Masitinib for mild-to-moderate Alzheimer's disease: results from a randomized, placebo-controlled, phase 3, clinical trial.

BACKGROUND: Masitinib is an orally administered tyrosine kinase inhibitor that targets activated cells of the neuroimmune system (mast cells and microglia). Study AB09004 evaluated masitinib as an adjunct to cholinesterase inhibitor and/or memantine in patients with mild-to-moderate dementia due to probable Alzheimer's disease (AD). METHODS: Study AB09004 was a randomized, double-blind, two parallel-group (four-arm), placebo-controlled trial. Patients aged ≥50 years, with clinical diagnosis of mild-to-moderate probable AD and a Mini-Mental State Examination (MMSE) score of 12-25 were randomized (1:1) to receive masitinib 4.5 mg/kg/day (administered orally as two intakes) or placebo. A second, independent parallel group (distinct for statistical analysis and control arm), randomized patients (2:1) to masitinib at an initial dose of 4.5 mg/kg/day for 12 weeks that was then titrated to 6.0 mg/kg/day, or equivalent placebo. Multiple primary outcomes (each tested at a significance level of 2.5%) were least-squares mean change from baseline to week 24 in the Alzheimer's Disease Assessment Scale - cognitive subscale (ADAS-cog), or the Alzheimer's Disease Cooperative Study Activities of Daily Living Inventory scale (ADCS-ADL). Safety for each masitinib dose level was compared against a pooled placebo population. RESULTS: Masitinib (4.5 mg/kg/day) (n=182) showed significant benefit over placebo (n=176) according to the primary endpoint of ADAS-cog, -1.46 (95% CI [-2.46, -0.45]) (representing an overall improvement in cognition) versus 0.69 (95% CI [-0.36, 1.75]) (representing increased cognitive deterioration), respectively, with a significant between-group difference of -2.15 (97.5% CI [-3.48, -0.81]); p<0.001. For the ADCS-ADL primary endpoint, the between-group difference was 1.82 (97.5% CI [-0.15, 3.79]); p=0.038 (i.e., 1.01 (95% CI [-0.48, 2.50]) (representing an overall functional improvement) versus -0.81 (95% CI [-2.36, 0.74]) (representing increased functional deterioration), respectively). Safety was consistent with masitinib's known profile (maculo-papular rash, neutropenia, hypoalbuminemia). Efficacy results from the independent parallel group of titrated masitinib 6.0 mg/kg/day versus placebo (n=186 and 91 patients, respectively) were inconclusive and no new safety signal was observed. CONCLUSIONS: Masitinib (4.5 mg/kg/day) may benefit people with mild-to-moderate AD. A confirmatory study has been initiated to substantiate these data. TRIAL REGISTRATION: EudraCT: 2010-021218-50. CLINICALTRIALS: gov : NCT01872598.

The health status: the ignored risk factor in dementia incidence. NEDICES cohort.

BACKGROUND: The causes of the dementia decrease in affluent countries are not well known but health amelioration could probably play a major role. Nevertheless, although many vascular and systemic disorders in adult life are well-known risk factors (RF) for dementia and Alzheimer disease (AD), health status is rarely considered as a single RF. AIM: To analyse whether the health status and the self-perceived health (SPH) could be RF for dementia and AD and to discuss its biological basis. METHODS: We analysed different objective health measures and SPH as RF for dementia and AD incidence in 4569 participants of the NEDICES cohort by means of Cox-regression models. The mean follow-up period was 3.2 (range: 0.03-6.6) years. RESULTS: Ageing, low education, history of stroke, and "poor" SPH were the main RF for dementia and AD incidence, whereas physical activity was protective. "Poor" SPH had a hazard ratio = 1.66 (95% CI 1.17-2.46; p = 0.012) after controlling for different confounders. DISCUSSION: According to data from NEDICES cohort, SPH is a better predictor of dementia and AD than other more objective health status proxies. SPH should be considered a holistic and biologically rooted indicator of health status, which can predict future development of dementia and AD in older adults. CONCLUSIONS: Our data indicate that it is worthwhile to include the SPH status as a RF in the studies of dementia and AD incidence and to explore the effect of its improvement in the evolution of this incidence.

Is milk and dairy intake a preventive factor for elderly cognition (dementia and Alzheimer's)? A quality review of cohort surveys.

