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1.
Brain ; 144(7): 2166-2175, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-33742668

RESUMO

The ageing brain is vulnerable to a wide array of neuropathologies. Prior work estimated that the three most studied of these, Alzheimer's disease, infarcts, and Lewy bodies, account for ∼40% of the variation in late life cognitive decline. However, that estimate did not incorporate many other diseases that are now recognized as potent drivers of cognitive decline [e.g. limbic predominant age-related TDP-43 encephalopathy (LATE-NC), hippocampal sclerosis, other cerebrovascular conditions]. We examined the degree to which person-specific cognitive decline in old age is driven by a wide array of neuropathologies. Deceased participants (n = 1164) from two longitudinal clinical-pathological studies, the Rush Memory and Aging Project and Religious Orders Study, completed up to 24 annual evaluations including 17 cognitive performance tests and underwent brain autopsy. Neuropathological examinations provided 11 pathological indices, including markers of Alzheimer's disease, non- Alzheimer's disease neurodegenerative diseases (i.e. LATE-NC, hippocampal sclerosis, Lewy bodies), and cerebrovascular conditions (i.e. macroscopic infarcts, microinfarcts, cerebral amyloid angiopathy, atherosclerosis, and arteriolosclerosis). Mixed effects models examined the linear relation of pathological indices with global cognitive decline, and random change point models examined the relation of the pathological indices with the onset of terminal decline and rates of preterminal and terminal decline. Cognition declined an average of about 0.10 unit per year (estimate = -0.101, SE = 0.003, P < 0.001) with considerable heterogeneity in rates of decline (variance estimate for the person-specific slope of decline was 0.0094, P < 0.001). When considered separately, 10 of 11 pathological indices were associated with faster decline and accounted for between 2% and 34% of the variation in decline, respectively. When considered simultaneously, the 11 pathological indices together accounted for 43% of the variation in decline; Alzheimer's disease-related indices accounted for 30-36% of the variation, non-Alzheimer's disease neurodegenerative indices 4-10%, and cerebrovascular indices 3-8%. Finally, the 11 pathological indices combined accounted for less than a third of the variation in the onset of terminal decline (28%) and rates of preterminal (32%) and terminal decline (19%). Although age-related neuropathologies account for a large proportion of the variation in late life cognitive decline, considerable variation remains unexplained even after considering a wide array of neuropathologies. These findings highlight the complexity of cognitive ageing and have important implications for the ongoing effort to develop effective therapeutics and identify novel treatment targets.


Assuntos
Doença de Alzheimer/epidemiologia , Doenças Arteriais Cerebrais/epidemiologia , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Doenças Neurodegenerativas/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Doença de Alzheimer/patologia , Encéfalo/patologia , Doenças Arteriais Cerebrais/complicações , Doenças Arteriais Cerebrais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Neurodegenerativas/complicações , Doenças Neurodegenerativas/patologia
2.
Hum Brain Mapp ; 42(6): 1794-1804, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33471942

RESUMO

The role of massa intermedia (MI) is poorly understood in humans. Recent studies suggest its presence may play a role in normal human neurocognitive function while prior studies have shown the absence of MI correlated with psychiatric disorders. There is growing evidence that MI is likely a midline white matter conduit, responsible for interhemispheric connectivity, similar to other midline commissures. MI presence was identified in an unrelated sample using the Human Connectome Project database. MI structural connectivity maps were created and gray matter target regions were identified using probabilistic tractography of the whole brain. Probabilistic tractography revealed an extensive network of connections between MI and limbic, frontal and temporal lobes as well as insula and pericalcarine cortices. Women compared to men had stronger connectivity via their MI. The presented results support the role of MI as a midline commissure with strong connectivity to the amygdala, hippocampus, and entorhinal cortex.


Assuntos
Córtex Cerebral , Imagem de Tensor de Difusão , Substância Cinzenta , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/patologia , Tálamo , Adulto , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/diagnóstico por imagem , Substância Cinzenta/anatomia & histologia , Substância Cinzenta/diagnóstico por imagem , Humanos , Fatores Sexuais , Tálamo/anatomia & histologia , Tálamo/diagnóstico por imagem , Adulto Jovem
3.
Cochrane Database Syst Rev ; 10: CD013870, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34709669

