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Primary age-related tauopathy is increasingly recognized as a separate neuropathological entity different from Alzheimer's disease. Both share the neuropathological features of tau aggregates and neuronal loss in the temporal lobe, but primary age-related tauopathy lacks the requisite amyloid plaques central to Alzheimer's disease. While both have similar clinical presentations, individuals with symptomatic primary age-related tauopathy are commonly of more advanced ages with milder cognitive dysfunction. Direct comparison of the neuropsychological trajectories of primary age-related tauopathy and Alzheimer's disease has not been thoroughly evaluated and thus, our objective was to determine how cognitive decline differs longitudinally between these two conditions after the onset of clinical symptoms. Data were obtained from the National Alzheimer's Coordinating Center on participants with mild cognitive impairment at baseline and either no neuritic plaques (i.e. primary age-related tauopathy) or moderate to frequent neuritic plaques (i.e. Alzheimer neuropathological change) at subsequent autopsy. For patients with Alzheimer's disease and primary age-related tauopathy, we compared rates of decline in the sum of boxes score from the CDR® Dementia Staging Instrument and in five cognitive domains (episodic memory, attention/working memory, executive function, language/semantic memory, and global composite) using z-scores for neuropsychological tests that were calculated based on scores for participants with normal cognition. The differences in rates of change were tested using linear mixed-effects models accounting for clinical centre clustering and repeated measures by individual. Models were adjusted for sex, age, education, baseline test score, Braak stage, apolipoprotein ε4 (APOE ε4) carrier status, family history of cognitive impairment, and history of stroke, hypertension, or diabetes. We identified 578 participants with a global CDR of 0.5 (i.e. mild cognitive impairment) at baseline, 126 with primary age-related tauopathy and 452 with Alzheimer's disease. Examining the difference in rates of change in CDR sum of boxes and in all domain scores, participants with Alzheimer's disease had a significantly steeper decline after becoming clinically symptomatic than those with primary age-related tauopathy. This remained true after adjusting for covariates. The results of this analysis corroborate previous studies showing that primary age-related tauopathy has slower cognitive decline than Alzheimer's disease across multiple neuropsychological domains, thus adding to the understanding of the neuropsychological burden in primary age-related tauopathy. The study provides further evidence to support the hypothesis that primary age-related tauopathy has distinct neuropathological and clinical features compared to Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Background: Identifying individuals at risk for developing Alzheimer disease (AD) is of utmost importance. Although genetic studies have identified AD-associated SNPs in APOE and other genes, genetic information has not been integrated into an epidemiological framework for risk prediction.Methods and Findings: Using genotype data from 17,008 AD cases and 37,154 controls from the International Genomics of Alzheimer's Project (IGAP Stage 1), we identified AD-associated SNPs (at p < 10-5). We then integrated these AD-associated SNPs into a Cox proportional hazard model using genotype data from a subset of 6,409 AD patients and 9,386 older controls from Phase 1 of the Alzheimer's Disease Genetics Consortium (ADGC), providing a polygenic hazard score (PHS) for each participant. By combining population-based incidence rates and the genotype-derived PHS for each individual, we derived estimates of instantaneous risk for developing AD, based on genotype and age, and tested replication in multiple independent cohorts (ADGC Phase 2, National Institute on Aging Alzheimer's Disease Center [NIA ADC], and Alzheimer's Disease Neuroimaging Initiative [ADNI], total n = 20,680). Within the ADGC Phase 1 cohort, individuals in the highest PHS quartile developed AD at a considerably lower age and had the highest yearly AD incidence rate. Among APOE ε3/3 individuals, the PHS modified expected age of AD onset by more than 10 y between the lowest and highest deciles (hazard ratio 3.34, 95% CI 2.62-4.24, p = 1.0 × 10-22). In independent cohorts, the PHS strongly predicted empirical age of AD onset (ADGC Phase 2, r = 0.90, p = 1.1 × 10-26) and longitudinal progression from normal aging to AD (NIA ADC, Cochran-Armitage trend test, p = 1.5 × 10-10), and was associated with neuropathology (NIA ADC, Braak stage of neurofibrillary