Milk and dairy (M&D) is a longstanding human food with widespread use. Many studies showed the preventive capacity of M&D in several human health disorders, but its utility in others is under discussion. Aging has been associated to elderly cognitive decline including dementia-Alzheimer syndrome (Dem-AD). The absence of a therapy to impede or postpone Dem-AD determines the need for its prevention, including nutritional factors. To evaluate the preventive capacity of M&D consumption in elderly Dem-AD we performed a systematic review in the main biomedical databases and information resources, but we present this study as a narrative review to discuss better the complexity of this subject. The elderly Dem-AD has a long pre-symptomatic period and the M&D intake has a widespread use. These determinants and the quality flaws of published studies impeach us to answer whether M&D consumption is preventive for Dem-AD. Moreover, two long Japanese cohorts suggest that M&D intake could prevent Dem-AD. Prospective cohorts beginning in midlife (or early life) could answer this question in the future.

Impacto de la hospitalización en pacientes centenarios ingresados por enfermedad aguda. Descripción de una serie de 165 casos y comparación con la literatura / Impact of hospital admission on centenarians admitted due to an acute illness. A description of a series of 165 cases and comparison with the literature

Introducción: El envejecimiento de la población está suponiendo un aumento de pacientes centenarios, cuyas características podrían diferenciarse de las de los pacientes de menor edad. Este estudio se realizó para conocer el impacto de la hospitalización en los pacientes de 100 o más años ingresados por enfermedad aguda. Material y métodos: Se realizó un estudio observacional retrospectivo que incluyó a los pacientes con edad ≥ 100 años atendidos por el Servicio de Geriatría (SG) de un hospital universitario de tercer nivel desde 1995 hasta 2016. Se consultaron las bases de datos clínico-administrativas del SG, que incluían datos demográficos, clínicos, funcionales, cognitivos y administrativos. Se incluyó a pacientes atendidos en la Unidad Geriátrica de Agudos (UGA), en la Unidad de Ortogeriatría y como Interconsultas. Resultados: Se estudió a 165 pacientes, de 101,6 +/- 1,7 años de edad media +/- desviación estándar (rango 100-109), de los que 140 (85%) fueron mujeres. La estancia media fue de 10,3 +/- 7,4 días. El motivo de ingreso más frecuente en la UGA fueron las infecciones respiratorias (41%). La mortalidad global fue del 16%, pero en la UGA aumentó al 31%. La incapacidad funcional moderada-grave aumentó del 51% basal al 96% al alta y la incapacidad para la deambulación aumentó del 52% basal al 99% al alta. El porcentaje de pacientes residentes en domicilio disminuyó del 71 al 29% al alta. Conclusiones: En los pacientes centenarios, la hospitalización provoca una tasa elevada de mortalidad, un deterioro importante en su situación funcional y una reducción de la probabilidad de volver a su domicilio previo

Introduction: The number of centenarians is increasing with the aging of the Spanish population. This age group might present different clinical features from younger groups. This study was carried out to determine the impact hospital admission on centenarians with an acute disease. Materials and methods: A retrospective observational study was conducted that included patients ≥100 years-old admitted from 1995 to 2016 to a third level university hospital and attended by the Geriatrics department in the acute ward, the Orthogeriatric ward, and by request. An analysis was made using the clinical-administrative databases containing information about the demographics, clinical, functional and cognitive features, length of hospital length, as well as discharge destination. Results: The study included 165 patients with a mean age of 101.6 +/- 1.7 (range 100-109) years, of whom 140 (85%) were female. The mean hospital stay was 10.3 +/- 7.4 days. Respiratory infections (41%) were the most common cause of admission to the Acute Geriatric Unit (AGU). The overall in-hospital mortality was 16%, but mortality in AGU reached up to 31%. There was an increase on moderate-severe functional disability (51% to 96%), and on the inability to walk independently (52% to 99%) from baseline to admission. There was a reduction in people living in their own home from 71% prior to admission to 29% at hospital discharge. Conclusions: Centenarians who required hospital admission showed a high rate of mortality, a significant deterioration in their functional capacity, and a decrease in their chances of going back to their own home at discharge

[Impact of hospital admission on centenarians admitted due to an acute illness. A description of a series of 165 cases and comparison with the literature]. / Impacto de la hospitalización en pacientes centenarios ingresados por enfermedad aguda. Descripción de una serie de 165 casos y comparación con la literatura.

