Susceptibility to neurofibrillary tangles: role of the PTPRD locus and limited pleiotropy with other neuropathologies.

Tauopathies, including Alzheimer's disease (AD) and other neurodegenerative conditions, are defined by a pathological hallmark: neurofibrillary tangles (NFTs). NFT accumulation is thought to be closely linked to cognitive decline in AD. Here, we perform a genome-wide association study for NFT pathologic burden and report the association of the PTPRD locus (rs560380, P=3.8 × 10-8) in 909 prospective autopsies. The association is replicated in an independent data set of 369 autopsies. The association of PTPRD with NFT is not dependent on the accumulation of amyloid pathology. In contrast, we found that the ZCWPW1 AD susceptibility variant influences NFT accumulation and that this effect is mediated by an accumulation of amyloid ß plaques. We also performed complementary analyses to identify common pathways that influence multiple neuropathologies that coexist with NFT and found suggestive evidence that certain loci may influence multiple different neuropathological traits, including tau, amyloid ß plaques, vascular injury and Lewy bodies. Overall, these analyses offer an evaluation of genetic susceptibility to NFT, a common end point for multiple different pathologic processes.

The association of statin therapy with the risk of recurrent venous thrombosis.

UNLABELLED: Essentials A lowered risk of recurrent venous thrombosis (VT) with statin treatment is controversial. Among observational inception cohort of 2,798 adults with incident VT, 457 had recurrent VT. Time-to-event models with time-varying statin use and adjustment for potential confounders was used for analysis. Compared to nonuse, current statin use was associated with 26% lower risk of recurrent VT. Click to hear Prof. Büller's perspective on Anticoagulant Therapy in the Treatment of Venous Thromboembolism SUMMARY: Background Meta-analyses of randomized controlled trials suggest that treatment with hydroxymethylglutaryl-coenzyme A reductase inhibitors (statins) lowers the risk of incident venous thrombosis (VT), particularly among those without prevalent clinical cardiovascular disease (CVD). Whether this is true for the prevention of recurrent VT is debated. We used an observational inception cohort to estimate the association of current statin use with the risk of recurrent VT. Methods and Results The study setting was a large healthcare organization with detailed medical record and pharmacy information at cohort entry and throughout follow-up. We followed 2798 subjects 18-89 years of age who experienced a validated incident VT between January 1, 2002, and December 31, 2010, for a first recurrent VT, validated by medical record review. During follow-up, 457 (16%) developed a first recurrent VT. In time-to-event models incorporating time-varying statin use and adjusting for potential confounders, current statin use was associated with a 26% lower risk of recurrent VT: hazard ratio 0.74, 95% confidence interval 0.59-0.94. Among cohort members free of CVD (n = 2134), current statin use was also associated with a lower risk (38%) of recurrent VT: hazard ratio 0.62, 95% confidence interval 0.45-0.85. We found similar results when restricting to new users of statins and in subgroups of different statin types and doses. Conclusions In a population-based cohort of subjects who had experienced an incident VT, statin use, compared with nonuse, was associated with a clinically relevant lower risk of recurrent VT. These findings suggest a potential secondary benefit of statins among patients who have experienced an incident VT.

Genetic variation among 82 pharmacogenes: The PGRNseq data from the eMERGE network.

Genetic variation can affect drug response in multiple ways, although it remains unclear how rare genetic variants affect drug response. The electronic Medical Records and Genomics (eMERGE) Network, collaborating with the Pharmacogenomics Research Network, began eMERGE-PGx, a targeted sequencing study to assess genetic variation in 82 pharmacogenes critical for implementation of "precision medicine." The February 2015 eMERGE-PGx data release includes sequence-derived data from ∼5,000 clinical subjects. We present the variant frequency spectrum categorized by variant type, ancestry, and predicted function. We found 95.12% of genes have variants with a scaled Combined Annotation-Dependent Depletion score above 20, and 96.19% of all samples had one or more Clinical Pharmacogenetics Implementation Consortium Level A actionable variants. These data highlight the distribution and scope of genetic variation in relevant pharmacogenes, identifying challenges associated with implementing clinical sequencing for drug treatment at a broader level, underscoring the importance for multifaceted research in the execution of precision medicine.

