated or never-married participants. Compared with living with a spouse/partner, risk of MCI was significantly higher for living with others (hazard ratio: 1.35; 95% confidence interval: 1.03, 1.77) but not for living alone. Risk of MCI was not associated with having children or having siblings. These results did not consistently identify social relationships as a strong risk factor for, or independent clinical predictor of, MCI.

Mixed neuropathologies and associations with domain-specific cognitive decline

Objective: To test whether decline in specific cognitive domains associated with Alzheimer disease neuropathologic change (ADNC) is modified by co-occurrence of other neuropathologies such as Lewy body disease (LBD) or vascular brain injury (VBI). Methods: Data came from 1,603 autopsied participants evaluated at US Alzheimers Disease Centers. Standardized z scores in memory, attention, language, and executive function were derived from neuropsychological test scores assessed at each annual visit. Multivariable linear mixed-effects models assessed associations between neuropathologies and longitudinal trajectories of domain scores. Results: Compared to other participants, those with ADNC + LBD generally had worse cognitive trajectories, particularly lower initial executive function and faster attention decline. Participants with ADNC + VBI typically had less impairment and slower decline. Interactions were significant between LBD and ADNC for memory (p = 0.046) and between VBI and ADNC for language (p = 0.03); decline was slower than expected if these neuropathologies acted additively on the rate of decline. In secondary models, these interactions were limited to those with high ADNC (but not intermediate ADNC). In a subset of 260 participants with data on microinfarct location, cortical and subcortical microinfarcts were associated with decline in memory, language, and executive function in those without ADNC, but this effect was reduced among those with ADNC. Conclusions: ADNC + LBD (but not ADNC + VBI) was associated with poorer executive function and attention compared to other pathology groupings. However, the effect of co-occurring pathologies on cognitive trajectories may depend on the severity of ADNC. Future studies using antemortem biomarkers should seek to replicate these neuropathologic observations.

Treated hypothyroidism is associated with cerebrovascular disease but not Alzheimer's disease pathology in older adults

Thyroid hormone disease is common among older adults and is associated with cognitive impairment. However, pathologic correlates are not well understood. We studied pathologic and clinical factors associated with hypothyroidism, the most common manifestation of thyroid disease, in research subjects seen annually for clinical evaluations at U.S. Alzheimers Disease Centers. Thyroid disease and treatment status were assessed during clinician interviews. Among autopsied subjects, there were 555 participants with treated hypothyroidism and 2146 without known thyroid disease; hypothyroidism was associated with severe atherosclerosis (odds ratio: 1.35; 95% confidence interval: 1.02, 1.79) but not Alzheimers disease pathologies (amyloid plaques or neurofibrillary tangles). Among participants who did not undergo autopsy (4598 with treated hypothyroidism and 20,945 without known thyroid hormone disease), hypercholesterolemia and cerebrovascular disease (stroke and/or transient ischemic attack) were associated with hypothyroidism, complementing findings in the smaller autopsy sample. This is the first large-scale evaluation of neuropathologic concomitants of hypothyroidism in aged individuals. Clinical hypothyroidism was prevalent (>20% of individuals studied) and was associated with cerebrovascular disease but not Alzheimers disease-type neuropathology.

EVALUATING REVERSE CAUSATION BETWEEN DEMENTIA AND HEARING IMPAIRMENT USING A GENETIC RISK SCORE FOR ALZHEIMER’S DISEASE

antipsychotic in the past year. Cholinesterase inhibitors, memantine, and combination therapies contributed to 87%, 13%, and <1% of prescription initiations, respectively. No differences were seen in choice of initial treatment strategy by sex. Initiation with memantine was higher among patients with vascular dementia and older age at diagnosis, and calendar time (Figure 1). Median time from diagnosis to treatment initiation was 0.3 years (interquartile range 0.1, 0.8) and was similar among the 3 cholinesterase inhibitors and memantine, but was longer for combination therapy. Conclusions:This study was the first to evaluateMND treatment patterns by sex and MND subtype and to our knowledge, is the largest MND drug utilization study to date.With a total follow-up period of up to 20 years that covers the entire period that these MND drugs have been available, this study characterized their use in a realworld setting.

ASSOCIATION BETWEEN ANTIDEPRESSANT USE AND INCIDENT MCI IN OLDER ADULTS WITH DEPRESSION

Beta(13w30Hz), Gamma(30w50Hz). Absolute power is the sum of each EEG power wave. Relative power was calculated as the absolute power of eachwave divided by the sumof absolute power of all waves. Relative power without delta was calculated as the absolute power of each wave divided by the sum of absolute power of the rest waves excepting for delta. Results:Alpha wave showed the striking results among all waves. Alpha absolute power in AD decreased compared to control group. (Figure 1.A)The relative power and the relative power without delta waves in AD decreased compared to the control group (Figure 1.B, C), which has shown similiar to other studies. The alpha power’s gap between AD patients and controls showed the clear distinction in the relative powerwithout delta. Themost effective result was obtained from relative power without delta. Conclusions:Variance of delta had most influence on the result. Even though obtaining EEG was difficult due to delta signal, we showed the possibility that dementia could be diagnosed by measuring EEG signals, especially using relative power of brain waves without delta. This study was supported by 2016 Fund of Chungnam National University.