INTRODUCTION: The number of centenarians is increasing with the aging of the Spanish population. This age group might present different clinical features from younger groups. This study was carried out to determine the impact hospital admission on centenarians with an acute disease. MATERIALS AND METHODS: A retrospective observational study was conducted that included patients ≥100 years-old admitted from 1995 to 2016 to a third level university hospital and attended by the Geriatrics department in the acute ward, the Orthogeriatric ward, and by request. An analysis was made using the clinical-administrative databases containing information about the demographics, clinical, functional and cognitive features, length of hospital length, as well as discharge destination. RESULTS: The study included 165 patients with a mean age of 101.6 ± 1.7 (range 100-109) years, of whom 140 (85%) were female. The mean hospital stay was 10.3 ± 7.4 days. Respiratory infections (41%) were the most common cause of admission to the Acute Geriatric Unit (AGU). The overall in-hospital mortality was 16%, but mortality in AGU reached up to 31%. There was an increase on moderate-severe functional disability (51% to 96%), and on the inability to walk independently (52% to 99%) from baseline to admission. There was a reduction in people living in their own home from 71% prior to admission to 29% at hospital discharge. CONCLUSIONS: Centenarians who required hospital admission showed a high rate of mortality, a significant deterioration in their functional capacity, and a decrease in their chances of going back to their own home at discharge.

Evaluation of Candidate Genes Related to Neuronal Apoptosis in Late-Onset Alzheimer's Disease.

The objective of this study was to identify genetic variation in genes encoding death receptors and signals that modulate their activity. After conducting a meta-analysis with five previous genome-wide association studies and aggregated data, the most significant signals, (TNF locus: rs2395488, rs2534672, and rs9267445; and FASLG locus: rs730278), were replicated in 1,046 cases and 372 controls. The rs2395488 and rs2534672 markers showed a modest protective effect (OR = 0.849, p = 0.49780;OR= 0.687, p = 0.11335), in contrast to rs730278 marker (OR = 1.146, p = 0.17212), which did not follow the previous effect direction; in any case it reached the significance level. Final meta-analysis, adding the replication sample, confirmed these observations. We concluded that FASLG marker is not etiologically linked to Alzheimer's disease. However, single nucleotide polymorphisms around TNF locus require further analyses in order to explain the association between Alzheimer's disease and human leukocyte antigen.

Assessing the role of the TREM2 p.R47H variant as a risk factor for Alzheimer's disease and frontotemporal dementia.

A non-synonymous genetic rare variant, rs75932628-T (p.R47H), in the TREM2 gene has recently been reported to be a strong genetic risk factor for Alzheimer's disease (AD). Also, rare recessive mutations have been associated with frontotemporal dementia (FTD). We aimed to investigate the role of p.R47H variant in AD and FTD through a multi-center study comprising 3172 AD and 682 FTD patients and 2169 healthy controls from Spain. We found that 0.6% of AD patients carried this variant compared to 0.1% of controls (odds ratio [OR] = 4.12, 95% confidence interval [CI] = 1.21-14.00, p = 0.014). A meta-analysis comprising 32,598 subjects from 4 previous studies demonstrated the large effect of the p.R47H variant in AD risk (OR = 4.11, 95% CI = 2.99-5.68, p = 5.27×10(-18)). We did not find an association between p.R47H and age of onset of AD or family history of dementia. Finally, none of the FTD patients harbored this genetic variant. These data strongly support the important role of p.R47H in AD risk, and suggest that this rare genetic variant is not related to FTD.

Genetic study of neurexin and neuroligin genes in Alzheimer's disease.

The interaction between neurexins and neuroligins promotes the formation of functional synaptic structures. Recently, it has been reported that neurexins and neuroligins are proteolytically processed by presenilins at synapses. Based on this interaction and the role of presenilins in familial Alzheimer's disease (AD), we hypothesized that dysfunction of the neuroligin-neurexin pathway might be associated with AD. To explore this hypothesis, we carried out a meta-analysis of five genome-wide association studies (GWAS) comprising 1, 256 SNPs in the NRXN1, NRXN2, NRXN3, and NLGN1 genes (3,009 cases and 3,006 control individuals). We identified a marker in the NRXN3 gene (rs17757879) that showed a consistent protective effect in all GWAS, however, the statistical significance obtained did not resist multiple testing corrections (OR = 0.851, p = 0.002). Nonetheless, gender analysis revealed that this effect was restricted to males. A combined meta-analysis of the former five GWAS together with a replication Spanish sample consisting of 1,785 cases and 1,634 controls confirmed this observation (rs17757879, OR = 0.742, 95% CI = 0.632-0.872, p = 0.00028, final meta-analysis). We conclude that NRXN3 might have a role in susceptibility to AD in males.

