Controversial Role of Folic Acid on Diabetic Auditory Neuropathy.

OBJECTIVE: Diabetic auditory neuropathy (DAN) is a common complication of diabetes that seriously affects the quality of life in patients. In this study, we investigate the role of folic acid in the treatment of DAN in an experimental rat model. METHODS: Thirty-two Sprague-Dawley rats were equally divided into four groups: group 1, normal; group 2, diabetic rats; and groups 3 and 4, diabetic rats treated with folic acid (40 and 80 mg/kg, respectively). We used some tools to investigate the therapeutic effect of folic acid on DAN. We evaluated auditory brain stem response (ABR), estimated the volume and number of spiral ganglion and the volume of stria vascularis and spiral ligament by the stereological method, and measured the blood levels of homocysteine (HCY), malondialdehyde (MDA), and superoxide dismutase (SOD). RESULTS: Our study showed that folic acid treatment was not significantly effective in improving structural and functional disorders in DAN, even though its effectiveness in reducing HCY (P < 0.001) and MDA (P < 0.05) as oxidative biomarkers was significant. CONCLUSION: Folic acid is not effective in relieving morphological and functional disorders in DAN.

Association between swallowing disorders and cognitive disorders in adults: a systematic review and meta-analysis.

There is no consensus regarding the association between dysphagia and cognition. The aim of this study was to quantitatively and qualitatively analyze the available evidence on the direction and strength of the association between dysphagia and cognition. PubMed, Scopus, Embase, and Web of Science were searched for studies about the association between dysphagia and cognition. A random effects model was used to determine weighted odds ratios and 95% confidence intervals. Sensitivity analysis was performed to determine the impact of each individual study on the pooled results. A total of 1427 participants showed that some cognitive disorders were significantly associated with dysphagia (odds ratio = 3.23, 95% confidence interval: 2.33-4.48). The association between cognition and swallowing disorders suggests that multiple neuroanatomical systems are involved in these two functions.

Cochlear implant outcomes in children with attention-deficit/hyperactivity disorder: Comparison with controls.

OBJECTIVES: The coincidence of attention-deficit/hyperactivity disorder (ADHD) and hearing loss in the children has adverse effects in speech, cognition, communication and motor development. This can influence cochlear implant (CI) outcomes negatively. The aim of this study was to compare auditory, language, speech, cognition, communication and motor outcomes between CI children with versus without ADHD. METHODS: Nineteen CI children with ADHD and twenty-three age and gender matched children without ADHD at the Shiraz CI center ranging in age from 37 to 60 months were participated in this cross-sectional study. The developmental quotient in auditory, receptive and expressive language, speech and cognition skills was evaluated through Newsha Developmental Scale. The Persian version of the Ages and Stages Questionnaire (ASQ) was used to assess children's developmental status in fine and gross movements, communication, problem solving, and personal-social domains. A comparison of the results between two groups was made by the Mann-Whitney test. RESULTS: CI children with ADHD had significantly lower Newsha developmental quotients in cases of auditory, receptive and expressive language, speech and cognition skills compared to the control group (P = 0.027 to <0.001). A significant difference was observed between children with and without ADHD in fine and gross movements, communication, problem solving, and personal-social domains of ASQ at 60 months (P = 0.029 to 0.003). CONCLUSION: Children with ADHD showed decreased ability in auditory, language, speech, cognition, motor and communication skills following CI compared to children without ADHD. It can guide clinician to provide these children with more specific rehabilitation program to improve their skills.

Enhancing Working Memory Capacity in Persian Cochlear Implanted Children: A Clinical Trial Study.

INTRODUCTION: Sensory deprivations such as hearing impairment that affect sensory input have a secondary impact on cognitive functions such as working memory (WM). WM capacity is an important cognitive component that processes language-related activities. Moreover, several studies have shown a deficit in WM in children with a cochlear implant (CI). We aimed to assess the performance of children with CIs in pre- and post-training sessions and compare their scores on a battery of WM tests to investigate the efficacy of a WM training program. MATERIALS AND METHODS: Twenty-five children aged 7-10 years with a CI participated in this study. To train their WM, a computer game was used. In order to examine auditory WM, a test battery including standardized digit span (forward and backward variations), non-word and sentence repetition (subtest of the Test of Language Development-Primary) were assessed in pre- and post-training test sessions at Shiraz Implant Center. RESULTS: There were statistically significant differences between pre- and post-training test scores on all subtests. Test score differences were statistically significant for forward digit span (P=0.003), backward digit span (P=0.001), non-word repetition (P=0.001), and sentence repetition tasks (P=0.003) before and after training sessions. CONCLUSION: Training may enhance WM capacity. With regards to the importance of WM in literacy and learning, it seems applying such intervention programs may be helpful in the rehabilitation of implanted children.

