Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
Am J Epidemiol ; 185(12): 1317-1326, 2017 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-28459963

RESUMEN

We studied the associations of leukocyte telomere length (LTL) with all-cause, cardiovascular disease, and cancer mortality in 12,199 adults participating in 2 population-based prospective cohort studies from Europe (ESTHER) and the United States (Nurses' Health Study). Blood samples were collected in 1989-1990 (Nurses' Health Study) and 2000-2002 (ESTHER). LTL was measured by quantitative polymerase chain reaction. We calculated z scores for LTL to standardize LTL measurements across the cohorts. Cox proportional hazards regression models were used to calculate relative mortality according to continuous levels and quintiles of LTL z scores. The hazard ratios obtained from each cohort were subsequently pooled by meta-analysis. Overall, 2,882 deaths were recorded during follow-up (Nurses' Health Study, 1989-2010; ESTHER, 2000-2015). LTL was inversely associated with age in both cohorts. After adjustment for age, a significant inverse trend of LTL with all-cause mortality was observed in both cohorts. In random-effects meta-analysis, age-adjusted hazard ratios for the shortest LTL quintile compared with the longest were 1.23 (95% confidence interval (CI): 1.04, 1.46) for all-cause mortality, 1.29 (95% CI: 0.83, 2.00) for cardiovascular mortality, and 1.10 (95% CI: 0.88, 1.37) for cancer mortality. In this study population with an age range of 43-75 years, we corroborated previous evidence suggesting that LTL predicts all-cause mortality beyond its association with age.


Asunto(s)
Enfermedades Cardiovasculares/mortalidad , Leucocitos/ultraestructura , Neoplasias/mortalidad , Telómero/ultraestructura , Adulto , Factores de Edad , Anciano , Causas de Muerte , Europa (Continente) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Estados Unidos
2.
Hum Mol Genet ; 25(17): 3863-3876, 2016 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-27402876

RESUMEN

Breast cancer is the most diagnosed malignancy and the second leading cause of cancer mortality in females. Previous association studies have identified variants on 2q35 associated with the risk of breast cancer. To identify functional susceptibility loci for breast cancer, we interrogated the 2q35 gene desert for chromatin architecture and functional variation correlated with gene expression. We report a novel intergenic breast cancer risk locus containing an enhancer copy number variation (enCNV; deletion) located approximately 400Kb upstream to IGFBP5, which overlaps an intergenic ERα-bound enhancer that loops to the IGFBP5 promoter. The enCNV is correlated with modified ERα binding and monoallelic-repression of IGFBP5 following oestrogen treatment. We investigated the association of enCNV genotype with breast cancer in 1,182 cases and 1,362 controls, and replicate our findings in an independent set of 62,533 cases and 60,966 controls from 41 case control studies and 11 GWAS. We report a dose-dependent inverse association of 2q35 enCNV genotype (percopy OR = 0.68 95%CI 0.55-0.83, P = 0.0002; replication OR = 0.77 95% CI 0.73-0.82, P = 2.1 × 10-19) and identify 13 additional linked variants (r2 > 0.8) in the 20Kb linkage block containing the enCNV (P = 3.2 × 10-15 - 5.6 × 10-17). These associations were independent of previously reported 2q35 variants, rs13387042/rs4442975 and rs16857609, and were stronger for ER-positive than ER-negative disease. Together, these results suggest that 2q35 breast cancer risk loci may be mediating their effect through IGFBP5.


Asunto(s)
Neoplasias de la Mama/genética , Proteínas Portadoras/genética , Cromosomas Humanos Par 2/genética , Elementos de Facilitación Genéticos , Proteína 5 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Eliminación de Secuencia , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , Humanos , Células MCF-7 , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , Adulto Joven
3.
Nat Commun ; 7: 10023, 2016 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-26831199

RESUMEN

Reduced glomerular filtration rate defines chronic kidney disease and is associated with cardiovascular and all-cause mortality. We conducted a meta-analysis of genome-wide association studies for estimated glomerular filtration rate (eGFR), combining data across 133,413 individuals with replication in up to 42,166 individuals. We identify 24 new and confirm 29 previously identified loci. Of these 53 loci, 19 associate with eGFR among individuals with diabetes. Using bioinformatics, we show that identified genes at eGFR loci are enriched for expression in kidney tissues and in pathways relevant for kidney development and transmembrane transporter activity, kidney structure, and regulation of glucose metabolism. Chromatin state mapping and DNase I hypersensitivity analyses across adult tissues demonstrate preferential mapping of associated variants to regulatory regions in kidney but not extra-renal tissues. These findings suggest that genetic determinants of eGFR are mediated largely through direct effects within the kidney and highlight important cell types and biological pathways.