RESUMO

BACKGROUND: Atopic eczema (AE), also known as atopic dermatitis, is a chronic inflammatory skin condition that causes significant burden. Phototherapy is sometimes used to treat AE when topical treatments, such as corticosteroids, are insufficient or poorly tolerated. OBJECTIVES: To assess the effects of phototherapy for treating AE. SEARCH METHODS: We searched the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, and ClinicalTrials.gov to January 2021. SELECTION CRITERIA: We included randomised controlled trials in adults or children with any subtype or severity of clinically diagnosed AE. Eligible comparisons were any type of phototherapy versus other forms of phototherapy or any other treatment, including placebo or no treatment. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodology. For key findings, we used RoB 2.0 to assess bias, and GRADE to assess certainty of the evidence. Primary outcomes were physician-assessed signs and patient-reported symptoms. Secondary outcomes were Investigator Global Assessment (IGA), health-related quality of life (HRQoL), safety (measured as withdrawals due to adverse events), and long-term control. MAIN RESULTS: We included 32 trials with 1219 randomised participants, aged 5 to 83 years (mean: 28 years), with an equal number of males and females. Participants were recruited mainly from secondary care dermatology clinics, and study duration was, on average, 13 weeks (range: 10 days to one year). We assessed risk of bias for all key outcomes as having some concerns or high risk, due to missing data, inappropriate analysis, or insufficient information to assess selective reporting. Assessed interventions included: narrowband ultraviolet B (NB-UVB; 13 trials), ultraviolet A1 (UVA1; 6 trials), broadband ultraviolet B (BB-UVB; 5 trials), ultraviolet AB (UVAB; 2 trials), psoralen plus ultraviolet A (PUVA; 2 trials), ultraviolet A (UVA; 1 trial), unspecified ultraviolet B (UVB; 1 trial), full spectrum light (1 trial), Saalmann selective ultraviolet phototherapy (SUP) cabin (1 trial), saltwater bath plus UVB (balneophototherapy; 1 trial), and excimer laser (1 trial). Comparators included placebo, no treatment, another phototherapy, topical treatment, or alternative doses of the same treatment. Results for key comparisons are summarised (for scales, lower scores are better): NB-UVB versus placebo/no treatment There may be a larger reduction in physician-assessed signs with NB-UVB compared to placebo after 12 weeks of treatment (mean difference (MD) -9.4, 95% confidence interval (CI) -3.62 to -15.18; 1 trial, 41 participants; scale: 0 to 90). Two trials reported little difference between NB-UVB and no treatment (37 participants, four to six weeks of treatment); another reported improved signs with NB-UVB versus no treatment (11 participants, nine weeks of treatment). NB-UVB may increase the number of people reporting reduced itch after 12 weeks of treatment compared to placebo (risk ratio (RR) 1.72, 95% CI 1.10 to 2.69; 1 trial, 40 participants). Another trial reported very little difference in itch severity with NB-UVB (25 participants, four weeks of treatment). The number of participants with moderate to greater global improvement may be higher with NB-UVB than placebo after 12 weeks of treatment (RR 2.81, 95% CI 1.10 to 7.17; 1 trial, 41 participants). NB-UVB may not affect rates of withdrawal due to adverse events. No withdrawals were reported in one trial of NB-UVB versus placebo (18 participants, nine weeks of treatment). In two trials of NB-UVB versus no treatment, each reported one withdrawal per group (71 participants, 8 to 12 weeks of treatment). We judged that all reported outcomes were supported with low-certainty evidence, due to risk of bias and imprecision. No trials reported HRQoL. NB-UVB versus UVA1 We judged the evidence for NB-UVB compared to UVA1 to be very low certainty for all outcomes, due to risk of bias and imprecision. There was no evidence of a difference in physician-assessed signs after six weeks (MD -2.00, 95% CI -8.41 to 4.41; 1 trial, 46 participants; scale: 0 to 108), or patient-reported itch after six weeks (MD 0.3, 95% CI -1.07 to 1.67; 1 trial, 46 participants; scale: 0 to 10). Two split-body trials (20 participants, 40 sides) also measured these outcomes, using different scales at seven to eight weeks; they reported lower scores with NB-UVB. One trial reported HRQoL at six weeks (MD 2.9, 95% CI -9.57 to 15.37; 1 trial, 46 participants; scale: 30 to 150). One split-body trial reported no withdrawals due to adverse events over 12 weeks (13 participants). No trials reported IGA. NB-UVB versus PUVA We judged the evidence for NB-UVB compared to PUVA (8-methoxypsoralen in bath plus UVA) to be very low certainty for all reported outcomes, due to risk of bias and imprecision. There was no evidence of a difference in physician-assessed signs after six weeks (64.1% reduction with NB-UVB versus 65.7% reduction with PUVA; 1 trial, 10 participants, 20 sides). There was no evidence of a difference in marked improvement or complete remission after six weeks (odds ratio (OR) 1.00, 95% CI 0.13 to 7.89; 1 trial, 9/10 participants with both treatments). One split-body trial reported no withdrawals due to adverse events in 10 participants over six weeks. The trials did not report patient-reported symptoms or HRQoL. UVA1 versus PUVA There was very low-certainty evidence, due to serious risk of bias and imprecision, that PUVA (oral 5-methoxypsoralen plus UVA) reduced physician-assessed signs more than UVA1 after three weeks (MD 11.3, 95% CI -0.21 to 22.81; 1 trial, 40 participants; scale: 0 to 103). The trial did not report patient-reported symptoms, IGA, HRQoL, or withdrawals due to adverse events. There were no eligible trials for the key comparisons of UVA1 or PUVA compared with no treatment. Adverse events Reported adverse events included low rates of phototoxic reaction, severe irritation, UV burn, bacterial superinfection, disease exacerbation, and eczema herpeticum. AUTHORS' CONCLUSIONS: Compared to placebo or no treatment, NB-UVB may improve physician-rated signs, patient-reported symptoms, and IGA after 12 weeks, without a difference in withdrawal due to adverse events. Evidence for UVA1 compared to NB-UVB or PUVA, and NB-UVB compared to PUVA was very low certainty. More information is needed on the safety and effectiveness of all aspects of phototherapy for treating AE.