Síndrome mielodisplásico en el paciente mayor: valoración geriátrica integral y recomendaciones terapéuticas / Myelodysplastic syndrome in the elderly: comprehensive geriatric assessment and therapeutic recommendations

La edad de presentación de los síndromes mielodisplásicos (SMD) suele ser alrededor de los 70 años. A pesar de esto, la mayor parte de los ensayos clínicos se restringen a sujetos más jóvenes, con lo cual el tratamiento de los pacientes mayores con SMD no siempre es el mejor. El paciente mayor presenta características fisiológicas que lo diferencian del adulto, y esto condiciona el tratamiento farmacológico. En este sentido, la valoración geriátrica integral (VGI) cobra especial importancia. Este artículo recoge las conclusiones de la I Reunión de Especialistas de la Sociedad Española de Medicina Geriátrica y de la Sociedad Española de Hematología y Hemoterapia, y propone la implantación de instrumentos de la VGI que ayuden en el proceso de toma de decisiones del paciente mayor con SMD. Los resultados se centrarán en el diagnóstico, pronóstico, tratamiento y manejo de los efectos adversos en este grupo de pacientes (AU)

The onset of myelodysplastic syndromes (MDS) is usually around the age of 70. Despite this, most clinical trials are restricted to younger subjects. Thus, the management of elderly patients with MDS is not always optimal. Physiologically, elderly patients show characteristics that differ from those of younger patients and that condition their pharmacological treatment. In this regard, the comprehensive geriatric assessment (CGA) becomes particularly important. This document gathers conclusions from the 1st Meeting of Members of the Sociedad Española de Medicina Geriátrica and the Sociedad Española de Hematología y Hemoterapia, with the objective of proposing the establishment of CGA instruments to assist in the decision-making process of elderly patients with MDS. The results of this consensus document will focus on the diagnosis, prognosis, treatment and management of adverse events in this age group (AU)

Estrogen receptor alpha gene variants are associated with Alzheimer's disease.

The present research is aimed at assessing the role of 3 estrogen receptor alpha (ESR1) gene variants in late onset Alzheimer's disease (AD) susceptibility. One thousand one hundred thirteen unrelated late onset sporadic AD patients, 1109 healthy controls and 121 neurologically healthy elderly controls were used to carry out case-control genetic association studies with ESR1 rs3844508, rs2234693, and ESR1 noncoding deletion 1 (ESR1-NCD1) polymorphisms. Thirty-five healthy male samples were used for molecular analyses. The rs2234693 polymorphism is associated with AD in our population (odds ratio [OR], 1.29; p = 0.008). The rs3844508 marker confers protection against AD in males (OR, 0.57; p = 0.001) and the deletion ESR1-NCD1 is a risk factor for AD in women (OR, 1.67; p < 0.001). Molecular analyses on ESR1-NCD1 indicate that this deletion confers a higher response to estradiol activity on ESR1 receptor and it is also associated with differential expression of ESR1 isoforms. Our results support the involvement of ESR1 gene in AD and point to the existence of sexual dimorphism for ESR1 markers. In addition, carriers of ESR1-NCD1 deletion could overrespond to estradiol action.

[Myelodysplastic syndrome in the elderly: comprehensive geriatric assessment and therapeutic recommendations]. / Síndrome mielodisplásico en el paciente mayor: valoración geriátrica integral y recomendaciones terapéuticas.

The onset of myelodysplastic syndromes (MDS) is usually around the age of 70. Despite this, most clinical trials are restricted to younger subjects. Thus, the management of elderly patients with MDS is not always optimal. Physiologically, elderly patients show characteristics that differ from those of younger patients and that condition their pharmacological treatment. In this regard, the comprehensive geriatric assessment (CGA) becomes particularly important. This document gathers conclusions from the 1(st) Meeting of Members of the Sociedad Española de Medicina Geriátrica and the Sociedad Española de Hematología y Hemoterapia, with the objective of proposing the establishment of CGA instruments to assist in the decision-making process of elderly patients with MDS. The results of this consensus document will focus on the diagnosis, prognosis, treatment and management of adverse events in this age group.