Asunto(s)
Predisposición Genética a la Enfermedad , Insuficiencia Renal Crónica/genética , Regulación de la Expresión Génica , Estudio de Asociación del Genoma Completo , Genotipo , Humanos
4.
Diabetes ; 65(3): 803-17, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26631737

RESUMEN

Elevated concentrations of albumin in the urine, albuminuria, are a hallmark of diabetic kidney disease and are associated with an increased risk for end-stage renal disease and cardiovascular events. To gain insight into the pathophysiological mechanisms underlying albuminuria, we conducted meta-analyses of genome-wide association studies and independent replication in up to 5,825 individuals of European ancestry with diabetes and up to 46,061 without diabetes, followed by functional studies. Known associations of variants in CUBN, encoding cubilin, with the urinary albumin-to-creatinine ratio (UACR) were confirmed in the overall sample (P = 2.4 × 10(-10)). Gene-by-diabetes interactions were detected and confirmed for variants in HS6ST1 and near RAB38/CTSC. Single nucleotide polymorphisms at these loci demonstrated a genetic effect on UACR in individuals with but not without diabetes. The change in the average UACR per minor allele was 21% for HS6ST1 (P = 6.3 × 10(-7)) and 13% for RAB38/CTSC (P = 5.8 × 10(-7)). Experiments using streptozotocin-induced diabetic Rab38 knockout and control rats showed higher urinary albumin concentrations and reduced amounts of megalin and cubilin at the proximal tubule cell surface in Rab38 knockout versus control rats. Relative expression of RAB38 was higher in tubuli of patients with diabetic kidney disease compared with control subjects. The loci identified here confirm known pathways and highlight novel pathways influencing albuminuria.


Asunto(s)
Albuminuria/genética , Diabetes Mellitus Tipo 2/genética , Nefropatías Diabéticas/genética , Túbulos Renales/metabolismo , Adulto , Anciano , Albuminuria/etiología , Animales , Catepsina C/genética , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas/etiología , Femenino , Técnicas de Inactivación de Genes , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Riñón/metabolismo , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Ratas , Receptores de Superficie Celular/genética , Sulfotransferasas/genética , Proteínas de Unión al GTP rab/genética , Proteínas de Unión al GTP rab/metabolismo
5.
Exp Gerontol ; 74: 1-8, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26657493

RESUMEN

OBJECTIVE: Telomere length (TL) has been proposed as a biomarker of ageing, which might be used to identify individuals at higher risk of age-related diseases. Obesity is a well-known risk factor for several diseases. This study aims to analyse the associations of BMI with TL and the rate of TL change in older adults. METHODS: Leukocyte TL (LTL) was measured by quantitative PCR in blood samples of 3600 older adults aged 50-75 years obtained at the baseline examination of a population-based cohort study in Germany. For longitudinal analyses, measurements were repeated in blood samples obtained at 8-year follow-up from 1000 participants. Multivariate linear regression models were used to estimate associations of BMI with LTL and changes in LTL over time. RESULTS: LTL was inversely associated with age (r = -0.090, p < 0.0001). BMI and LTL associations varied according to age (p for interaction = 0.021). BMI was significantly inversely associated with LTL in those younger than 60 years (-6 basepairs per 1 kg/m(2) difference in BMI). In particular, weight gain during adulthood was inversely associated with LTL in a dose-response manner in this age group, with those having gained ≥ 30 kg having significantly shorter telomeres (-209 basepairs) than those who maintained their weight. No clear patterns were observed between any of BMI-related variables and the rate of LTL change. CONCLUSIONS: Our cross-sectional analysis supports suggestions that weight gain during adulthood and obesity may contribute to shorter telomere length below 60 years of age, but this relationship could not be shown longitudinally.


Asunto(s)
Envejecimiento/genética , Índice de Masa Corporal , Obesidad/genética , Obesidad/fisiopatología , Acortamiento del Telómero , Telómero/genética , Adiposidad , Factores de Edad , Anciano , Envejecimiento/sangre , Estudios Transversales , Femenino , Alemania , Humanos , Leucocitos/metabolismo , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Obesidad/sangre , Obesidad/diagnóstico , Reacción en Cadena de la Polimerasa , Factores de Riesgo , Telómero/metabolismo , Factores de Tiempo , Aumento de Peso
6.
Exp Gerontol ; 70: 18-25, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26255046