Assuntos
Dermatite Atópica , Eczema , Terapia Ultravioleta , Adulto , Criança , Dermatite Atópica/tratamento farmacológico , Feminino , Humanos , Masculino , Fototerapia , Qualidade de Vida
4.
Photodermatol Photoimmunol Photomed ; 37(2): 99-104, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33471377

RESUMO

Pellagra is a clinical syndrome caused by a deficiency of niacin (nicotinic acid) and/or its precursor tryptophan. The cardinal manifestations are 4 D's: dermatitis, diarrhoea, dementia and in worst case death. Increased use of isoniazid prophylaxis along with antiretroviral therapy in countries where latent tuberculosis is common has been associated with increased presentations with pellagra.


Assuntos
Antituberculosos/efeitos adversos , Isoniazida/efeitos adversos , Pelagra/etiologia , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Infecções por HIV/tratamento farmacológico , Humanos , Pelagra/induzido quimicamente
5.
Alzheimers Dement ; 17(12): 1923-1937, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34060702

RESUMO

INTRODUCTION: We identified a "cognitive clock," a novel indicator of brain health that provides person-specific estimates of cognitive age, and tested the hypothesis that cognitive age is a better predictor of brain health than chronological age in two independent datasets. METHODS: The initial analyses were based on 1057 participants from the Rush Memory and Aging Project and the Religious Orders Study who began without impairment and underwent cognitive assessments up to 24 years. A shape invariant model characterized the latent pattern of cognitive decline, conceptualized here as the "cognitive clock," and yielded person-specific estimates of cognitive age. Survival analyses examined cognitive versus chronological age for predicting Alzheimer's disease dementia, mild cognitive impairment and mortality, and regression analyses examined associations of cognitive versus chronological age with neuropathology and brain atrophy. Finally, we applied the cognitive clock to an independent validation sample of 2592 participants from the Chicago Health and Aging Project, a biracial population-based study, to confirm the predictive utility of cognitive age. RESULTS: The "cognitive clock" showed that cognition remained stable until a cognitive age of about 80, then declined moderately until 90, then declined precipitously. In the initial dataset, cognitive age was a better predictor of dementia, mild cognitive impairment and mortality than chronological age, and was more strongly associated with neuropathology and brain atrophy. Application of the cognitive clock to the independent validation sample provided further support for the utility of cognitive age as a strong prognostic indicator of adverse outcomes. DISCUSSION: Cognitive age is a robust prognostic indicator of adverse health outcomes and may serve as a useful biomarker in aging research.