Effects of Hyperlipidemia on Noise Induced Hearing Loss (NIHL).

Likelihood of developing noise induced hearing loss (NIHL) is affected by some factors such as genes, nutrition and healthy hearing habits. We investigated this study to determine the effect of hyperlipidemia on NIHL. In a case-control study, 144 workers who exposed to continuous noise more than 85 dBA (88-89 dBA) from a textile factory in Tehran were examined. Serum Blood test results as index for dyslipidemi, were collected and audiometry tests were carried out to analyze the association of hyperlipidemian and NIHL. The mean ±SD of Cholesterol level for NIHL and control were 188.19 (28.46) and 159.00 (26.66) mg/dL respectively. Also the mean ±SD of Triglyceride level for NIHL and control were 203.75 (53.92) and 105.00 (30.50) mg/dL consecutively. After adjusting odds ratio (OR) for NIHL, only hypertriglyceridemia had association with NIHL. (aOR = 1.07; 95 % CI 1.04-1.10), and there wasn't any relation between hypercholestomia and NIHL (aOR = 1.02; 95 % CI 0.99-1.05). Workers with hypertriglyceridemia are at increased risk for NIHL. In factories with elevated noise levels, besides hearing conservation programs, attention to blood serum level of workers and healthy diet are proposed to help in preserving hearing threshold.

Distortion Product Otoacoustic Emission (DPOAE) as an Appropriate Tool in Assessment of Otoprotective Effects of Antioxidants in Noise-Induced Hearing Loss (NIHL).

Distortion product otoacoustic emission (DPOAE) appears to be an objective sensitive test of cochlear function. The aim of this study was to investigate whether DPOAE is an appropriate tool for assessment of minute changes in cochlea due to usage of antioxidant material. 48 workers exposed to continuous noise in a textile factory were randomly assigned into three groups: (1) The Control group (n = 16) received no antioxidant drugs, (2) The N-acetyl-cysteine (NAC) group (n = 16) received oral antioxidant NAC (1200 mg/day), (3) The Ginseng group (n = 16) received oral antioxidant Ginseng (200 mg/day). All three groups had a follow-up period of 2 weeks. The cochlear changes were assessed using DPOAE test before starting the daily work shift on first and 15th day. The associations between groups and DPOAE amplitudes after 2 weeks were analyzed using linear regression analysis. Four separate models were fitted by side of ears and frequency. All models were adjusted for baseline amplitude. Reduced (better) amplitude at DPOAE test was found for NAC and Ginseng groups at high frequencies (4 and 6 kHz) in both ears after 2 weeks compared to control group. Moreover, NAC group showed better DPOAE amplitude than Ginseng group. In conclusion, DPOAE seems to be an appropriate tool in assessing minute changes in the cochlea after antioxidant drugs administration.

Comparison of the effects of N-acetyl-cysteine and ginseng in prevention of noise induced hearing loss in male textile workers.

Previous studies revealed the role of antioxidant agents in prevention of noise induced hearing loss (NIHL). The aim of this study was to compare the protective effect of N-acetyl-cysteine (NAC) and ginseng on protection of NIHL in textile workers exposed to continuous noise in daily working. In this study, 48 participants were randomly allocated to three groups; Group I received NAC 1200 mg/day, Group II received ginseng 200 mg/day, and Group III (control group) received no supplement. Pure tone audiometry and high frequency audiometry were performed preshift before and after 14 days (on day 15). Linear regression analysis results showed reduced noise-induced temporary threshold shift (TTS) for NAC and ginseng groups at 4, 6 and 16 kHz (P < 0.001) in both ears. Furthermore, the protective effects were more prominent in NAC than ginseng. Our results show that NAC and ginseng can reduce noise induced TTS in workers exposed to occupational noise. Further studies are needed to prove antioxidants benefits in hearing conservation programs.

A survey of relationship between rheumatoid arthritis and hearing disorders.

RA (rheumatoid arthritis) is a chronic multisystem disease with a variety of systemic manifestations. One of these manifestations, is hearing disorder, so study of the relation between RA and hearing disorders is seem important. This was a case-control study which has done from December 2004 to August 2006. This study compared 50 patients with RA, with age, sex and job-matched as control. Audiometric tests in different frequencies show that hearing threshold in high frequencies specially in 8000 Hz had a significant difference between two groups, also acoustic reflexes were absent in case groups and had significant difference between two groups too. The evaluation of sensory neural hearing loss showed that this hearing loss is sensory not neural. Based on this study, frequent evaluation of audiometric tests is recommended for controlling hearing disorders by therapeutic and rehabilitation procedures in RA patients.