A genome-wide association study identifies variants in KCNIP4 associated with ACE inhibitor-induced cough.

The most common side effect of angiotensin-converting enzyme inhibitor (ACEi) drugs is cough. We conducted a genome-wide association study (GWAS) of ACEi-induced cough among 7080 subjects of diverse ancestries in the Electronic Medical Records and Genomics (eMERGE) network. Cases were subjects diagnosed with ACEi-induced cough. Controls were subjects with at least 6 months of ACEi use and no cough. A GWAS (1595 cases and 5485 controls) identified associations on chromosome 4 in an intron of KCNIP4. The strongest association was at rs145489027 (minor allele frequency=0.33, odds ratio (OR)=1.3 (95% confidence interval (CI): 1.2-1.4), P=1.0 × 10(-8)). Replication for six single-nucleotide polymorphisms (SNPs) in KCNIP4 was tested in a second eMERGE population (n=926) and in the Genetics of Diabetes Audit and Research in Tayside, Scotland (GoDARTS) cohort (n=4309). Replication was observed at rs7675300 (OR=1.32 (1.01-1.70), P=0.04) in eMERGE and at rs16870989 and rs1495509 (OR=1.15 (1.01-1.30), P=0.03 for both) in GoDARTS. The combined association at rs1495509 was significant (OR=1.23 (1.15-1.32), P=1.9 × 10(-9)). These results indicate that SNPs in KCNIP4 may modulate ACEi-induced cough risk.

Genetic variation in the HLA region is associated with susceptibility to herpes zoster.

Herpes zoster, commonly referred to as shingles, is caused by the varicella zoster virus (VZV). VZV initially manifests as chicken pox, most commonly in childhood, can remain asymptomatically latent in nerve tissues for many years and often re-emerges as shingles. Although reactivation may be related to immune suppression, aging and female sex, most inter-individual variability in re-emergence risk has not been explained to date. We performed a genome-wide association analyses in 22,981 participants (2280 shingles cases) from the electronic Medical Records and Genomics Network. Using Cox survival and logistic regression, we identified a genomic region in the combined and European ancestry groups that has an age of onset effect reaching genome-wide significance (P>1.0 × 10(-8)). This region tags the non-coding gene HCP5 (HLA Complex P5) in the major histocompatibility complex. This gene is an endogenous retrovirus and likely influences viral activity through regulatory functions. Variants in this genetic region are known to be associated with delay in development of AIDS in people infected by HIV. Our study provides further suggestion that this region may have a critical role in viral suppression and could potentially harbor a clinically actionable variant for the shingles vaccine.

Design and anticipated outcomes of the eMERGE-PGx project: a multicenter pilot for preemptive pharmacogenomics in electronic health record systems.

We describe here the design and initial implementation of the eMERGE-PGx project. eMERGE-PGx, a partnership of the Electronic Medical Records and Genomics Network and the Pharmacogenomics Research Network, has three objectives: (i) to deploy PGRNseq, a next-generation sequencing platform assessing sequence variation in 84 proposed pharmacogenes, in nearly 9,000 patients likely to be prescribed drugs of interest in a 1- to 3-year time frame across several clinical sites; (ii) to integrate well-established clinically validated pharmacogenetic genotypes into the electronic health record with associated clinical decision support and to assess process and clinical outcomes of implementation; and (iii) to develop a repository of pharmacogenetic variants of unknown significance linked to a repository of electronic health record-based clinical phenotype data for ongoing pharmacogenomics discovery. We describe site-specific project implementation and anticipated products, including genetic variant and phenotype data repositories, novel variant association studies, clinical decision support modules, clinical and process outcomes, approaches to managing incidental findings, and patient and clinician education methods.

Nonsteroidal anti-inflammatory drugs are associated with increased neuritic plaques.