tangles, p = 3.9 × 10-6, and Consortium to Establish a Registry for Alzheimer's Disease score for neuritic plaques, p = 6.8 × 10-6) and in vivo markers of AD neurodegeneration (ADNI, volume loss within the entorhinal cortex, p = 6.3 × 10-6, and hippocampus, p = 7.9 × 10-5). Additional prospective validation of these results in non-US, non-white, and prospective community-based cohorts is necessary before clinical use.Conclusions: We have developed a PHS for quantifying individual differences in age-specific genetic risk for AD. Within the cohorts studied here, polygenic architecture plays an important role in modifying AD risk beyond APOE. With thorough validation, quantification of inherited genetic variation may prove useful for stratifying AD risk and as an enrichment strategy in therapeutic trials. [ABSTRACT FROM AUTHOR]

Background: Children with hydrocephalus are at risk for epilepsy both due to their underlying condition and as a consequence of surgical treatment; however, the relative contributions of these factors remain unknown.Objective: The authors sought to characterize epilepsy among children with infancy-onset hydrocephalus and to examine the risks of epilepsy associated with hydrocephalus subtype and with factors related to surgical treatment.Methods: We conducted a longitudinal cohort study of all children with infancy-onset hydrocephalus treated at a major regional children's hospital during 2002 to 2012, with follow-up to ascertain risk factors and epilepsy outcome through April 2015. Poisson regression was used to calculate adjusted risk ratios and 95% confidence intervals for associations.Results: Among 379 children with hydrocephalus, 86 (23%) developed epilepsy (mean onset age = 2.7 years), almost one fifth of whom had a history of infantile spasms. Relative to spina bifida-associated hydrocephalus, children with other major hydrocephalus subtypes had fourfold higher risks of developing epilepsy. Among children who underwent surgery, surgical infection doubled the risk of epilepsy (risk ratio = 2.0, 95% confidence interval = 1.4 to 3.0). Epilepsy was associated with surgical failure for intracranial reasons but not extracranial reasons (risk ratio = 1.7, 95% confidence interval = 1.1 to 2.7; risk ratio = 1.1, 95% confidence interval = 0.7 to 1.9, respectively).Conclusions: Epilepsy is common among children with hydrocephalus. Compared with children with spina bifida-associated hydrocephalus, children with other major hydrocephalus subtypes have a markedly increased risk of epilepsy. Surgical infection doubles the risk of epilepsy. [ABSTRACT FROM AUTHOR]

Hippocampal sclerosis of aging (HS-Aging) neuropathology was observed in more than 15% of aged individuals in prior studies. However, much remains unknown about the clinical correlates of HS-Aging pathology or the association(s) between HS-Aging, Alzheimer's disease (AD), and frontotemporal lobar degeneration (FTLD) pathology. Clinical and comorbid pathological features linked to HS-Aging pathology were analyzed using National Alzheimer's Coordinating Center (NACC) data. From autopsy data extending back to 1990 (n = 9,817 participants), the neuropathological diagnoses were evaluated from American AD Centers (ADCs). Among participants who died between 2005-2012 (n = 1,422), additional analyses identified clinical and pathological features associated with HS-Aging pathology. We also compared cognitive testing and longevity outcomes between HS-Aging cases and a subsample with non-tauopathy FTLD (n = 210). Reporting of HS-Aging pathology increased dramatically among ADCs in recent years, to nearly 20% of autopsies in 2012. Participants with relatively "pure" HS-Aging pathology were often diagnosed clinically as having probable (68%) or possible (15%) AD. However, the co-occurrence of HS-Aging pathology and AD neuropathology (AD-NP) did not indicate any pattern of correlation between the two pathologies. Compared with other pathologies, participants with HS-Aging pathology had higher overall cognitive/functional ability (versus AD-NP) and verbal fluency (versus both AD-NP and FTLD) but similar episodic memory impairment at one clinic visit 2-5 years prior to death. Patients with HS-Aging live considerably longer than patients with non-tauopathy FTLD. We conclude that the manifestations of HS-Aging, increasingly recognized in recent years, probably indicate a separate disease process of direct relevance to patient care, dementia research, and clinical trials. [ABSTRACT FROM AUTHOR]