RESUMEN

BACKGROUND & AIMS: Leukocyte telomere length (LTL) shortens with age and short LTL has been associated with increased mortality and increased risk for some age-related outcomes. This study aims to analyse the associations of smoking habits with LTL and rate of LTL change per year in older adults. METHODS: LTL was measured by quantitative PCR at baseline in 3600 older adults, who were enrolled in a population-based cohort study in Germany. For longitudinal analyses, measurements were repeated in blood samples obtained at 8-year follow-up from 1000 participants. Terminal Restriction Fragment analysis was additionally performed in a sub-sample to obtain absolute LTL in base pairs. Multivariate linear regression models were used to estimate associations of smoking habits with baseline LTL and changes in LTL over time. RESULTS: LTL was inversely associated with age (r=-0.090, p<0.0001). Women had longer LTL than men (p<0.0001). Smoking was inversely associated with LTL. On average, current smokers had 73 base pairs (BP) shorter LTL compared to never smokers. Smoking intensity and pack-years of smoking were also inversely associated with LTL, and a positive association was observed with years since smoking cessation. Slower LTL attrition rates were observed in ever smokers over 8years of follow-up. CONCLUSIONS: Our cross-sectional analysis supports suggestions that smoking might contribute to shortening of LTL but this relationship could not be shown longitudinally. The overall rather small effect sizes observed for smoking-related variables suggest that LTL reflects smoking-related health hazards only to a very limited extent.


Asunto(s)
Envejecimiento/genética , Leucocitos/ultraestructura , Fumar/genética , Homeostasis del Telómero/fisiología , Anciano , Envejecimiento/sangre , Estudios Transversales , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Fumar/sangre , Telómero/fisiología , Acortamiento del Telómero/fisiología
7.
Gerontology ; 61(5): 407-15, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25924722

RESUMEN

BACKGROUND: Oxidative stress (OS) and inflammatory biomarkers have been postulated to be important factors in the development of age-related diseases. While causes of frailty are complex and multidimensional based on the interaction of genetic, biological, physical, and environmental factors, the biological basis of frailty has been difficult to establish. OBJECTIVE: In this study, we aimed to assess the possible association between different OS and inflammatory biomarkers and frailty. METHODS: This cross-sectional analysis was performed among 2,518 subjects participating in a large population-based cohort study on aging conducted in Germany. Frailty was assessed as proposed by Fried et al. [J Gerontol A Biol Sci Med Sci 2001;56:M146-M156]. OS biomarkers, biological antioxidant potential (BAP), derivate of reactive oxygen metabolites (d-ROM) and total thiol levels (TTL), and an established biomarker of inflammation C-reactive protein (CRP) were measured by spectrophotometry and immunoturbidimetry. Logistic regression models were performed to assess the relationship between the OS biomarkers and frailty status. Odds ratios (OR) and 95% confidence intervals (CI) were calculated to quantify the associations. RESULTS: Mean levels of d-ROM, TTL, and CRP differed between frail and non-frail participants (p values <0.0001). Comparing highest and lowest quartiles of the biomarkers, statistically significant positive associations with frailty were observed for d-ROM (OR: 2.02, 95% CI: 1.25-3.25) and CRP (OR: 3.15, 95% CI: 2.00-4.96), respectively, after controlling for age and sex. An inverse statistically significant association with frailty was observed for TTL (OR: 0.42, 95% CI: 0.25-0.69). CONCLUSION: The strong associations with OS biomarkers and CRP support a major role of OS and inflammation in the development of frailty, which should be followed up in further longitudinal studies on frailty.


Asunto(s)
Anciano Frágil , Estrés Oxidativo , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Estudios de Cohortes , Estudios Transversales , Femenino , Alemania , Humanos , Mediadores de Inflamación/sangre , Modelos Logísticos , Masculino , Especies Reactivas de Oxígeno/sangre , Compuestos de Sulfhidrilo/sangre
8.
Int J Cancer ; 137(9): 2175-83, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-25940397

RESUMEN

A small number of common susceptibility loci have been identified for pancreatic cancer, one of which is marked by rs401681 in the TERT-CLPTM1L gene region on chromosome 5p15.33. Because this region is characterized by low linkage disequilibrium, we sought to identify whether additional single nucleotide polymorphisms (SNPs) could be related to pancreatic cancer risk, independently of rs401681. We performed an in-depth analysis of genetic variability of the telomerase reverse transcriptase (TERT) and the telomerase RNA component (TERC) genes, in 5,550 subjects with pancreatic cancer and 7,585 controls from the PANcreatic Disease ReseArch (PANDoRA) and the PanScan consortia. We identified a significant association between a variant in TERT and pancreatic cancer risk (rs2853677, odds ratio = 0.85; 95% confidence interval = 0.80-0.90, p = 8.3 × 10(-8)). Additional analysis adjusting rs2853677 for rs401681 indicated that the two SNPs are independently associated with pancreatic cancer risk, as suggested by the low linkage disequilibrium between them (r(2) = 0.07, D' = 0.28). Three additional SNPs in TERT reached statistical significance after correction for multiple testing: rs2736100 (p = 3.0 × 10(-5) ), rs4583925 (p = 4.0 × 10(-5) ) and rs2735948 (p = 5.0 × 10(-5) ). In conclusion, we confirmed that the TERT locus is associated with pancreatic cancer risk, possibly through several independent variants.