Eficiencia de las unidades geriátricas de agudos: metaanálisis de estudios controlados / Efficiency of acute geriatric units: a meta-analysis of controlled studies

Objetivo. Tras objetivar la eficacia en la reducción de la incidencia de deterioro funcional y mayor probabilidad de volver al domicilio previo entre los pacientes ancianos hospitalizados por patología médica aguda atendidos en unidades geriátricas de agudos (UGA) frente a las unidades de cuidados convencionales nos proponemos evaluar la eficiencia de dicha atención. Material y métodos. Revisión sistemática y metaanálisis de estudios controlados (aleatorizados, no aleatorizados y casos-control) que compararon la atención en UGA con la atención en unidades convencionales de hospitalización en pacientes de 65 y más años con patología médica aguda. Se excluyeron estudios sobre bases de datos administrativas, los que evaluaban la atención sobre una sola patología y los que valoraban unidades con cuidados en fase aguda y subaguda. Se realizó una revisión bibliográfica de artículos publicados hasta el 31 de agosto de 2008 en Medline, Embase, Biblioteca Cochrane y listado de referencias de revisiones sistemáticas y artículos revisados. La selección de los estudios y extracción de datos sobre estancia y costes de atención hospitalaria se realizó por dos investigadores de forma independiente. Resultados. Se incluyeron 11 estudios, de los que 5 fueron aleatorizados, 4 no aleatorizados y 2 estudios caso-control disponiendo de datos de estancia para todos ellos y de costes hospitalarios en 7 (4 ensayos clínicos, 2 estudios no aleatorizados y 1 caso-control). El análisis global de todos los estudios mostró que, en comparación con los ancianos hospitalizados en unidades convencionales, los que lo hicieron en las UGA tuvieron una reducción estadísticamente significativa de la estancia hospitalaria (diferencia de medias de – 1,01 días; IC del 95%, –1,66 a –0,36) y de los costes hospitalarios de atención (diferencia de medias de –330 dólares; IC del 95%, –540 a –120). Conclusiones. La atención en UGA es más eficiente que la proporcionada en unidades convencionales ya que, además de conseguir una reducción de la incidencia de deterioro funcional al alta y aumentar la probabilidad de volver al domicilio previo, lo hacen con una reducción de la estancia media hospitalaria y los costes hospitalarios de la atención(AU)

Objective. After analysing the effectiveness in the reduction in the incidence of functional impairment and a higher probability of returning home between elderly patients hospitalised due to an acute medical illness cared for in acute geriatric units (AGU) compared to conventional care units, we propose to assess the efficiency of this care. Material and methods. A systematic review and meta-analysis was made of controlled studies (randomised, no randomised and case-control) that compared care in UGA with care in conventional hospital units of patients of 65years and over with an acute medical illness. Studies on administrative data bases, those that evaluated care of a single disease, and those that assessed units with care in the acute and sub-acute phase were excluded. A literature review was performed on articles published up to 31st of August 2008 in Medline, Embase, Cochrane Library, and references of systematic reviews and reviewed articles. The selection of the studies and the extraction of data on the hospital stay and care costs was made independently by two different researchers. Results. A total of 11 studies were included, of which 5 were randomised, 4 were non-randomised, and 2 case control, all of them providing data on hospital stay, with 7 of them providing data on hospital costs (4 clinical trials, 2 non-randomised and 1 case-control). The overall analysis of all the studies showed that those admitted to UGA had a statistically significant reduction in hospital length of stay compared to the elderly hospitalised in conventional units (mean difference –1.01days; 95% CI, –1.66 to –0.36) and hospital care costs (mean difference of –330 US dollars; 95% CI, –540 to –120). Conclusions. Care in AGU is more efficient than that provided in conventional units, since, as well as achieving a reduction in the incidence of functional impairment at discharge and increasing the probability of returning home, they reduce mean hospital stay and the hospital care costs(AU)

[Efficiency of acute geriatric units: a meta-analysis of controlled studies]. / Eficiencia de las unidades geriátricas de agudos: metaanálisis de estudios controlados.

