Relationships of orexigenic and anorexigenic hormones with body fat distribution in patients with obstructive sleep apnea syndrome.

PURPOSE: We aimed to examine the relationships of disease activity and risk factors with serum levels of orexigenic and anorexigenic hormones in patients with obstructive sleep apnea syndrome (OSAS). METHODS: Fasting blood samples were taken for hormonal analysis of all participants, abdominal/neck bioimpedance measurements were recorded, and polysomnography (PSG) analyses were performed. According to the apnea-hypopnea index (AHI), 34 patients with newly diagnosed OSAS and 34 participants without OSAS were compared. RESULTS: The median body mass index (BMI) measured in the OSAS group was 30.39 kg/m2 and AHI was 18.95 and these values were 25.40 kg/m2 and 1.55 in the control group. There was a higher level of visceral adiposity and neuropeptide Y (NPY) in the moderate-to-severe OSAS group compared to the mild OSAS and control groups, and in the mild OSAS group compared to the control group (p = 0.001, p < 0.001). A positive correlation between the level of NPY and AHI and BMI (p < 0.001, p = 0.011), and a negative correlation between NPY levels and oxygen saturation (p = 0.001) was found. Oxygen saturation and desaturation rates were correlated with body fat percentage, body fat mass, abdominal adiposity, visceral adiposity, resting metabolic rate, and NPY levels. CONCLUSIONS: The visceral adiposity ratio and increase in NPY levels are important parameters that increase the severity of OSAS. Considering the negative effects of NPY on vascular endothelium, measurement of basal NPY level before PSG in patients with OSAS is considered a parameter related to disease severity.

The evaluation of serum brain-derived neurotrophic factor and neurofilament light chain levels in patients with obstructive sleep apnea syndrome.

OBJECTIVES: This study aimed to compare serum levels of brain-derived neurotrophic factor (BDNF) and neurofilament light (NfL) chain in normal individuals and patients with mild and moderate-severe obstructive sleep apnea syndrome (OSAS). METHODS: We enrolled 81 subjects referred to Otorhinolaryngology (Ear-Nose-Throat), Gazi University Faculty of Medicine, between 2017 and 2019. Based on the severity of OSAS, patients were divided into three groups: group 1 with mild OSAS (apnea-hypopnea index [AHI] 5-15; n = 26), group 2 with moderate-severe OSAS (AHI > 15; n = 32), and group 3 with normal individuals (AHI scores < 5; n = 23). RESULTS: Serum NfL and BDNF levels were evaluated together with the clinical data for all subjects. Significant differences were seen in the oxygen desaturation index (ODI), apnea index, hypopnea index, sleep efficiency, and NfL levels (P < .05) between the three groups. In the moderate-severe group, NfL levels showed a significant positive correlation with apnea index (P < .05, r = .389), hypopnea index (P < .05, r = .455), and ODI (P = .04; r = .362). CONCLUSIONS: Our findings clarify the pathophysiology of OSAS in cases of repetitive hypoxia and chronic neuronal damage. Based on our results, we recommend that in addition to BDNF, NfL should also be evaluated in different and larger patient cohorts.

The evaluation of serum tryptophan and kynurenine levels in patients with obstructive sleep apnea syndrome.

PURPOSE: The kynurenine (Kyn) pathway may play a role in certain physiological functions such as behavior, sleep, thermoregulation, and pregnancy. Tryptophan (Trp) is oxidized with tryptophan 2,3-dioxygenase and indolamine 2,3-dioxygenase (IDO). Under normal conditions, hepatic kynurenine is a transcription factor and IDO expression in healthy tissues is very low. The ratio of Kyn to Trp can be used as an indicator to assess IDO activity. This study aimed to determine the relationship between Kyn/Trp ratio and obstructive sleep apnea syndrome (OSAS) disease activity. METHODS: Study participants were categorized in 3 groups: Group 1 included patients with mild OSAS, Group 2, patients with moderate to severe OSAS, and Group 3, individuals considered normal to serve as controls. The demographic characteristics of the patients were recorded. Apnea-hypopnea index (AHI) and oxygen desaturation index (ODI) measurements were performed by diagnostic polysomnography (PSG). Trp and Kyn levels were determined by HPLC-UV method. RESULTS: Group 1 included 30 patients (18 men) with mild OSAS; Group 2 included 42 patients (31 men) with moderate to severe OSAS; and Group 3 included 25 controls (13 men). While there was no statistically significant difference between the levels of tryptophan and kynurenine in the groups, a significant difference was found between the Kyn/Trp ratios. A significant correlation was observed in individuals with a body mass index less than 25 with the Kyn/Trp ratio. In individuals with mild OSAS, a significant correlation was observed between ODI and BMI. In individuals with moderate to severe OSAS, there was a significant correlation between ODI, AHI, and BMI. CONCLUSION: In this study, there was no relationship between OSAS disease severity and IDO activity as assessed by immunoreactivity via the Kyn/Trp pathway.