Asunto(s)
Carcinoma Ductal Pancreático/genética , Neoplasias Pancreáticas/genética , Telomerasa/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Humanos , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Mutación , Polimorfismo de Nucleótido Simple , Adulto Joven
9.
J Natl Cancer Inst ; 107(5)2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25873736

RESUMEN

BACKGROUND: Recent meta-analyses show strong evidence of associations among genetic variants in CHRNA5 on chromosome 15q25, smoking quantity, and lung cancer. This meta-analysis tests whether the CHRNA5 variant rs16969968 predicts age of smoking cessation and age of lung cancer diagnosis. METHODS: Meta-analyses examined associations between rs16969968, age of quitting smoking, and age of lung cancer diagnosis in 24 studies of European ancestry (n = 29 072). In each dataset, we used Cox regression models to evaluate the association between rs16969968 and the two primary phenotypes (age of smoking cessation among ever smokers and age of lung cancer diagnosis among lung cancer case patients) and the secondary phenotype of smoking duration. Heterogeneity across studies was assessed with the Cochran Q test. All statistical tests were two-sided. RESULTS: The rs16969968 allele (A) was associated with a lower likelihood of smoking cessation (hazard ratio [HR] = 0.95, 95% confidence interval [CI] = 0.91 to 0.98, P = .0042), and the AA genotype was associated with a four-year delay in median age of quitting compared with the GG genotype. Among smokers with lung cancer diagnoses, the rs16969968 genotype (AA) was associated with a four-year earlier median age of diagnosis compared with the low-risk genotype (GG) (HR = 1.08, 95% CI = 1.04 to 1.12, P = 1.1*10(-5)). CONCLUSION: These data support the clinical significance of the CHRNA5 variant rs16969968. It predicts delayed smoking cessation and an earlier age of lung cancer diagnosis in this meta-analysis. Given the existing evidence that this CHRNA5 variant predicts favorable response to cessation pharmacotherapy, these findings underscore the potential clinical and public health importance of rs16969968 in CHRNA5 in relation to smoking cessation success and lung cancer risk.


Asunto(s)
Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/etiología , Proteínas del Tejido Nervioso/genética , Receptores Nicotínicos/genética , Cese del Hábito de Fumar , Fumar/genética , Variación Genética , Humanos , Neoplasias Pulmonares/genética , Persona de Mediana Edad , Fenotipo , Factores de Riesgo , Fumar/efectos adversos , Cese del Hábito de Fumar/estadística & datos numéricos , Factores de Tiempo
10.
Hum Mol Genet ; 24(10): 2966-84, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25652398

RESUMEN

We recently identified a novel susceptibility variant, rs865686, for estrogen-receptor positive breast cancer at 9q31.2. Here, we report a fine-mapping analysis of the 9q31.2 susceptibility locus using 43 160 cases and 42 600 controls of European ancestry ascertained from 52 studies and a further 5795 cases and 6624 controls of Asian ancestry from nine studies. Single nucleotide polymorphism (SNP) rs676256 was most strongly associated with risk in Europeans (odds ratios [OR] = 0.90 [0.88-0.92]; P-value = 1.58 × 10(-25)). This SNP is one of a cluster of highly correlated variants, including rs865686, that spans ∼14.5 kb. We identified two additional independent association signals demarcated by SNPs rs10816625 (OR = 1.12 [1.08-1.17]; P-value = 7.89 × 10(-09)) and rs13294895 (OR = 1.09 [1.06-1.12]; P-value = 2.97 × 10(-11)). SNP rs10816625, but not rs13294895, was also associated with risk of breast cancer in Asian individuals (OR = 1.12 [1.06-1.18]; P-value = 2.77 × 10(-05)). Functional genomic annotation using data derived from breast cancer cell-line models indicates that these SNPs localise to putative enhancer elements that bind known drivers of hormone-dependent breast cancer, including ER-α, FOXA1 and GATA-3. In vitro analyses indicate that rs10816625 and rs13294895 have allele-specific effects on enhancer activity and suggest chromatin interactions with the KLF4 gene locus. These results demonstrate the power of dense genotyping in large studies to identify independent susceptibility variants. Analysis of associations using subjects with different ancestry, combined with bioinformatic and genomic characterisation, can provide strong evidence for the likely causative alleles and their functional basis.