Background/Aims: Evidence suggests that patients with dementia with Lewy bodies (DLB) may have more nocturnal sleep disturbance than patients with Alzheimer's disease (AD). We sought to confirm such observations using a large, prospectively collected, standardized, multicenter-derived database, i.e. the National Alzheimer's Coordinating Center Uniform Data Set. Methods: Nocturnal sleep disturbance (NSD) data, as characterized by the Neuropsychiatric Inventory Questionnaire (NPI-Q), were derived from 4,531 patients collected between September 2005 and November 2008 from 32 National Institute on Aging participating AD centers. Patient and informant characteristics were compared between those with and without NSD by dementia diagnosis (DLB and probable AD). Finally, a logistic regression model was created to quantify the association between NSD status and diagnosis while adjusting for these patient/informant characteristics, as well as center. Results: NSD was more frequent in clinically diagnosed DLB relative to clinically diagnosed AD (odds ratio = 2.93, 95% confidence interval = 2.22-3.86). These results were independent from the gender of the patient or informant, whether the informant lived with the patient, and other patient characteristics, such as dementia severity, depressive symptoms, and NPI-Q-derived measures of hallucinations, delusions, agitation and apathy. In AD, but not DLB, patients, NSD was associated with more advanced disease. Comorbidity of NSD with hallucinations, agitation and apathy was higher in DLB than in AD. There was also evidence that the percentage of DLB cases with NSD showed wide variation across centers. Conclusion: As defined by the NPI-Q, endorsement of the nocturnal behavior item by informants is more likely in patients with DLB when compared to AD, even after the adjustment of key patient/informant characteristics. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objective: Two groups of elderly subjects were studied to see whether patterns of visits to physicians changed after one group received the diagnosis of Alzheimer's disease.Design: Case-control study.Setting: Health maintenance organization (HMO).Patients/participants: Two groups of ambulatory subjects (mean age 77 years) were enrolled from an HMO population for this case-control study: 120 cases had probable Alzheimer's disease diagnosed at enrollment, and another 120 cognitively intact controls with similar comorbidity were enrolled after being frequency-matched for age and gender. Exclusion criteria were nursing home admission and death during the study period.Interventions: None.Measurements and Main Results: Medical records were examined for a four-year period: two years prior to and two years following enrollment and diagnosis. Physician visits declined slightly after enrollment for the persons receiving the diagnosis of Alzheimer's disease [17.5/2 years prior vs 16.5/2 years after (NS)], whereas visits increased over time for the controls [13.7/2 vs 16.3/2 (p < 0.05)], hence the rates were similar after enrollment [16.5 vs 16.3 (NS)]. The proportion of subjects with fewer visits during the period after enrollment was higher among the cases than it was among the controls [54% vs 37%; odds ratio = 2.0 (95% confidence interval = 1.6, 3.1)]. Hospitalizations and emergency department use did not change significantly after enrollment.Conclusions: Physician visit frequency was high before, then decreased after, demented patients received their diagnosis, approaching the frequency in a control population without dementia. This phenomenon cannot be accounted for by nursing home placement, comorbidity, or mortality. Increased hospitalization and emergency department use did not ensue after diagnosis. [ABSTRACT FROM AUTHOR]

Context: Some evidence suggests that treating vascular risk factors and performing mentally stimulating activities may delay cognitive impairment onset in older adults. Exposure to a complex neighborhood environment may be one mechanism to help delay cognitive decline.Evidence Acquisition: PubMed, Web of Science, and ProQuest Dissertation and Theses Global database were systematically reviewed, identifying 25 studies published from February 1, 1989 to March 5, 2016 (data synthesized, May 3, 2015 to October 7, 2016). The review was restricted to quantitative studies focused on: (1) neighborhood social and built environment and cognition; and (2) community-dwelling adults aged ≥45 years.Evidence Synthesis: The majority of studies were cross-sectional, U.S.-based, and found at least one significant association. The diversity of measures and neighborhood definitions limited the synthesis of findings in many instances. Evidence was moderately strong for an association between neighborhood SES and cognition, and modest for associations between neighborhood demographics, design, and destination accessibility and cognition. Most studies examining effect modification found significant associations, with some evidence for effect modification of the neighborhood SES-cognition association by individual-level SES. No studies had low risk of bias and many tested multiple associations that increased the chance of a statistically significant finding. Considering the studies to date, the evidence for an association between neighborhood characteristics and cognition is modest.Conclusions: Future studies should include longitudinal measures of neighborhood characteristics and cognition; examine potential effect modifiers, such as sex and disability; and study mediators that may help elucidate the biological mechanisms linking neighborhood environment and cognition. [ABSTRACT FROM AUTHOR]