Canal wall down versus canal wall up surgeries in the treatment of middle ear cholesteatoma

Background/aim: To compare outcomes of canal wall up (CWU) and canal wall down (CWD) techniques in the treatment of middle ear cholesteatoma. Materials and methods: Medical records of 76 patients who had a primary surgery due to middle ear cholesteatoma between July 2015 and November 2017 were reviewed retrospectively. Hearing thresholds, speech discrimination scores (SDS), recurrences, and revision surgeries of CWU and CWD surgeries were compared. Results: Of 76 cholesteatoma cases, 40 (52.6%) had a CWU and 36 (47.4%) had a CWD operation. Postoperatively, the mean air conduction thresholds were significantly better in CWU compared to CWD surgeries (P = 0.016). The presence of the stapes and the type of reconstruction material used did not have a significant effect on auditory success rates (P = 0.342 and P = 0.905, respectively). Auditory success was affected by the status of the middle ear mucosa as well. The recurrence and revision rates did not differ between the surgical techniques (P > 0.05). Conclusion: Status of the middle ear mucosa and external auditory canal are important factors affecting the outcomes in cholesteatoma. Instead of a CWD surgery, a CWU surgery seems applicable in cases of cholesteatoma when the bone in the external auditory canal is not eroded by the disease.

The effect of obstructive sleep apnea syndrome on the central auditory system

Background/aim: Obstructive sleep apnea syndrome (OSAS) is a disease characterized by repeated hypoxia attacks during sleep. The effect of hypoxia on the central nervous system is a well-known entity. In this study we aimed to investigate the effect of OSAS on the central auditory system. Materials and methods: Twenty-one OSAS patients diagnosed by polysomnography (PSG) and 10 control subjects were included in the study. After a thorough otorhinolaryngology examination, all subjects underwent pure tone audiometry (250 to 8000 Hz frequency). The subjects with normal otoscopic examination and hearing threshold were included in the study. All participants underwent speech discrimination analyses and auditory time processing and sequencing tests, i.e. frequency pattern test (FPT) and duration pattern test (DPT). Results: Although hearing was normal in the OSAS patients, significant loss was observed in the speech discrimination rates compared to the control group (P < 0.05). Significant disruption was also detected in the FPT and SPT in the OSAS patients (P < 0.05). Conclusion: Repeated hypoxic episodes in OSAS resulted in statistically significant impairments in the central auditory pathways, even if the hearing threshold was within normal limits.

Does nasal congestion have a role in decreased resistance to regular CPAP usage?

Nasal obstruction is known to cause resistance to continuous positive airway pressure (CPAP) therapy in obstructive sleep apnea syndrome (OSAS). In this paper, short- and long-term nasal congestion in OSAS patients receiving CPAP treatment were evaluated with acoustic rhinometry (AR). A total of 36 patients with moderate-to-severe OSAS, diagnosed with polysomnography were included in the study. Ten healthy subjects without OSAS constituted the control group. Pre-treatment nasal patency were measured with AR in all participants. 26 patients used the recommended CPAP treatment. Ten patients did not accept CPAP treatment. The AR test was repeated for all the subjects after 1 and 3 months except the 3rd month's measurements of the control group. There was no statistically significant difference between the initial minimum cross-sectional area (MCA) measurements of OSAS patients, using or not using CPAP, and the control group (P > 0.05). However, the first month MCA measurements of patients receiving CPAP were found to be significantly decreased compared with the initial values (P < 0.001). There was no significant change in the first and third months MCA values in the control group and patients who did not use CPAP (P > 0.05). No significant difference revealed in the 3rd month MCA measurements of the patients using CPAP compared with the initial values (P > 0.05). In this study, the increased nasal congestion, which is thought to be the cause of CPAP resistance, was objectively demonstrated in OSAS patients using CPAP. In addition, the nasal congestion developing at the first month was shown to disappear over time, supporting the opinion that patient compliance in CPAP treatment is expected to increase after regular device usage.