Asunto(s)
Neoplasias de la Mama/genética , Cromosomas Humanos Par 9 , Sitios Genéticos , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Adulto , Anciano , Pueblo Asiatico/genética , Mapeo Cromosómico , Elementos de Facilitación Genéticos , Receptor alfa de Estrógeno/genética , Femenino , Factor de Transcripción GATA3/genética , Estudios de Asociación Genética , Factor Nuclear 3-alfa del Hepatocito/genética , Humanos , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/genética , Persona de Mediana Edad , Riesgo , Población Blanca/genética
11.
Int J Cancer ; 136(6): E685-96, 2015 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-25227710

RESUMEN

A large genotyping project within the Breast Cancer Association Consortium (BCAC) recently identified 41 associations between single nucleotide polymorphisms (SNPs) and overall breast cancer (BC) risk. We investigated whether the effects of these 41 SNPs, as well as six SNPs associated with estrogen receptor (ER) negative BC risk are modified by 13 environmental risk factors for BC. Data from 22 studies participating in BCAC were pooled, comprising up to 26,633 cases and 30,119 controls. Interactions between SNPs and environmental factors were evaluated using an empirical Bayes-type shrinkage estimator. Six SNPs showed interactions with associated p-values (pint ) <1.1 × 10(-3) . None of the observed interactions was significant after accounting for multiple testing. The Bayesian False Discovery Probability was used to rank the findings, which indicated three interactions as being noteworthy at 1% prior probability of interaction. SNP rs6828523 was associated with increased ER-negative BC risk in women ≥170 cm (OR = 1.22, p = 0.017), but inversely associated with ER-negative BC risk in women <160 cm (OR = 0.83, p = 0.039, pint = 1.9 × 10(-4) ). The inverse association between rs4808801 and overall BC risk was stronger for women who had had four or more pregnancies (OR = 0.85, p = 2.0 × 10(-4) ), and absent in women who had had just one (OR = 0.96, p = 0.19, pint = 6.1 × 10(-4) ). SNP rs11242675 was inversely associated with overall BC risk in never/former smokers (OR = 0.93, p = 2.8 × 10(-5) ), but no association was observed in current smokers (OR = 1.07, p = 0.14, pint = 3.4 × 10(-4) ). In conclusion, recently identified BC susceptibility loci are not strongly modified by established risk factors and the observed potential interactions require confirmation in independent studies.


Asunto(s)
Neoplasias de la Mama/genética , Interacción Gen-Ambiente , Predisposición Genética a la Enfermedad , Neoplasias de la Mama/química , Neoplasias de la Mama/etiología , Femenino , Sitios Genéticos , Humanos , Polimorfismo de Nucleótido Simple , Receptores de Estrógenos/análisis , Factores de Riesgo
12.
Int J Cancer ; 136(5): E351-8, 2015 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-25066524

RESUMEN

Compelling biological and epidemiological evidences point to a key role of genetic variants of the TERT and TERC genes in cancer development. We analyzed the genetic variability of these two gene regions using samples of 2,267 multiple myeloma (MM) cases and 2,796 healthy controls. We found that a TERT variant, rs2242652, is associated with reduced MM susceptibility (OR = 0.81; 95% CI: 0.72-0.92; p = 0.001). In addition we measured the leukocyte telomere length (LTL) in a subgroup of 140 cases who were chemotherapy-free at the time of blood donation and 468 controls, and found that MM patients had longer telomeres compared to controls (OR = 1.19; 95% CI: 0.63-2.24; p(trend) = 0.01 comparing the quartile with the longest LTL versus the shortest LTL). Our data suggest the hypothesis of decreased disease risk by genetic variants that reduce the efficiency of the telomerase complex. This reduced efficiency leads to shorter telomere ends, which in turn may also be a marker of decreased MM risk.


Asunto(s)
Mieloma Múltiple/genética , Polimorfismo Genético/genética , Telomerasa/genética , Homeostasis del Telómero/genética , Anciano , Estudios de Casos y Controles , Estudios de Cohortes , Biología Computacional , Femenino , Estudios de Seguimiento , Predisposición Genética a la Enfermedad , Alemania/epidemiología , Humanos , Leucocitos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/epidemiología , Pronóstico , Factores de Riesgo
13.
J Gerontol A Biol Sci Med Sci ; 70(4): 518-24, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25070660