OBJECTIVE: After analysing the effectiveness in the reduction in the incidence of functional impairment and a higher probability of returning home between elderly patients hospitalised due to an acute medical illness cared for in acute geriatric units (AGU) compared to conventional care units, we propose to assess the efficiency of this care. MATERIAL AND METHODS: A systematic review and meta-analysis was made of controlled studies (randomised, no randomised and case-control) that compared care in UGA with care in conventional hospital units of patients of 65 years and over with an acute medical illness. Studies on administrative data bases, those that evaluated care of a single disease, and those that assessed units with care in the acute and sub-acute phase were excluded. A literature review was performed on articles published up to 31st of August 2008 in Medline, Embase, Cochrane Library, and references of systematic reviews and reviewed articles. The selection of the studies and the extraction of data on the hospital stay and care costs was made independently by two different researchers. RESULTS: A total of 11 studies were included, of which 5 were randomised, 4 were non-randomised, and 2 case control, all of them providing data on hospital stay, with 7 of them providing data on hospital costs (4 clinical trials, 2 non-randomised and 1 case-control). The overall analysis of all the studies showed that those admitted to UGA had a statistically significant reduction in hospital length of stay compared to the elderly hospitalised in conventional units (mean difference -1.01 days; 95% CI, -1.66 to -0.36) and hospital care costs (mean difference of -330 US dollars; 95% CI, -540 to -120). CONCLUSIONS: Care in AGU is more efficient than that provided in conventional units, since, as well as achieving a reduction in the incidence of functional impairment at discharge and increasing the probability of returning home, they reduce mean hospital stay and the hospital care costs.

Genetic association of complement receptor 1 polymorphism rs3818361 in Alzheimer's disease.

Complement receptor 1 gene polymorphism rs3818361 was recently shown to increase the risk of Alzheimer's disease (AD). We performed an independent replication study of this genetic variant in 2,470 individuals from Spain. By applying an allelic model, we observed a trend toward an association between this marker and late-onset AD susceptibility in our case-control study (odds ratio = 1.114, 95% confidence interval: 0.958-1.296, P = .16). Meta-analysis of available studies (n = 31,771 individuals), including previous studies and public genome-wide association study resources (Alzheimer's Disease Neuroimaging Initiative, Translational Genomics Research Institute, and Multi-site Collaborative Study for Genotype-Phenotype Associations in Alzheimer's Disease), strongly supports the effect of rs3818361 (odds ratio = 1.180, 95% confidence interval: 1.113-1.252, P < 2.99E-8) and suggests the existence of between-study heterogeneity (P < .05). We concluded that the complement receptor 1 gene may contribute to AD risk, although its effect size could be smaller than previously estimated.

The membrane-spanning 4-domains, subfamily A (MS4A) gene cluster contains a common variant associated with Alzheimer's disease.

BACKGROUND: In order to identify novel loci associated with Alzheimer's disease (AD), we conducted a genome-wide association study (GWAS) in the Spanish population. METHODS: We genotyped 1,128 individuals using the Affymetrix Nsp I 250K chip. A sample of 327 sporadic AD patients and 801 controls with unknown cognitive status from the Spanish general population were included in our initial study. To increase the power of the study, we combined our results with those of four other public GWAS datasets by applying identical quality control filters and the same imputation methods, which were then analyzed with a global meta-GWAS. A replication sample with 2,200 sporadic AD patients and 2,301 controls was genotyped to confirm our GWAS findings. RESULTS: Meta-analysis of our data and independent replication datasets allowed us to confirm a novel genome-wide significant association of AD with the membrane-spanning 4-domains subfamily A (MS4A) gene cluster (rs1562990, P = 4.40E-11, odds ratio = 0.88, 95% confidence interval 0.85 to 0.91, n = 10,181 cases and 14,341 controls). CONCLUSIONS: Our results underscore the importance of international efforts combining GWAS datasets to isolate genetic loci for complex diseases.

The MTHFD1L gene rs11754661 marker is not associated with Alzheimer's disease in a sample of the Spanish population.

The MTHFD1L gene SNP variant rs11754661 was found to increase the risk of Alzheimer's disease in a recent Whole Genome Association Study. We have carried out an independent study of this genetic variant in 2467 individuals from Spain. We found no evidence of association between the MTHFD1L marker and susceptibility to Alzheimer's disease in our sample.

The CALHM1 P86L polymorphism is a genetic modifier of age at onset in Alzheimer's disease: a meta-analysis study.