Evaluation of hearing functions in patients with euthyroid Hashimoto's thyroiditis.

Sensorineural hearing loss has been reported in various autoimmune diseases. The relationship between Hashimoto's thyroiditis (HT) and the auditory system has not been previously evaluated. In this study, we investigated the effect of euthyroid HT on the hearing ability of adult patients. The study included 30 patients with newly diagnosed euthyroid HT and 30 age- and gender-matched healthy controls. All subjects had a normal otoscopic examination and tympanometry, and they were negative for rheumatoid factor, antinuclear, anti-smooth muscle, antimitochondrial, antineutrophilcytoplasmic, and antigliadin antibodies. Pure tone audiometry exams at 250, 500, 1000, 2000, 4000, 6000, and 8000 Hertz (Hz) were performed in both groups. Thyroid peroxidase antibody and thyroglobulin antibody (anti-Tg) levels were higher in HT group while TSH, free T4, free T3, plasma electrolytes, glucose, lipid profile, vitamin B12, and blood pressure measurements were similar between the two groups. Higher audiometric thresholds and a higher prevalence of hearing loss at 250, 500, and 6000 Hz were detected in the HT patients than in the healthy controls (P < 0.05). Hearing levels at 250 and 500 Hz correlated positively with anti-Tg levels (ρ = 0.650, P = 0.002; ρ = 0.719, P < 0.001, respectively), and this association remained significant in linear regression analysis. Anti-Tg-positive HT patients had higher hearing thresholds at 250 and 500 Hz than anti-Tg-negative HT patients. Hearing thresholds were similar between anti-Tg-negative HT patients and the control subjects. This study demonstrated that hearing functions are impaired in HT patients. Thyroid autoimmunity seems to have an important impact on a decreased hearing ability, particularly at lower frequencies, in this population of patients.

Increased carotid artery intima-media thickness in patients with tympanosclerosis: Common risk factors with atherosclerosis?

We investigated the relationship between tympanosclerosis, known atherosclerotic risk factors, and the intima-media thickness of bilateral carotid arteries using ultrasonography. A total of 122 patients admitted to our clinic with chronic otitis media between 2005 and 2010 were included in the study. The study group consisted of 61 patients with tympanosclerosis; the control group comprised 61 patients without tympanosclerosis. Internal carotid artery intima-media thickness (CAIMT), total cholesterol, triglyceride, low- and high-density lipoprotein cholesterol, C-reactive protein, and homocysteine levels were measured in all patients. Homocysteine, low-density lipoprotein, total cholesterol, and triglyceride levels in the study group were higher compared with those of the control group (p < 0.05). Right and left CAIMT was greater in the study group versus the control group (p ≤ 0.001). In conclusion, atherosclerosis and tympanosclerosis were associated with identical risk factors; in the tympanosclerosis group, CAIMT was increased significantly.

Vestibular functions were found to be impaired in patients with moderate-to-severe obstructive sleep apnea.