RESUMEN

BACKGROUND: The free radical/oxidative stress theory of aging has recently received much attention but the association of oxidative stress markers with all-cause mortality was not yet assessed in humans. METHODS: We measured derivatives of reactive oxygen metabolites (d-ROM) as a proxy for the reactive oxygen species concentration and total thiol levels (TTL) as a proxy for the redox control status in 2,932 participants of a population-based cohort study from Germany. RESULTS: The median age of the population was 70 years and 120 (4.1%) study participants died during a mean follow-up of 3.3 years. Compared with the bottom tertiles, the top tertiles of d-ROM and TTL concentrations were both associated with all-cause mortality in models adjusted for age, sex, education, smoking, physical activity, and alcohol consumption (hazard ratios and 95% confidence intervals: 1.63 [1.01; 2.63] and 0.68 [0.53; 0.87], respectively). Adding diseases, the inflammatory marker C-reactive protein or a cumulative somatic morbidity index did not alter the results for TTL. However, the association of d-ROM and mortality was attenuated and no longer statistically significant after adding C-reactive protein and the somatic morbidity index to the model. CONCLUSIONS: This study adds epidemiological evidence to the free radical/oxidative stress theory of aging. Both d-ROM and TTL were associated with mortality at older age. For TTL, this association was independent of baseline health status. Inflammation and higher general morbidity could be intermediate states on the pathway from high d-ROM levels to mortality. This hypothesis should to be explored by future studies with repeated measurements.


Asunto(s)
Envejecimiento , Proteína C-Reactiva/metabolismo , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/mortalidad , Longevidad , Estrés Oxidativo , Anciano , Biomarcadores/metabolismo , Enfermedades Cardiovasculares/diagnóstico , Causas de Muerte , HDL-Colesterol/sangre , Estudios de Cohortes , Creatinina/sangre , Femenino , Estudios de Seguimiento , Alemania/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Especies Reactivas de Oxígeno/sangre , Factores de Riesgo , Sensibilidad y Especificidad , Compuestos de Sulfhidrilo/sangre , Encuestas y Cuestionarios , Triglicéridos/sangre
14.
Exp Gerontol ; 58: 250-5, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25150678

RESUMEN

Both telomere length and frailty were observed to be associated with aging. Whether and to what extent telomere length is related to frailty is essentially unknown. In this cross-sectional analysis of baseline data of 3537 community-dwelling adults aged 50 to 75 years of a large German cohort study, we assessed the hypothesis that shorter telomere length might be a biological marker for frailty. Using whole blood DNA we examined mean telomere repeat copy to single gene copy number (T/S ratio) using quantitative PCR. Construction of a frailty index (FI) was based on a deficit accumulation approach, which quantifies frailty as ratio of the deficits present divided by the total number of deficits considered. Mean FI was determined according to age by tertiles of T/S ratio. Furthermore, we used correlation analyses stratified for gender and age groups to examine the association of the T/S ratio with frailty. Mean FI value was similar across tertiles of the T/S ratio (0.24±0.14, 0.24±0.14 and 0.23±0.14, respectively (p=0.09)), and FI and the T/S ratio were uncorrelated in gender- and age-specific analyses. In conclusion, T/S ratio and frailty were unrelated in this large sample of older adults. T/S ratio may therefore not be a meaningful biological marker for frailty.


Asunto(s)
Envejecimiento/genética , Anciano Frágil , Acortamiento del Telómero , Telómero/genética , Distribución por Edad , Factores de Edad , Anciano , Envejecimiento/metabolismo , Estudios Transversales , Femenino , Dosificación de Gen , Marcadores Genéticos , Evaluación Geriátrica/métodos , Alemania , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Valor Predictivo de las Pruebas , Distribución por Sexo , Factores Sexuales , Telómero/metabolismo
15.
Breast Cancer Res ; 16(3): R51, 2014 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-24887515

RESUMEN

INTRODUCTION: We have previously shown that a tag single nucleotide polymorphism (rs10235235), which maps to the CYP3A locus (7q22.1), was associated with a reduction in premenopausal urinary estrone glucuronide levels and a modest reduction in risk of breast cancer in women age ≤50 years. METHODS: We further investigated the association of rs10235235 with breast cancer risk in a large case control study of 47,346 cases and 47,570 controls from 52 studies participating in the Breast Cancer Association Consortium. Genotyping of rs10235235 was conducted using a custom Illumina Infinium array. Stratified analyses were conducted to determine whether this association was modified by age at diagnosis, ethnicity, age at menarche or tumor characteristics. RESULTS: We confirmed the association of rs10235235 with breast cancer risk for women of European ancestry but found no evidence that this association differed with age at diagnosis. Heterozygote and homozygote odds ratios (ORs) were OR = 0.98 (95% CI 0.94, 1.01; P = 0.2) and OR = 0.80 (95% CI 0.69, 0.93; P = 0.004), respectively (P(trend) = 0.02). There was no evidence of effect modification by tumor characteristics. rs10235235 was, however, associated with age at menarche in controls (P(trend) = 0.005) but not cases (P(trend) = 0.97). Consequently the association between rs10235235 and breast cancer risk differed according to age at menarche (P(het) = 0.02); the rare allele of rs10235235 was associated with a reduction in breast cancer risk for women who had their menarche age ≥15 years (OR(het) = 0.84, 95% CI 0.75, 0.94; OR(hom) = 0.81, 95% CI 0.51, 1.30; P(trend) = 0.002) but not for those who had their menarche age ≤11 years (OR(het) = 1.06, 95% CI 0.95, 1.19, OR(hom) = 1.07, 95% CI 0.67, 1.72; P(trend) = 0.29). CONCLUSIONS: To our knowledge rs10235235 is the first single nucleotide polymorphism to be associated with both breast cancer risk and age at menarche consistent with the well-documented association between later age at menarche and a reduction in breast cancer risk. These associations are likely mediated via an effect on circulating hormone levels.