OBJECTIVES: Observational and experimental studies suggest that nonsteroidal anti-inflammatory drugs (NSAIDs) may protect against Alzheimer disease (AD); however, clinical trials and other observational studies, including the Adult Changes in Thought (ACT) study, show no protection or promotion of AD. The objective of this study is to determine the relationship between common dementia-associated pathologies and mid- to late-life NSAID exposure. METHODS: We examined the association of mid- to late-life NSAID use with neuropathologic findings on 257 autopsies from ACT, a population-based study of brain aging and incident dementia. Cumulative standard daily doses (SDD) of nonselective NSAIDs were determined from ≥10 years of computerized pharmacy dispensing data. Analyses were adjusted for selection bias to broaden generalizability of results to 3,026 eligible participants in the ACT cohort. Seven pathologic indices were evaluated: intermediate or frequent score for neuritic plaques, Braak stages V or VI for neurofibrillary tangles, >2 cerebral microinfarcts, the presence of any neocortical Lewy bodies, any macroscopic infarcts, any amyloid angiopathy, and moderate or severe atherosclerosis. RESULTS: Of the neuropathologic indices evaluated, only neuritic plaque score was significantly increased in participants with greater use of nonselective NSAIDs (p = 0.065), specifically in those with high levels of cumulative use: 1,000-2,000 SDD (adjusted relative risk [RR] 2.16, 95% confidence interval [CI] 1.02-4.25, compared to light/nonuse [<60 SDD]) and >2,000 SDD (adjusted RR 2.37, 95% CI 1.24-4.67). CONCLUSIONS: Increased neuritic plaque accumulation may explain the association between heavy use of nonselective NSAIDs and increased risk of dementia among ACT participants.

Association between late-life body mass index and dementia: The Kame Project.

OBJECTIVE: To examine the association between body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR) and risk of dementia and its subtypes in late life. METHODS: Participants were members of the Kame Project, a population-based prospective cohort study of 1,836 Japanese Americans living in King County, WA, who had a mean age of 71.8 years and were dementia-free at baseline (1992-1994), and were followed for incident dementia through 2001. Cox proportional hazards models were used to estimate the risk of dementia, Alzheimer disease (AD), and vascular dementia (VaD) controlling for demographic and lifestyle characteristics and vascular comorbidities as a function of baseline BMI, WC, and WHR and change in BMI over time. RESULTS: Higher baseline BMI was significantly associated with a reduced risk of AD (hazard ratio [HR] = 0.56, 95% confidence interval [CI] = 0.33-0.97) in the fully adjusted model. Slower rate of decline in BMI was associated with a reduced risk of dementia (HR = 0.37, 95% CI = 0.14-0.98), with the association stronger for those who were overweight or obese (HR = 0.18, 95% CI = 0.05-0.58) compared to normal or underweight (HR = 1.00, 95% CI = 0.18-5.66) at baseline. CONCLUSION: Higher baseline body mass index (BMI) and slower declining BMI in late life are associated with a reduced risk of dementia, suggesting that low BMI or a faster decline in BMI in late life may be preclinical indicators of an underlying dementing illness, especially for those who were initially overweight or obese.

Risk of dementia and AD with prior exposure to NSAIDs in an elderly community-based cohort.

BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) may prevent Alzheimer dementia (AD). METHODS: We analyzed the association of prior NSAID exposure with incident dementia and AD in the Adult Changes in Thought population-based cohort aged > or = 65 years (median 74.8) at enrollment. Participants were members of Group Health, which provided computerized pharmacy dispensing records from 1977 onward. We studied 2,736 dementia-free enrollees with extensive prior pharmacy data, following them biennially for up to 12 years to identify dementia and AD. Cox proportional hazards regression assessed association of dementia or AD with NSAID use graded in standard daily doses (SDD) dispensed over 2 years (e.g., heavy use = 500 + SDD), with some analyses also adding consecutive biennial self-reports of NSAID use. RESULTS: Pharmacy records identified 351 participants (12.8%) with history of heavy NSAID use at enrollment. Another 107 became heavy users during follow-up. Some 476 individuals developed incident dementia, 356 with AD (median onset ages 83.5 and 83.8 years). Contrary to the hypothesis that NSAIDs protect against AD, pharmacy-defined heavy NSAID users showed increased incidence of dementia and AD, with adjusted hazard ratios of 1.66 (95% confidence interval, 1.24-2.24) and 1.57 (95% confidence interval, 1.10-2.23). Addition of self-reported exposure data did not alter these results. CONCLUSIONS: These findings differ from those of other studies with younger cohorts. The results observed elsewhere may reflect delayed onset of Alzheimer dementia (AD) in nonsteroidal anti-inflammatory drug (NSAID) users. Conceivably, such delay could result in increased AD incidence in late old age. The relation of NSAID use and AD pathogenesis needs further investigation.

