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

Otitis media microbes: culture, PCR, and confocal laser scanning microscopy

Otitis media microbes: culture, PCR, and confocal laser scanning microscopy Objectives: To assess the presence of middle ear pathogens in nasopharynx (NP), middle ear fluid (MEF), and middle ear mucosal swabs (MES) of 14 patients undergoing middle car sur cry. Methodology: Bacteria were assessed by culture and species specific PCR. Biofilm was investigated by confocal laser scanning microscopy (CLSM) of middle ear biopsies (MEBs). Results: Bacteria were absent in CLSM of MEBs in three of the four closed and healthy middle ears. Bacteria occurred in the ear with a foreign body (middle ear prosthesis), which showed localized living and dead bacteria, indicating biofilm. Bacterial growth was present in ten patient ears, but biofilm occurred in only one patient. CLSM indicated biofilm in the middle ear of two patients for whom PCR detected Haemophilus influenzae in the MEF. The three classical pathogens could frequently be found in the nasopharynx, by culture and PCR, but not from the middle ear. Alloiococcus otitidis was detected in the MEF of all five patients with open inflamed ears, though virtually absent from the nasopharynx. Pseudomonas aeruginosa was present in seven. It was the only pathogen found oil several occasions in all three locations in one patient. Conclusions: This study confirms the association of H. influenzae with middle ear biofilm, and indicates a potential role of P aeruginosa in middle ear inflammation and biofilm formation. Biofilm does not seem to cause inflammation. It is unclear whether the predominance of A. otitidis in chronically inflamed open middle ears indicates a pathogenic or contaminant role for this organism

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

Familial aggregation of tinnitus: a European multicentre study.

Item does not contain fulltextINTRODUCTION AND AIM: Tinnitus is a common condition affecting approximately 20% of the older population. There is increasing evidence that changes in the central auditory system following cochlear malfunctioning are responsible for tinnitus. To date, few investigators have studied the influence of genetic factors on tinnitus. The present report investigates the presence of a familial effect in tinnitus subjects. METHODS: In a European multicentre study, 198 families were recruited in seven European countries. Each family had at least 3 siblings. Subjects were screened for causes of hearing loss other than presbyacusis by clinical examination and a questionnaire. The presence of tinnitus was evaluated with the question "Nowadays, do you ever get noises in your head or ear (tinnitus) which usually last longer than five minutes". Familial aggregation was tested using three methods: a mixed model approach, calculating familial correlations, and estimating the risk of a subject having tinnitus if the disorder is present in another family member. RESULTS: All methods demonstrated a significant familial effect for tinnitus. The effect persisted after correction for the effect of other risk factors such as hearing loss, gender and age. The size of the familial effect is smaller than that for age-related hearing impairment, with a familial correlation of 0.15. CONCLUSION: The presence of a familial effect for tinnitus opens the door to specific studies that can determine whether this effect is due to a shared familial environment or the involvement of genetic factors. Subsequent association studies may result in the identification of the factors responsible. In addition, more emphasis should be placed on the effect of role models in the treatment of tinnitus

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.