Asunto(s)
Neoplasias de la Mama/genética , Citocromo P-450 CYP3A/genética , Estudios de Asociación Genética , Menarquia/genética , Adulto , Factores de Edad , Edad de Inicio , Anciano , Neoplasias de la Mama/patología , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Premenopausia/genética , Historia Reproductiva , Factores de Riesgo , Población Blanca
16.
Lancet Diabetes Endocrinol ; 2(9): 719-29, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24974252

RESUMEN

BACKGROUND: Low plasma 25-hydroxyvitamin D (25[OH]D) concentration is associated with high arterial blood pressure and hypertension risk, but whether this association is causal is unknown. We used a mendelian randomisation approach to test whether 25(OH)D concentration is causally associated with blood pressure and hypertension risk. METHODS: In this mendelian randomisation study, we generated an allele score (25[OH]D synthesis score) based on variants of genes that affect 25(OH)D synthesis or substrate availability (CYP2R1 and DHCR7), which we used as a proxy for 25(OH)D concentration. We meta-analysed data for up to 108 173 individuals from 35 studies in the D-CarDia collaboration to investigate associations between the allele score and blood pressure measurements. We complemented these analyses with previously published summary statistics from the International Consortium on Blood Pressure (ICBP), the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium, and the Global Blood Pressure Genetics (Global BPGen) consortium. FINDINGS: In phenotypic analyses (up to n=49 363), increased 25(OH)D concentration was associated with decreased systolic blood pressure (ß per 10% increase, -0·12 mm Hg, 95% CI -0·20 to -0·04; p=0·003) and reduced odds of hypertension (odds ratio [OR] 0·98, 95% CI 0·97-0·99; p=0·0003), but not with decreased diastolic blood pressure (ß per 10% increase, -0·02 mm Hg, -0·08 to 0·03; p=0·37). In meta-analyses in which we combined data from D-CarDia and the ICBP (n=146 581, after exclusion of overlapping studies), each 25(OH)D-increasing allele of the synthesis score was associated with a change of -0·10 mm Hg in systolic blood pressure (-0·21 to -0·0001; p=0·0498) and a change of -0·08 mm Hg in diastolic blood pressure (-0·15 to -0·02; p=0·01). When D-CarDia and consortia data for hypertension were meta-analysed together (n=142 255), the synthesis score was associated with a reduced odds of hypertension (OR per allele, 0·98, 0·96-0·99; p=0·001). In instrumental variable analysis, each 10% increase in genetically instrumented 25(OH)D concentration was associated with a change of -0·29 mm Hg in diastolic blood pressure (-0·52 to -0·07; p=0·01), a change of -0·37 mm Hg in systolic blood pressure (-0·73 to 0·003; p=0·052), and an 8·1% decreased odds of hypertension (OR 0·92, 0·87-0·97; p=0·002). INTERPRETATION: Increased plasma concentrations of 25(OH)D might reduce the risk of hypertension. This finding warrants further investigation in an independent, similarly powered study. FUNDING: British Heart Foundation, UK Medical Research Council, and Academy of Finland.