Statin therapy is associated with reduced neuropathologic changes of Alzheimer disease.

BACKGROUND: Treatment with 3-hydroxy-3-methylglutaryl-coenzyme-A reductase inhibitors ("statins") has been associated in some epidemiologic studies with reduced risk of Alzheimer disease (AD). However, direct evidence of statin effects on neuropathologic markers of AD is lacking. We investigated whether antecedent statin exposure is associated with neuritic plaque (NP) or neurofibrillary tangle (NFT) burden in a population-based sample of human subjects. METHODS: Brain autopsies were performed on 110 subjects, ages 65 to 79 years, who were cognitively normal at enrollment into the Adult Changes in Thought Study. Neuropathologic findings were compared between statin users with > or =3 prescriptions of > or =15 pills of simvastatin, pravastatin, lovastatin, or atorvastatin vs nonusers, based on pharmacy dispensing records. RESULTS: After controlling for age at death, gender, cognitive function at study entry, brain weight, and presence of cerebral microvascular lesions, the odds ratio (OR) for each unit increase in Braak NFT stage in statin users vs nonusers was 0.44 (95% CI: 0.20 to 0.95). The OR for each unit increase in Consortium to Establish a Registry for Alzheimer's Disease (CERAD) staging of NPs did not deviate significantly from unity (OR 0.69; 95% CI: 0.32 to 1.52). However, the risk for typical AD pathology (Braak stage > or = IV and CERAD rating > or = moderate) was reduced in statin users (OR 0.20; 95% CI: 0.05 to 0.86). CONCLUSIONS: These findings demonstrate an association between antecedent statin use and neurofibrillary tangle burden at autopsy. Additional study is needed to examine whether statin use may be causally related to decreased development of Alzheimer disease-related neuropathologic changes.

Serum cholesterol and risk of Alzheimer disease: a community-based cohort study.

OBJECTIVES: To examine the association of serum total cholesterol (TC) and high density lipoprotein (HDL) levels and subsequent incidence of dementia and Alzheimer disease (AD) in a population-based cohort study. METHODS: A cohort of cognitively intact persons, aged 65 and older, was randomly selected from Group Health Cooperative (GHC), a large health maintenance organization, and was assessed biennially for dementia. Premorbid levels of TC and HDL were obtained from a computerized clinical laboratory database at GHC. Cox proportional hazards regression was used to calculate hazard ratios (HR, 95% CI) for dementia and AD associated with quartiles of TC and HDL levels. RESULTS: Of the 2,356 eligible participants, 2,141 had at least one serum TC measure prior to the initial enrollment. Using the lowest TC quartiles as the reference group, the HR in the highest TC quartiles was not significantly elevated for dementia (1.16, 0.81 to 1.67) or for AD (1.00, 0.61 to 1.62) after adjusting for age, sex, education, baseline cognition, vascular comorbidities, body mass index, and lipid-lowering agent use. Serum HDL showed a similar lack of significant association with risk of dementia or AD. Models that included the presence of one or more APOE-epsilon4 alleles showed a typical association of epsilon4 with AD risk. This association was not materially modified by inclusion of TC level. CONCLUSION: The data do not support an association between serum total cholesterol or high density lipoprotein in late life and subsequent risk of dementia or Alzheimer disease (AD). The increased risk of AD with APOE-epsilon4 is probably not mediated by serum total cholesterol levels.

Cognitive differences in dementia patients with autopsy-verified AD, Lewy body pathology, or both.