Assuntos
Envelhecimento Cognitivo/fisiologia , Disfunção Cognitiva/patologia , Demência/patologia , Idoso , Atrofia/patologia , Autopsia , Encéfalo/patologia , Chicago , Disfunção Cognitiva/etnologia , Demência/etnologia , Humanos , Estudos Longitudinais , Mortalidade/tendências , Neuropatologia , Estados Unidos
6.
Photodermatol Photoimmunol Photomed ; 36(2): 90-96, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31518445

RESUMO

BACKGROUND: Although used for decades in psoriasis, access to phototherapy is becoming increasingly restricted. Besides patient inconvenience, this is in large part to do with a perception of "high cost." We previously reported a comprehensive analysis of direct and indirect phototherapy treatment cost. However, no robust data exist on the actual savings associated with providing phototherapy in the treatment pathway. OBJECTIVES: To quantify the cost savings achieved by phototherapy by delaying alternative treatments. METHODS: Costs accruing through the UK-wide established treatment pathway with and without phototherapy were analysed. Direct and indirectly incurred drug treatment costs were calculated using drug tariff, laboratory cost, estate rates and clinic review costs. To enhance reliability, ranges of cost scenarios were calculated by varying parameters such as drug dosing. RESULTS: Medium annual cost savings per patient were £2200 [range: £1800-£2900] for NB-UVB, and £3700 [range: £2500-£5300] if both NB-UVB and PUVA courses were administered, respectively. As the provider treated 656 ± 76 patients per year during the 6-year observational window, this amounted to savings of £Mio 2.4 [range: £Mio 1.6-£Mio 3.4], even excluding additional non-modelled drug-associated costs (eg diagnostics, adverse event management). Since we only consider cost savings by delay of drug treatment for the duration of phototherapy, drug price reductions through biosimilar introduction only have a small effect. We provide spreadsheets allowing adaptation cost savings projections by varying input variables. CONCLUSIONS: Healthcare providers may achieve significant cost savings by implementing and/or widening access to phototherapy.


Assuntos
Redução de Custos , Fototerapia/economia , Psoríase , Tempo para o Tratamento/economia , Custos e Análise de Custo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/tratamento farmacológico , Psoríase/economia , Reino Unido
7.
Neurocrit Care ; 33(2): 552-564, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32072457

RESUMO

BACKGROUND/OBJECTIVE: Diffusion weighted imaging (DWI) lesions have been well described in patients with acute spontaneous intracerebral hemorrhage (sICH). However, there are limited data on the influence of these lesions on sICH functional outcomes. We conducted a prospective observational cohort study with blinded imaging and outcomes assessment to determine the influence of DWI lesions on long-term outcomes in patients with acute sICH. We hypothesized that DWI lesions are associated with worse modified Rankin Scale (mRS) at 3 months after hospital discharge. METHODS: Consecutive sICH patients meeting study criteria were consented for an magnetic resonance imaging (MRI) scan of the brain and evaluated for remote DWI lesions by neuroradiologists blinded to the patients' hospital course. Blinded mRS outcomes were obtained at 3 months. Logistic regression was used to determine significant factors (p < 0.05) associated with worse functional outcomes defined as an mRS of 4-6. The generalized estimating equation (GEE) approach was used to investigate the effect of DWI lesions on dichotomized mRS (0-3 vs 4-6) longitudinally. RESULTS: DWI lesions were found in 60 of 121 patients (49.6%). The presence of a DWI lesion was associated with increased odds for an mRS of 4-6 at 3 months (OR 5.987, 95% CI 1.409-25.435, p = 0.015) in logistic regression. Using the GEE model, patients with a DWI lesion were less likely to recover over time between 14 days/discharge and 3 months (p = 0.005). CONCLUSIONS: DWI lesions are common in primary sICH, occurring in almost half of our cohort. Our data suggest that DWI lesions are associated with worse mRS at 3 months in good grade sICH and are predictive of impaired recovery after hospital discharge. Further research into the pathophysiologic mechanisms underlying DWI lesions may lead to novel treatment options that may improve outcomes associated with this devastating disease.


