Occupational Noise, Smoking, and a High Body Mass Index are Risk Factors for Age-related Hearing Impairment and Moderate Alcohol Consumption is Protective: A European Population-based Multicenter Study

A multicenter study was set up to elucidate the environmental and medical risk factors contributing to age-related hearing impairment (ARHI). Nine subsamples, collected by nine audiological centers across Europe, added up to a total of 4,083 subjects between 53 and 67 years. Audiometric data (pure-tone average [PTA]) were collected and the participants filled out a questionnaire on environmental risk factors and medical history. People with a history of disease that could affect hearing were excluded. PTAs were adjusted for age and sex and tested for association with exposure to risk factors. Noise exposure was associated with a significant loss of hearing at high sound frequencies (>1 kHz). Smoking significantly increased high-frequency hearing loss, and the effect was dose-dependent. The effect of smoking remained significant when accounting for cardiovascular disease events. Taller people had better hearing on average with a more pronounced effect at low sound frequencies (<2 kHz). A high body mass index (BMI) correlated with hearing loss across the frequency range tested. Moderate alcohol consumption was inversely correlated with hearing loss. Significant associations were found in the high as well as in the low frequencies. The results suggest that a healthy lifestyle can protect against age-related hearing impairment

The awareness of having a family history of hearing problems and the impact on those with hearing difficulties themselves: A questionnaire

In the recent past, the number of studies on genetic aspects of hearing loss has risen rapidly. Despite this, the specific impact of the family history of hearing loss on those having hearing loss themselves is still a relatively unexplored area of research. This study investigates the impact of a family history of hearing loss in relation to awareness of that history. The aim was to empirically identify the number and the nature of the underlying constructs in the domain of family history of hearing loss. A structured 20-item questionnaire was designed. Responses were obtained from 192 adults with late onset non-syndromal hearing loss. The ages ranged from 17 to 92 years (mean 60.4 years, SD 13.9). An exploratory factor analysis was performed and the psychometric features of the scales were examined. Multiple regression analyses were performed to investigate the association between the impact of a family history of hearing loss and the awareness of that history, demographic variables and audiometric measures. Factor analyses confirmed the existence of two main factors: role modelling, distress and concern; and three minor factors: distress from hearing loss per se, importance of own hearing loss and distinctiveness of individual hearing. Awareness of family history was significantly associated with role modelling. Severity of hearing loss was significantly related to distress and concern. The results are discussed in terms of the themes identified, the utility of the questionnaire and the utility of family history and role-modelling in clinical care. The concept of family history of hearing loss and making people aware of it by identifying and introducing suitable role models deserves further attention both in research and in clinical practice

Integración de teoría simulación y práctica de laboratorio en asignaturas de Ingeniería Eléctrica

Desde hace mucho tiempo se está intentando promover cambios en la educación de la ingeniería. La desregulación de la industria eléctrica también está causando cambios en los tipos de trabajos a los que acceden los ingenieros después de terminar sus estudios. Este trabajo describe algunos de los esfuerzos de los profesores de Ingeniería Eléctrica de la Universidad de Cantabria, por ofrecer a los estudiantes una experiencia de aprendizaje más activa en el área de los circuitos y las maquinas eléctricas. Asimismo, se presenta un resumen del plan de estudios del nuevo Grado en Ingeniería Eléctrica. Los cursos afectados son uno de circuitos eléctricos y otro de conversión de energía, ambos obligatorios para todos los estudiantes del Grado en Ingeniería Eléctrica. Se proporciona la metodología a seguir en la impartición de las asignaturas, así como las tareas que los estudiantes deben realizar. También se presentan observaciones y análisis sobre las experiencias implementadas. En el documento se describe el trabajo realizado con el objetivo de convertir a los cursos tradicionales de ingeniería eléctrica en cursos en los que el aprendizaje pueda fluir con facilidad de la clase magistral al laboratorio o al software de simulación

Should Firms be Allowed to Indemnify Their Employees for Sanctions?

Policymakers have questioned whether firms should be allowed to indemnify their employees for personal sanctions for corporate crimes. This article provides the first formal analysis of this form of indemnification. Targeting employees with unindemnifiable sanctions carries the social cost of exposing employees of law-abiding firms to the risk of mistaken government prosecution. Deterrence is typically achieved more efficiently by sanctioning the firm alone. We find the circumstances under which the government should additionally sanction employees to be quite limited and the circumstances under which the government should ban indemnification of these sanctions to be more limited still. One circumstance is when an unindemnifiable employee sanction provides prosecutors with leverage to adjust the employee's sanction in exchange for his cooperation against the firm. (JEL K22, D82, L20) The Author 2009. Published by Oxford University Press on behalf of Yale University. All rights reserved. For permissions, please email: [email protected], Oxford University Press.

Familial aggregation of pure tone hearing thresholds in an aging European population

Objective: To investigate the familial correlations and intraclass correlation of age-related hearing impairment (ARHI) in specific frequencies. In addition, heritability estimates were calculated. Study Design: Multicenter survey in 8 European centers. Subjects: One hundred ninety-eight families consisting of 952 family members, screened by otologic examination and structured interviews. Subjects with general conditions, known to affect hearing thresholds or known otologic cause were excluded from the study. Results: We detected familial correlation coefficients of 0.36, 0.37, 0.36, and 0.30 for 0.25, 0.5, 1, and 2 kHz, respectively, and correlation coefficients of 0.20 and 0.18 for 4 and 8 kHz, respectively. Variance components analyses showed that the proportion of the total variance attributable to family differences was between 0.32 and 0.40 for 0.25, 0.5, 1, and 2 kHz and below 0.20 for 4 and 8 kHz. When testing for homogeneity between sib pair types, we observed a larger familial correlation between female than male subjects. Heritability estimates ranged between 0.79 and 0.36 across the frequencies. Discussion: Our results indicate that there is a substantial shared familial effect in ARHI. We found that familial aggregation of ARHI is markedly higher in the low frequencies and that there is a trend toward higher familial aggregation in female compared with male subjects

NSC62605

Age-related hearing impairment (ARHI) is the most prevalent sensory impairment in the elderly. ARHI is a complex disease caused by an interaction between environmental and genetic factors. The contribution of various environmental factors has been relatively extensively studied. In contrast, investigations to identify the genetic risk factors have only recently been initiated. In this paper we describe the results of an associ-ation study performed on 2418 ARHI samples derived from nine centers from seven European countries. In 70 candidate genes, a total of 768 tag single nucleotide polymorphisms (SNPs) were selected based on HAPMAP data. These genes were chosen among the monogenic hearing loss genes identified in mice and men i

Genome-wide SNP-Based Linkage Scan Identifies a Locus on 8q24 for an Age-Related Hearing Impairment Trait

Age-related hearing impairment (ARHI), or presbycusis, is a very common multifactorial disorder. Despite the knowledge that genetics play an important role in the etiology of human ARHI as revealed by heritability studies, to date, its precise genetic determinants remain elusive. Here we report the results of a cross-sectional family-based genetic study employing audiometric data. By using principal component analysis, we were able to reduce the dimensionality of this multivariate phenotype while capturing most of the variation and retaining biologically important features of the audiograms. We conducted a genome-wide association as well as a linkage scan with high-density SNP microarrays. Because of the presence of genetic population substructure, association testing was stratified after which evidence was combined by meta-analysis. No association signals reaching genome-wide significance were detected. Linkage analysis identified a linkage peak on 8q24.13-q24.22 for a trait correlated to audiogram shape. The signal reached genome-wide significance, as assessed by simulations. This finding represents the first locus for an ARHI trait