OBJECTIVES/HYPOTHESIS: Obstructive sleep apnea (OSA) and balance disorders are common chronic diseases seen in the general population. The aim of this study was to evaluate vestibular functions in individuals with OSA. STUDY DESIGN: Cross-sectional clinical study. METHODS: Patients who were referred to the sleep clinic in our hospital were classified into two groups according to a polysomnographic test: a moderate-to-severe OSA group and a mild OSA group. A vestibular system assessment of all patients was performed subjectively with the Dizziness Handicap Inventory (DHI) survey and objectively with videonystagmography. RESULTS: The current investigation produced four major findings: 1) Apnea-hypopnea index was significantly correlated with age and body mass index, whereas it was not correlated with Epworth Sleepiness Scale scores. 2) There was a significant difference in study groups in terms DHI scores, particularly in the physical subgroup. Moderate-to-severe OSA patients had higher scores in the physical subgroup of DHI. 3) Nystagmus and canal paresis rates were significantly higher in the moderate-to-severe OSA group when compared to the mild OSA group. 4) Results of the Romberg test, tandem Romberg test, cerebellar examinations, and positional tests were normal in both. CONCLUSIONS: Abnormal vestibular responses are common in individuals suffering from severe OSA, and dizziness has negative effects on the quality of life in these individuals. LEVEL OF EVIDENCE: 4

Are systemic voriconazole and caspofungin ototoxic? An experimental study with rats.

OBJECTIVES: To determine whether systemic administration of voriconazole and caspofungin causes ototoxicity. METHODS: This study was conducted on 32 healthy male Wistar albino rats. The baseline auditory brainstem response (ABR) thresholds of all animals were obtained under general anesthesia. Then, the rats were randomly divided into 4 groups (groups I-IV), each group consisting of 8 rats. Rats in group I were injected intraperitoneally with voriconazole 10 mg/kg/day for 7 days, and the rats in the group II were injected intraperitoneally with caspofungin 5 mg/kg/day for 7 days. Group III received 120 mg/kg/day gentamicin for 7 days. Group IV received saline for 7 days. The animals were then observed for 7 days, and on 14th day of the trial, posttreatment ABRs of both ears were recorded. RESULTS: We did not find any significant differences between pretreatment and posttreatment median ABR thresholds in the voriconazole, caspofungin, or saline groups. In the gentamicin group, there was a statistically significant difference between pretreatment and posttreatment ABR thresholds. CONCLUSION: Caspofungin and voriconazole did not change ABR thresholds in speech frequencies after a 7-day-period of their administration. We believe that further animal studies must be performed after administration of these agents for a longer time period, and these findings must be consolidated with histopathological investigations.

Changes in the ocular and nasal cultures in patients who had undergone septoplasty.

OBJECTIVE: The aim of the study was to evaluate the microbiologic changes that occurred in the nasal and ocular mucosa before and after surgery in patients who had undergone septoplasty. DESIGN SETTING: Fifty-five patients who applied to our clinic with septal deviation were included in the study. METHODS: Before and after the operation, samples were taken from the ocular and inner nasal mucosa for cultures and direct microscopic evaluation and the microbiologic changes were compared. MAIN OUTCOME MEASURES: The results of ocular preoperative cultures were different from the results of postoperative cultures. RESULTS: The most frequent microorganisms in all pre- and postoperative ocular and nasal cultures were similar; coagulase-negative Staphylococcus, Staphylococcus aureus, and Diphtheroid spp were dominant. Following septoplasty, the rate of determining microorganisms in the eye in both microscopic evaluation and cultures had increased. In the postoperative period, the rate of growing S. aureus increased in ocular cultures (p < .01) while remaining the same in nasal cultures. CONCLUSIONS: These results suggest that ocular flora can indeed change following septoplasty; however, the risk of ocular infection is not increased. This is the first study to investigate the risk of ocular infection in addition to local nasal infection after septoplasty.

An alternative model for stapedectomy training in residency program: sheep cadaver ear.

To determine the usefulness of sheep cadaver ear as a complementary model for training of stapedectomy at residency programs, 2 of our 4 year residents were included in the study and each operated 20 sheep ears. All routine steps of stapedectomy operation were performed, and their success and complication scores were recorded. Performance of residents for stapedectomy and teflon piston placement in sheep ears were evaluated by the authors. Success of both residents improved progressively. Success and complications were impressively better in the second 10 ears than the initial 10 for each resident. Both residents had better outcomes in last 10 ears. Sheep cadaver ear is an excellent model for stapedectomy training in residency and helps to improve surgical skills. We offer sheep cadaver ear training model especially in the countries where obtaining human cadaver temporal bone is difficult.