Andrea Ciorba

The impact of hearing loss on the quality of life of elderly adults

Hearing loss is the most common sensory deficit in the elderly, and it is becoming a severe social and health problem. Especially in the elderly, hearing loss can impair the exchange of information, thus significantly impacting everyday life, causing loneliness, isolation, dependence, and frustration, as well as communication disorders. Due to the aging of the population in the developed world, presbycusis is a growing problem that has been reported to reduce quality of life (QoL). Progression of presbycusis cannot be remediated; therefore, optimal management of this condition not only requires early recognition and rehabilitation, but it also should include an evaluation of QoL status and its assessment.

Diabetes, Cardiovascular Risk Factors and Idiopathic Sudden Sensorineural Hearing Loss: A Case-Control Study

Aims/Hypothesis: Idiopathic sudden sensorineural hearing loss (ISSNHL) represents an acute inner ear disorder with an overall incidence of 5–20/100000 individuals per year in western countries. No clear causes for this disease have been found so far, but cochlear ischemia has been hypothesized as one of the etiopathological mechanisms. The aim of our study was to assess the role of diabetes and traditional cardiovascular risk factors in the pathogenesis of ISSNHL. Materials/Methods: Case-control study of 141 patients (75 males/66 females) matched for age and gender. Cases were affected by ISSNHL, defined as a sudden hearing loss ≧30 dB, within 3 frequencies, developing over 72 h. The control group was composed of 271 sex- and age-matched subjects (142 males/129 females) who agreed to participate in this observational study and provided blood samples for laboratory investigations. Cardiovascular risk factors examined were: diabetes mellitus, smoking history, hypercholesterolemia, hypertriglyceridemia and hypertension. Results: On the univariate analysis, diabetes prevalence was higher in the ISSNHL group (15.6%) compared to controls (8.5%) (p = 0.03). Also hypercholesterolemia was significantly more frequent in the ISSNHL group compared to the control population. There were no statistically significant differences between the 2 populations concerning other cardiovascular risk factors. The risk of ISSNHL tended to increase as the number of cardiovascular risk factors increased (p for linear trend = 0.018). Conclusions: Our findings suggest that diabetes mellitus, hypercholesterolemia and a high burden of cardiovascular risk factors are associated with the risk of ISSNHL.

Cochlear Repair by Transplantation of Human Cord Blood CD133+ Cells to Nod-Scid Mice Made Deaf with Kanamycin and Noise

We investigated the fate of human cord blood CD133+ hematopoietic stem cells (HSC) transplanted intravenously (IV) into irradiated nodscid mice previously made deaf by ototoxic treatment with kanamycin and/or intense noise, to verify whether HSC engraft the cochlea and contribute to inner ear restoration, in vivo. We tested the presence of HLA.DQα1 by PCR, used for traceability of engrafted cells, finding evidence that HSC migrated to various host tissues, including the organ of Corti (OC). By histology, antibody and lectin-staining analysis, we confirmed that HSC IV transplantation in mice previously damaged by ototoxic agents correlated with the repair process and stimulation ex novo of morphological recovery in the inner ear, while the cochlea of control oto-injured, nontransplanted mice remained seriously damaged. Dual color FISH analysis also provided evidence of positive engraftment in the inner ear and in various mouse tissues, also revealing small numbers of heterokaryons, probably derived from fusion of donor with endogenous cells, for up to 2 months following transplantation. These observations offer the first evidence that transplanted human HSC migrating to the inner ear of oto-injured mice may provide conditions for the resumption of deafened cochlea, emerging as a potential strategy for inner ear rehabilitation.

Environmental and genetic factors in age-related hearing impairment.

Age-related hearing impairment (ARHI), or presbycusis, is a complex disease with multifactorial etiology. It is the most prevalent sensory impairment in the elderly, and may have detrimental effects on their quality of life and psychological well-being. The aim of this paper is to give an overview of the current data on ARHI, focusing mainly on environmental agents and genetic predisposition in animal models and in humans. With improvement of our understanding of ARHI, treatment other than with amplification will be hopefully possible in the long term.

Tinnitus and cochlear implants

OBJECTIVE Several published studies seem to confirm the clinical observation that cochlear implants (CI) have a suppressive effect on tinnitus in most CI users. The aim of this paper is to present our personal experiences on tinnitus improvement after cochlear implantation. METHODS Before surgery, 51 post-lingually profoundly deaf adults, who underwent cochlear implantation between 2005 and 2007, filled out a questionnaire reporting tinnitus characteristics and the Italian version of the Tinnitus Handicap Inventory (THI-I). Moreover, they were asked to scale tinnitus loudness and annoyance. Six months after implant activation, patients repeated the same evaluations. Scores were statistically analysed by means of a Wilcoxon signed ranks test on the hypothesis that a CI could change the tinnitus magnitude and/or its annoyance. RESULTS In our series of 36 patients, 36.10% reported total loudness suppression and another 41.6% reported a reduction. Annoyance scores reduced in 75% of patients. THI reduced in 72.2% of patients. CONCLUSION Tinnitus reduction after CI may manifest as several mechanisms, such as habituation, acoustic masking, direct electrical nerve stimulation and cortical reorganization. Nevertheless, it is our opinion that data on CI benefits on tinnitus should be interpreted with caution and it seems reasonable to admit that further data is still necessary before considering CI as a treatment of tinnitus especially in unilateral deafness.