The only established genetic determinant of non-Mendelian forms of Alzheimer's disease (AD) is the ε4 allele of the apolipoprotein E gene (APOE). Recently, it has been reported that the P86L polymorphism of the calcium homeostasis modulator 1 gene (CALHM1) is associated with the risk of developing AD. In order to independently assess this association, we performed a meta-analysis of 7,873 AD cases and 13,274 controls of Caucasian origin (from a total of 24 centers in Belgium, Finland, France, Italy, Spain, Sweden, the UK, and the USA). Our results indicate that the CALHM1 P86L polymorphism is likely not a genetic determinant of AD but may modulate age of onset by interacting with the effect of the ε4 allele of the APOE gene.

Genome-wide analysis of genetic loci associated with Alzheimer disease.

CONTEXT: Genome-wide association studies (GWAS) have recently identified CLU, PICALM, and CR1 as novel genes for late-onset Alzheimer disease (AD). OBJECTIVES: To identify and strengthen additional loci associated with AD and confirm these in an independent sample and to examine the contribution of recently identified genes to AD risk prediction in a 3-stage analysis of new and previously published GWAS on more than 35,000 persons (8371 AD cases). DESIGN, SETTING, AND PARTICIPANTS: In stage 1, we identified strong genetic associations (P < 10(-3)) in a sample of 3006 AD cases and 14,642 controls by combining new data from the population-based Cohorts for Heart and Aging Research in Genomic Epidemiology consortium (1367 AD cases [973 incident]) with previously reported results from the Translational Genomics Research Institute and the Mayo AD GWAS. We identified 2708 single-nucleotide polymorphisms (SNPs) with P < 10(-3). In stage 2, we pooled results for these SNPs with the European AD Initiative (2032 cases and 5328 controls) to identify 38 SNPs (10 loci) with P < 10(-5). In stage 3, we combined data for these 10 loci with data from the Genetic and Environmental Risk in AD consortium (3333 cases and 6995 controls) to identify 4 SNPs with P < 1.7x10(-8). These 4 SNPs were replicated in an independent Spanish sample (1140 AD cases and 1209 controls). Genome-wide association analyses were completed in 2007-2008 and the meta-analyses and replication in 2009. MAIN OUTCOME MEASURE: Presence of Alzheimer disease. RESULTS: Two loci were identified to have genome-wide significance for the first time: rs744373 near BIN1 (odds ratio [OR],1.13; 95% confidence interval [CI],1.06-1.21 per copy of the minor allele; P = 1.59x10(-11)) and rs597668 near EXOC3L2/BLOC1S3/MARK4 (OR, 1.18; 95% CI, 1.07-1.29; P = 6.45x10(-9)). Associations of these 2 loci plus the previously identified loci CLU and PICALM with AD were confirmed in the Spanish sample (P < .05). However, although CLU and PICALM were confirmed to be associated with AD in this independent sample, they did not improve the ability of a model that included age, sex, and APOE to predict incident AD (improvement in area under the receiver operating characteristic curve from 0.847 to 0.849 in the Rotterdam Study and 0.702 to 0.705 in the Cardiovascular Health Study). CONCLUSIONS: Two genetic loci for AD were found for the first time to reach genome-wide statistical significance. These findings were replicated in an independent population. Two recently reported associations were also confirmed. These loci did not improve AD risk prediction. While not clinically useful, they may implicate biological pathways useful for future research.

CALHM1 P86L polymorphism is associated with late-onset Alzheimer's disease in a recessive model.

CALHM1 gene coding non-synonymous SNP P86L (rs2986017) was reported to increase the risk of Alzheimer's disease (AD) in a recent study. We have investigated this genetic variant in 2470 individuals from Spain to conduct an independent replication study of the proposed SNP marker. By applying a recessive model, we observed weak evidence of an association between P86L mutation and late-onset AD (LOAD) susceptibility in our case-control study (OR =1.38 C.I. = [1.01-1.89]). Meta-analysis of available studies also supports a recessive model for CALHM1 P86L variant and provides evidence of between study heterogeneity. Importantly, we found that adjusted mean age at AD onset in P86L homozygous LOAD patients was significantly earlier that in the rest of patients (77.01 +/- 6.1 for P86L homozygous carriers versus 79.0 +/- 6.0 for the rest of patients, p=0.002). We concluded that the CALMH1 gene may contribute to AD risk in our study population. The observed genetic model (recessive) and the estimated magnitude of the effect both imply that virtually all studies performed to date were markedly underpowered to detect this effect and underscore the importance of follow up, replication, and meta-analyses of promising genetic signals.