Assuntos
Isquemia Encefálica , Hemorragia Cerebral , Encéfalo , Hemorragia Cerebral/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Humanos , Estudos Prospectivos
8.
Alzheimers Dement ; 16(1): 209-218, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31914231

RESUMO

INTRODUCTION: Reduced hippocampal volume is associated with late-life cognitive decline, but prior studies have not determined whether this association persists after accounting for Alzheimer's disease (AD) and other neuropathologies. METHODS: Participants were 531 deceased older adults from community-based cohort studies of aging who had undergone annual cognitive evaluations. At death, brain tissue underwent neuropathologic examination and magnetic resonance imaging (MRI). Linear mixed models examined whether hippocampal volume measured via MRI accounted for variation in decline rate of global cognition and five cognitive domains, above and beyond neuropathologic indices. RESULTS: Demographics and indices of AD, cerebrovascular disease, Lewy body disease, hippocampal sclerosis, TDP-43, and atherosclerosis accounted for 42.6% of the variation in global cognitive decline. Hippocampal volume accounted for an additional 5.4% of this variation and made similar contributions in four of the five cognitive domains. DISCUSSION: Hippocampal volume is associated with late-life cognitive decline, above and beyond contributions from common neuropathologic indices.


Assuntos
Envelhecimento , Disfunção Cognitiva/patologia , Hipocampo/patologia , Neuropatologia , Idoso , Envelhecimento/patologia , Encéfalo/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Lobo Temporal/patologia
9.
Hippocampus ; 29(5): 468-478, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30588711

RESUMO

Parametric subtracted post-ictal diffusion tensor imaging (pspiDTI) is a novel imaging technique developed at our center to visualize transient, patient-specific, ictal-associated water diffusion abnormalities in hippocampal-associated axonal tissue. PspiDTI can elucidate putative connectivity patterns, tracing ictal propagation following a partial-onset seizure without generalization secondarily. PspiDTI compares two DTI volumes acquired during the early post-ictal period (<4 hr), and baseline inter-ictal interval (>24 hr post-seizure). This technique performs a voxel-wise parametric test to identify statistically significant transient ictal-associated changes in water diffusivity involving white matter (WM). Our technique was applied to six patients with refractory partial-onset epilepsy who were candidates for direct cortical responsive neurostimulation (RNS) therapy. Global and region-specific fractional anisotropy decreases, relative to baseline, were detected in all patients with a 17.01% (p < .01) relative mean decrement, while trace increases were found in 6/6 (100%) patients with a 13.30% (p < .01) relative global mean increment. Changes in diffusivity were anatomically compared with transient hyper-perfusion as detected by subtracted ictal SPECT co-registered to MRI (SISCOM). In 5/6 (83.33%) patients, alterations in WM diffusivity were detected adjacent to the SISCOM signal localized predominantly in gray matter. In 4/6 patients, post-implant RNS electrocorticography revealed early ictal propagation between implanted RNS depth leads guided by pspiDTI, hence validating concordant abnormal diffusivity regions detected by our technique. PspiDTI can complement the conventional pre-surgical evaluation to provide additional crucial information regarding WM ictal-propagation pathways between predominantly gray matter ictal-onset zones. When incorporated into a multi-modality pre-surgical workflow, pspiDTI can aid in defining critical nodes between ictogenic regions. This information can be used to strategically implant a limited set of two RNS depth leads for maximizing the extent to which direct cortical RNS can modulate a potentially extensive epileptogenic network.


Assuntos
Imagem de Tensor de Difusão/métodos , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/terapia , Terapia por Estimulação Elétrica/métodos , Neuroimagem/métodos , Adulto , Epilepsias Parciais/diagnóstico por imagem , Epilepsias Parciais/terapia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Cirurgia Assistida por Computador , Adulto Jovem
15.
Arthroscopy ; 35(3): 734-740, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30733040

RESUMO

PURPOSE: To evaluate clinical measurements of glenoid bone loss based on 3-dimensional (3D) computed tomography (CT) and automatically segmented 3D reconstructions from Dixon fat-water magnetic resonance (MR) imaging. METHODS: Available CT and MR studies from 16 patients with recurrent anterior shoulder instability were retrospectively reviewed. Three-dimensional reconstructions were formed independently by 2 observers using freely available software and a simple threshold-based segmentation (3D Slicer, version 4.8.0; http://www.slicer.org). Bone loss was estimated with the perfect-circle method. Intra-user and interuser reproducibility was determined with intraclass correlation coefficients. Bland-Altman plots were used to evaluate the similarity between imaging modalities. RESULTS: Differences between MR and CT estimates of bone loss ranged from 0% to 6%. The individual intraclass correlation coefficients showed good to excellent reliability, with intraobserver comparisons between MR- and CT-based bone loss estimates ranging from 0.94 to 0.99. Bland-Altman plots showed 95% confidence intervals from -5% to 6% for differences between MR and CT estimates, with 88% of all measurements (42 of 48) showing a less than 2% difference between MR and CT estimates. CONCLUSIONS: The described methodology for obtaining an MR-based 3D reconstruction of the glenoid can evaluate glenoid bone loss similarly to the performance of a 3D CT reconstruction. The results may allow surgeons to simplify the preoperative imaging protocol for patients with recurrent shoulder stabilization and limit the number of shoulder CT scans. LEVEL OF EVIDENCE: Level III, retrospective therapeutic trial.