Asunto(s)
Colestanotriol 26-Monooxigenasa/genética , Hipertensión/prevención & control , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/genética , Polimorfismo de Nucleótido Simple , Deficiencia de Vitamina D/prevención & control , Vitamina D/análogos & derivados , Adulto , Índice de Masa Corporal , Familia 2 del Citocromo P450 , Femenino , Predisposición Genética a la Enfermedad , Humanos , Hipertensión/sangre , Hipertensión/genética , Masculino , Análisis de la Aleatorización Mendeliana , Persona de Mediana Edad , Fenotipo , Ensayos Clínicos Controlados Aleatorios como Asunto , Vitamina D/administración & dosificación , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/genética
17.
Hum Mol Genet ; 23(22): 6096-111, 2014 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-24943594

RESUMEN

Candidate variant association studies have been largely unsuccessful in identifying common breast cancer susceptibility variants, although most studies have been underpowered to detect associations of a realistic magnitude. We assessed 41 common non-synonymous single-nucleotide polymorphisms (nsSNPs) for which evidence of association with breast cancer risk had been previously reported. Case-control data were combined from 38 studies of white European women (46 450 cases and 42 600 controls) and analyzed using unconditional logistic regression. Strong evidence of association was observed for three nsSNPs: ATXN7-K264R at 3p21 [rs1053338, per allele OR = 1.07, 95% confidence interval (CI) = 1.04-1.10, P = 2.9 × 10(-6)], AKAP9-M463I at 7q21 (rs6964587, OR = 1.05, 95% CI = 1.03-1.07, P = 1.7 × 10(-6)) and NEK10-L513S at 3p24 (rs10510592, OR = 1.10, 95% CI = 1.07-1.12, P = 5.1 × 10(-17)). The first two associations reached genome-wide statistical significance in a combined analysis of available data, including independent data from nine genome-wide association studies (GWASs): for ATXN7-K264R, OR = 1.07 (95% CI = 1.05-1.10, P = 1.0 × 10(-8)); for AKAP9-M463I, OR = 1.05 (95% CI = 1.04-1.07, P = 2.0 × 10(-10)). Further analysis of other common variants in these two regions suggested that intronic SNPs nearby are more strongly associated with disease risk. We have thus identified a novel susceptibility locus at 3p21, and confirmed previous suggestive evidence that rs6964587 at 7q21 is associated with risk. The third locus, rs10510592, is located in an established breast cancer susceptibility region; the association was substantially attenuated after adjustment for the known GWAS hit. Thus, each of the associated nsSNPs is likely to be a marker for another, non-coding, variant causally related to breast cancer risk. Further fine-mapping and functional studies are required to identify the underlying risk-modifying variants and the genes through which they act.


Asunto(s)
Neoplasias de la Mama/genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Proteínas de Anclaje a la Quinasa A/genética , Adulto , Alelos , Ataxina-7 , Estudios de Casos y Controles , Proteínas del Citoesqueleto/genética , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Persona de Mediana Edad , Quinasas Relacionadas con NIMA , Proteínas del Tejido Nervioso/genética , Proteínas Serina-Treonina Quinasas/genética
18.
Eur J Epidemiol ; 29(3): 171-9, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24671603

RESUMEN

The frailty index (FI), defined by a deficit accumulation approach, has emerged as a promising concept in gerontological research, but applications have been mostly restricted to populations from Canada and the United States aged 65 years or older. Baseline data from the German ESTHER cohort study (N 9,886; age 50-75; mean follow-up 8.7 years) were used to create a FI through a deficit accumulation approach. For estimation of frailty prevalence, we used cut-points for the FI to define three categories (non-frail 0 to ≤0.20; pre-frail >0.20 to <0.45; frail ≥0.45). We assessed variation of the FI by age and sex: 10-year survival according to baseline FI was assessed by Kaplan-Meier curves and bivariate and multivariate Cox proportional hazard models. Cubic splines were used to assess sex-specific dose-response associations. Prevalence of frailty was 9.2 and 10.5% in women and men, respectively. Age-specific prevalence of frailty ranged from 4.6% in 50-54 year old participants to 17.0% in 70-75 year old participants. Below 60 years of age, men had a higher FI than women. However, the FI showed a stronger increase with age among women (3.1% per year) than among men (1.7% per year) and was higher among women than men in older age groups. Adjusted hazard ratios (95% confidence intervals) for all-cause mortality were 1.08 (0.84-1.39), 1.32 (1.05-1.66), 1.77 (1.41-2.22), and 2.60 (2.11-3.20) for the 2nd, 3rd, 4th, and 5th quintile of the FI compared to 1st quintile, respectively. There was a strong dose-response relationship between the FI and total mortality among both men and women and both younger (<65 years) and older subjects. We found sex differences in the FI and its increase with age, along with a consistent strong association of the FI with mortality in both sexes, even for age group 50-64.


Asunto(s)
Anciano Frágil/estadística & datos numéricos , Evaluación Geriátrica/métodos , Mortalidad , Distribución por Edad , Anciano , Estudios de Cohortes , Femenino , Alemania/epidemiología , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Vigilancia de la Población , Prevalencia , Modelos de Riesgos Proporcionales , Distribución por Sexo , Factores Socioeconómicos , Factores de Tiempo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...