OBJECTIVE: To examine the neuropsychological profile of dementia patients from a community-based autopsy sample of dementia, comparing Alzheimer disease (AD), Lewy body pathology (LBP) alone, and LBP with coexistent AD (AD/LBP). METHODS: The authors reviewed 135 subjects from a community-based study of dementia for whom autopsy and brain tissue was available. Diagnostic groups were determined according to standard neuropathologic methods and criteria, and the presence of LBs was determined using alpha-synuclein immunostaining. Neuropathologically defined diagnostic groups of AD, AD/LBP, and LBP were examined for differences on neuropsychological test performance at the time of initial study enrollment. RESULTS: There were 48 patients with AD alone, 65 with LB and AD pathology (AD/LBP), and 22 with LBP alone (LBP alone). There were no significant differences between groups demographically or on performance of enrollment Mini-Mental State Examination (MMSE) or Dementia Rating Scale (DRS). AD patients performed worse than the LBP patients on memory measures (Fuld Object Memory Evaluation Delayed Recall, Wechsler Memory Scale Logical Memory Immediate and Delayed Recall; p < 0.05) and a naming task (Consortium to Establish a Registry for Alzheimer's Disease Naming; p < 0.05). LBP patients were more impaired than AD patients on executive function (Trail Making Test Part B; p < 0.05) and attention tasks (Wechsler Adult Intelligence Scale-Revised Digit Span; p < 0.05). Decline in MMSE and DRS scores over time were greatest in the patients with AD/LBP. CONCLUSIONS: In a community-based sample of older, medically complicated patients with dementia, there are neuropsychological differences between dementia subtypes at the time of diagnosis. In particular, patients with Alzheimer disease (AD) alone and AD/Lewy body pathology (LBP) had more severe memory impairment than patients with LBP. LBP alone was associated with more severe executive dysfunction. Patients with AD/LBP had the most rapid rate of cognitive decline.

Crossing to safety: transforming healthcare organizations for patient safety.

The current healthcare system is not designed to ensure better patient safety. In addition, healthcare is simultaneously becoming increasingly complex and increasingly fragmented. Medical knowledge and technology are expanding at an incredible rate, making it difficult for the healthcare providers to keep pace with advancing knowledge. Patients' needs are changing too: shifting from the diagnosis and treatment of a single, acute problem to the long-term management of multiple, interrelated chronic conditions. Our systems of care are not keeping up with these changes and, consequently, patients are experiencing unnecessary risk. Improving patient safety requires a transformation in how we currently care for patients. Healthcare organizations must adopt a new paradigm of care that holds patient safety as a core value and practice. To achieve this aim, healthcare organizations should build and maintain a culture of patient safety, provide leadership for patient safety that establishes a blame-free environment, proactively survey and monitor for adverse events, continually engineer patient safety into healthcare processes, and provide information and communication technologies to support patient safety.

Statin therapy and risk of dementia in the elderly: a community-based prospective cohort study.

OBJECTIVE: To assess the association between statin therapy and risk of Alzheimer disease (AD) in a prospective cohort study with documented statin exposure and incident dementia. METHODS: This is a prospective, cohort study of statin use and incident dementia and probable AD. A cohort of 2,356 cognitively intact persons, aged 65 and older, were randomly selected from a health maintenance organization (HMO), and were assessed biennially for dementia. Statin use was identified using the HMO pharmacy database. A proportional hazards model with statin use as a time-dependent covariate was used to assess the statin-dementia/AD association. RESULTS: Among 312 participants with incident dementia, 168 had probable AD. The unadjusted hazard ratios (HRs) with statin use were 1.33 (95% CI 0.95 to 1.85) for all-cause dementia and 0.90 (CI 0.54 to 1.51) for probable AD. Adjusted corresponding HRs were 1.19 (CI 0.82 to 1.75) and 0.82 (CI 0.46 to 1.46). A subgroup analysis of participants with at least one APOE-epsilon4 allele who entered the study before age 80 produced an adjusted HR of 0.33 (CI 0.10 to 1.04). CONCLUSION: Employing time-dependent proportional hazards modeling, the authors found no significant association between statin use and incident dementia or probable AD. In contrast, when the data were analyzed, inappropriately, as a case-control study, the authors found an OR of 0.55 for probable AD, falsely indicating a protective effect of statins. Study design and analytic methods may explain the discrepancy between the current null findings and earlier findings.

Head circumference and incident Alzheimer's disease: modification by apolipoprotein E.