Background: Great heterogeneity exists in survival and the interval between onset of motor symptoms and dementia symptoms across synucleinopathies. We aimed to identify genetic and pathological markers that have the strongest association with these features of clinical heterogeneity in synucleinopathies.Methods: In this retrospective study, we examined symptom onset, and genetic and neuropathological data from a cohort of patients with Lewy body disorders with autopsy-confirmed α synucleinopathy (as of Oct 1, 2015) who were previously included in other studies from five academic institutions in five cities in the USA. We used histopathology techniques and markers to assess the burden of tau neurofibrillary tangles, neuritic plaques, α-synuclein inclusions, and other pathological changes in cortical regions. These samples were graded on an ordinal scale and genotyped for variants associated with synucleinopathies. We assessed the interval from onset of motor symptoms to onset of dementia, and overall survival in groups with varying levels of comorbid Alzheimer's disease pathology according to US National Institute on Aging-Alzheimer's Association neuropathological criteria, and used multivariate regression to control for age at death and sex.Findings: On the basis of data from 213 patients who had been followed up to autopsy and met inclusion criteria of Lewy body disorder with autopsy-confirmed α synucleinopathy, we identified 49 (23%) patients with no Alzheimer's disease neuropathology, 56 (26%) with low-level Alzheimer's disease neuropathology, 45 (21%) with intermediate-level Alzheimer's disease neuropathology, and 63 (30%) with high-level Alzheimer's disease neuropathology. As levels of Alzheimer's disease neuropathology increased, cerebral α-synuclein scores were higher, and the interval between onset of motor and dementia symptoms and disease duration was shorter (p<0·0001 for all comparisons). Multivariate regression showed independent negative associations of cerebral tau neurofibrillary tangles score with the interval between onset of motor and dementia symptoms (β -4·0, 95% CI -5·5 to -2·6; p<0·0001; R2 0·22, p<0·0001) and with survival (-2·0, -3·2 to -0·8; 0·003; 0·15, <0·0001) in models that included age at death, sex, cerebral neuritic plaque scores, cerebral α-synuclein scores, presence of cerebrovascular disease, MAPT haplotype, and APOE genotype as covariates.Interpretation: Alzheimer's disease neuropathology is common in synucleinopathies and confers a worse prognosis for each increasing level of neuropathological change. Cerebral neurofibrillary tangles burden, in addition to α-synuclein pathology and amyloid plaque pathology, are the strongest pathological predictors of a shorter interval between onset of motor and dementia symptoms and survival. Diagnostic criteria based on reliable biomarkers for Alzheimer's disease neuropathology in synucleinopathies should help to identify the most appropriate patients for clinical trials of emerging therapies targeting tau, amyloid-β or α synuclein, and to stratify them by level of Alzheimer's disease neuropathology.Funding: US National Institutes of Health (National Institute on Aging and National Institute of Neurological Disorders and Stroke). [ABSTRACT FROM AUTHOR]

We investigated the risk of Parkinson's disease (PD) associated with calcium channel blockers (CCBs) and beta-blockers in a population-based case-control study of 206 men and women between ages 35 and 89 with a new diagnosis of idiopathic PD between 1992 and 2002, and 383 controls without PD or other neurodegenerative disorders who were frequency matched on age, sex, duration of GHC enrollment and clinic. The adjusted odds ratio associated with ever use was 0.85 (95% confidence interval [CI]: 0.43, 1.66) for CCBs, and 1.20 (95% CI: 0.71, 2.03) for beta-blockers. We observed no association with PD risk for either class of medication in terms of duration, dose, number of prescriptions or pattern of use. The weakness of these associations and the absence of additional influence of dose or duration of use argue against any causal interpretation. [ABSTRACT FROM AUTHOR]