The diagnosis of autoimmune inner ear disease: evidence and critical pitfalls.

The purpose of this paper is to review the current diagnostic work-up for patients with suspected Autoimmune Inner Ear Disease (AIED). AIED is a rare disease accounting for less than 1% of all cases of hearing impairment or dizziness, characterized by a rapidly progressive, often fluctuating, bilateral SNHL over a period of weeks to months. While specific tests for autoimmunity to the inner ear would be valuable, at the time of writing, there are none that are both commercially available and proven to be useful. Thus far, most of the identified antigens lack a clear association with localized inner ear pathology and the diagnosis of AIED is based either on clinical criteria and/or on a positive response to steroids. For clinical practice, we recommend an antigen-non-specific test battery including blood test for autoimmune disorders and for conditions that resemble autoimmune disorders. Nevertheless, if financial resources are limited, a very restricted work-up study may have a similar efficiency.

Vertigo and autoimmunity

Autoimmune inner ear disease probably accounts for less than 1% of all cases of balance disorders, but its incidence is often overlooked due to the absence of a specific diagnostic test. Furthermore, in several systemic autoimmune diseases the vestibulo-cochlear system may be affected. Clinical features comprise generalized imbalance, ataxia, motion intolerance, episodic vertigo and positional vertigo. An autoimmune mechanism seems to be responsible for 6% of unilateral and 16% of bilateral forms of Ménière’s disease. Oscillopsia and disequilibrium secondary to a bilateral vestibular paresis are probably caused by an autoimmune response in 5% of cases. Balance disorders of central origin may be due to other immuno-mediated disorders such as multiple sclerosis, brainstem encephalitis and vasculitidis. Aim of this paper is to assess the clinical features of autoimmune vertigo disorders through a systematic literature review.

Cochlear implant in Cogan syndrome.

Abstract Conclusions: Despite the need for special fitting strategies, improvements in speech discrimination tests support the use of cochlear implantation (CI) for patients with Cogan syndrome. Adequate preimplant counselling is mandatory, to prevent high expectations and to stress the necessity for bilateral implantation. Objective: In 60% of patients with Cogan syndrome, CI remains the only treatment option. Literature data agree that once the electrode array is properly inserted, functional outcomes are very good. Nevertheless, results may deteriorate due to progressive cochlear ossification. A few studies have documented the outcomes of CI in these patients, but none have reported the long-term results. Methods: This was a retrospective study describing the outcomes of 3 implanted patients with Cogan syndrome – among 300 adult patients who received a cochlear implant, 3 had become deaf due to Cogan syndrome. Results: In one patient the cochlear ossification advanced and the speech perception abilities worsened from the highest category to identification of words in closed set. The second patient complained of an abrupt reduction of loudness at 18 months post-implant, which required an increased electrical stimulation. The third patient reached the identification category probably due to auditory dyssynchrony, as an atypical consequence of the syndrome.

Reactive oxygen species in human inner ear perilymph

Conclusions: The results reported here provide the first evidence of the production of superoxide, a biologically relevant reactive oxygen species (ROS), in human inner ear perilymph (hIP) in pathological conditions, by the activity of the xanthine dehydrogenase/xanthine oxidase (XA/XO) enzyme system. Objective: To investigate the presence of ROS in hIP. Methods: Since damage and apoptosis of inner ear hair cells may occur as a result of ROS-mediated injury, we investigated the presence and production of ROS in 105 hIP samples; 98 collected from patients affected by profound sensorineural hearing loss, during surgery for cochlear implantation, and 7 controls, collected from patients affected by otosclerosis, in case of spontaneous leakage after stapedotomy. ROS production was investigated by spectrophotometric analysis and polyacrylamide gel electrophoresis (SDS-PAGE). Results: In hIP samples tested by cytochrome c reduction kinetics, the average superoxide production was 27.34 μmoles per mg of total protein, against 0.36 in controls. Some of these hIP samples, analyzed by cytochrome c reduction kinetics in the presence of xanthine, were found to be positive for ROS-producing XA/XO enzyme. These results were supported by SDS-PAGE analysis.

High frequency hearing loss in the elderly: effect of age and noise exposure in an Italian group

OBJECTIVE To describe the effect of age and noise on high frequency hearing thresholds in an Italian population aged 70 years and older, in order to investigate the interaction between presbycusis and noise exposure. METHODS We compared 460 subjects: 367 affected by presbycusis alone (204 women and 163 men) and 93 affected by presbycusis and noise exposure (eight women and 85 men). Pure tone average hearing thresholds, for each ear, were compared between groups, and between sexes and ages within groups. RESULTS A slight threshold difference was found between the two groups at 4 kHz. After adjusting for age and gender, this difference was found to be related only to differing patient age. Mens and womens thresholds differed significantly in both groups, especially at high frequencies, at which threshold deterioration was worse in men than women. CONCLUSION The threshold differences between patients with presbycusis with and without noise exposure were limited. Larger studies are needed to assess the relative effects of ageing and noise exposure on hearing thresholds.