BACKGROUND: The clinical expression of AD likely occurs when the accumulation of degeneration in specific brain regions leads to the descent below a critical threshold of "brain reserve" beyond which normal cognitive function cannot be maintained. The association between head circumference (HC), a measure of brain reserve, and the incidence of probable AD was examined in a large nondemented cohort that has been followed since 1992 and its modification by APOE epsilon 4 genotype. METHODS: Fifty-nine incident cases of probable AD were identified from 1,869 initially nondemented individuals seen at the baseline examination (1992 to 1994) and followed for a mean of 3.8 years. Variables measured at baseline included age, education, gender, HC, height, weight, and score on the National Adult Reading Test-Revised. APOE was genotyped at the time of the first biennial examination (1994 to 1996) and was available for 1,111 individuals in the cohort. Cox proportional hazard regression was performed to estimate hazard ratios (HR) for probable AD for HC and other covariates. RESULTS: Incident cases were significantly older, less educated, shorter, and lighter, had lower estimated verbal IQ scores, and were more likely to have at least one APOE epsilon 4 allele than unaffected individuals. The HR associated with the lowest tertile of HC (<21.4 inches) adjusted for education, gender, and APOE epsilon 4 was 2.3 (95% CI 0.7 to 6.9, p = 0.16). The HR for one or two APOE epsilon 4 alleles was significant (HR = 4.8, 95% CI 1.8 to 12.9, p = 0.002). The combination of low HC and APOE epsilon 4 strongly predicted earlier onset of AD with HR = 14.1 (95% CI 3.0 to 65, p = 0.0007). CONCLUSIONS: Smaller HC, in the presence of the APOE epsilon 4 allele, hastens the age at onset of AD. These results support the brain reserve hypothesis and its importance in precipitating the clinical expression of AD among genetically predisposed individuals.

Healthcare utilization and costs in managed care patients with Alzheimer's disease during the last few years of life.

OBJECTIVES: To learn whether managed care patients with Alzheimer's disease (AD) are more or less costly to care for than patients with other forms of dementia or patients without dementia during the last few years of life. DESIGN: Case control study. SETTING: A health maintenance organization base population. PARTICIPANTS: Three groups of subjects (mean age 85) who were deceased members of a dementia registry obtained from a health maintenance organization base population: 263 subjects with clinically diagnosed probable AD, 133 subjects with other forms of dementia, and 100 cognitively intact controls. MEASUREMENTS: Utilization records were examined for the 3 years preceding death. RESULTS: In all subcategories and in aggregate, utilization and costs of care were either similar or lower for patients with AD than for the other groups, even after controlling for age, gender, and comorbidity. CONCLUSIONS: Persons with AD do not incur higher costs than persons with other types of dementia or age-matched persons without dementia in a mature health maintenance organization during the last few years of life, when utilization is likely to be highest.

Alcohol, aging, and cognitive performance in a cohort of Japanese Americans aged 65 and older: the Kame project.

OBJECTIVE: To investigate the effects of light to moderate alcohol consumption on cognitive performance. DESIGN AND SETTING: A cross-sectional analysis including older Japanese Americans in King County, WA, enrolled in the Kame Project, a population-based study of cognition, dementia, and aging. PARTICIPANTS: 1,836 cognitively intact participants aged 65 and older who participated in the baseline (1992-1994) examination. MEASUREMENT: Cognitive performance was measured using the Cognitive Abilities Screening Instrument, reaction time (simple and choice), and a measure of vocabulary (North American Adult Reading Test). RESULTS: Multivariate analyses were used to examine the relationship between cognitive performance and alcohol consumption at baseline with men and women together and then separately controlling for age, education, smoking, history of stroke, angina, hypertension, diabetes, and coronary heart disease. Findings showed lower cognitive test scores were observed for men who were either abstainers or in the heavy drinking group. For women, a linear relationship between alcohol consumption and cognitive performance was seen on two of the four measures of cognitive functioning. No significant difference in the association of drinking and cognitive function was identified within the different Japanese American subgroups. CONCLUSION: RESULTS suggest a possible positive relationship between light to moderate drinking and cognitive performance in an aging Japanese American population. Additional long-term prospective and cross-cultural studies are needed to determine the generalizability of these findings to other aging cohorts.