Assuntos
Reabsorção Óssea/diagnóstico por imagem , Instabilidade Articular/diagnóstico por imagem , Articulação do Ombro/diagnóstico por imagem , Adulto , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Lesões do Ombro , Software , Tomografia Computadorizada por Raios X/métodos
17.
PLoS Med ; 14(4): e1002287, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28441426

RESUMO

INTRODUCTION: The molecular underpinnings of the dissociation of cognitive performance and neuropathological burden are poorly understood, and there are currently no known genetic or epigenetic determinants of the dissociation. METHODS AND FINDINGS: "Residual cognition" was quantified by regressing out the effects of cerebral pathologies and demographic characteristics on global cognitive performance proximate to death. To identify genes influencing residual cognition, we leveraged neuropathological, genetic, epigenetic, and transcriptional data available for deceased participants of the Religious Orders Study (n = 492) and the Rush Memory and Aging Project (n = 487). Given that our sample size was underpowered to detect genome-wide significance, we applied a multistep approach to identify genes influencing residual cognition, based on our prior observation that independent genetic and epigenetic risk factors can converge on the same locus. In the first step (n = 979), we performed a genome-wide association study with a predefined suggestive p < 10-5, and nine independent loci met this threshold in eight distinct chromosomal regions. Three of the six genes within 100 kb of the lead SNP are expressed in the dorsolateral prefrontal cortex (DLPFC): UNC5C, ENC1, and TMEM106B. In the second step, in the subset of participants with DLPFC DNA methylation data (n = 648), we found that residual cognition was related to differential DNA methylation of UNC5C and ENC1 (false discovery rate < 0.05). In the third step, in the subset of participants with DLPFC RNA sequencing data (n = 469), brain transcription levels of UNC5C and ENC1 were evaluated for their association with residual cognition: RNA levels of both UNC5C (estimated effect = -0.40, 95% CI -0.69 to -0.10, p = 0.0089) and ENC1 (estimated effect = 0.0064, 95% CI 0.0033 to 0.0096, p = 5.7 × 10-5) were associated with residual cognition. In secondary analyses, we explored the mechanism of these associations and found that ENC1 may be related to the previously documented effect of depression on cognitive decline, while UNC5C may alter the composition of presynaptic terminals. Of note, the TMEM106B allele identified in the first step as being associated with better residual cognition is in strong linkage disequilibrium with rs1990622A (r2 = 0.66), a previously identified protective allele for TDP-43 proteinopathy. Limitations include the small sample size for the genetic analysis, which was underpowered to detect genome-wide significance, the evaluation being limited to a single cortical region for epigenetic and transcriptomic data, and the use of categorical measures for certain non-amyloid-plaque, non-neurofibrillary-tangle neuropathologies. CONCLUSIONS: Through a multistep analysis of cognitive, neuropathological, genomic, epigenomic, and transcriptomic data, we identified ENC1 and UNC5C as genes with convergent genetic, epigenetic, and transcriptomic evidence supporting a potential role in the dissociation of cognition and neuropathology in an aging population, and we expanded our understanding of the TMEM106B haplotype that is protective against TDP-43 proteinopathy.


Assuntos
Envelhecimento/fisiologia , Encéfalo/patologia , Transtornos Cognitivos/genética , Cognição/fisiologia , Proteínas de Membrana/genética , Proteínas dos Microfilamentos/genética , Proteínas do Tecido Nervoso/genética , Neuropeptídeos/genética , Proteínas Nucleares/genética , Receptores de Superfície Celular/genética , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Alelos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Transtornos Cognitivos/metabolismo , Metilação de DNA , Depressão/metabolismo , Epigênese Genética , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , Proteínas de Membrana/metabolismo , Memória , Proteínas dos Microfilamentos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores de Netrina , Neuropeptídeos/metabolismo , Proteínas Nucleares/metabolismo , Polimorfismo de Nucleotídeo Único , RNA/metabolismo , Receptores de Superfície Celular/metabolismo , Proteinopatias TDP-43/genética
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