The effectiveness of oropharyngeal exercises compared to inspiratory muscle training in obstructive sleep apnea: A randomized controlled trial.

BACKGROUND: Inspiratory muscle training (IMT) and oropharyngeal exercises (OE) have different advantages and disadvantages and a comparison of these modalities has been recommended. The aim of this study was to compare the effects of IMT and OE on important outcomes for patients with OSAS. METHODS: This was a randomized controlled clinical trial. Forty-one clinically stable OSAS patients not receiving CPAP therapy were randomly divided into three groups. Patients in the IMT group (n = 15) trained with a threshold loading device 7 days/week for 12 weeks. Patients in the OE group (n = 14) practiced exercises 5 days/week for 12 weeks. Twelve patients served as control group. Apnea-hypopnea index (AHI), respiratory muscle strength, snoring severity and frequency (Berlin Questionnaire), daytime sleepiness (Epworth Sleepiness Scale; ESS), sleep quality (Pittsburg Sleep Quality Index; PSQI), impact of sleepiness on daily life (Functional Outcomes of Sleep Questionnaire; FOSQ), and fatigue severity (Fatigue Severity Scale; FSS) were evaluated before and after the interventions. RESULTS: AHI and sleep efficiency did not change significantly in any of the groups. Significant decreases in snoring severity and frequency, FSS and PSQI total scores were found in the IMT and OE groups after the treatments (p < 0.05). There was a significant reduction in neck and waist circumference and significant improvement in respiratory muscle strength (MIP and MEP) in IMT group compared to control group (p < 0.05). The%MEPpred value and FOSQ total score significantly increased and ESS score reduced after the treatment in OE group compared to control group (p < 0.05). CONCLUSIONS: Our results indicate that both OE and IMT rehabilitation interventions are applicable in rehabilitation programs for OSAS patients who do not accept CPAP therapy. Our findings could lead to increase these methods' use among rehabilitation professionals and decrease in cost of CPAP treatment in OSAS.

The effect of hypoxia on hearing function

Background/aim: This study was conducted to determine the critical partial oxygen pressure (pO2) value that would impair hearing function by evaluating the effects of hypoxia on hearing function in subjects diagnosed with chronic obstructive pulmonary disease (CPOD). Materials and methods: The study included 25 male and 5 female patients referred to our clinic who were diagnosed with COPD, according to spirometry and PaO2 values, and who did not show pathology upon autoscopic examination. The control group consisted of 14 female and 16 male patients who had no lung disease and were in the same age range as the COPD group. Results: A statistically significant difference was found between the two groups for distortion-product otoacoustic emission (DPOAE) (P < 0.001). The COPD group was divided into two groups according to pO2 levels (pO2 ≤ 70 and pO2 > 70) in order to find a critical pO2 level which might cause significant change at a certain audiological extent. Conclusion: Hypoxia causes long-term decline in hearing thresholds, deterioration of DPOAE results, and prolongation of I­V interpeak latency in auditory brainstem response. However, the critical oxygen level that disrupts hearing function could not be determined.

Absenteeism and Delay to Work Due to Sleep Disorders in the Turkish Adult Population: A Questionnaire-Based National Survey.

Sleep problems may have negative effects on work-life balance, overall health, and safety. We aimed to investigate the association between sleep disorders and absenteeism and delay to work (being late or tardy) among the working adult population. The study was conducted by using data from a large survey of working adults who participated in the Turkish Adult Population Epidemiology of Sleep Study (TAPES) managed by Turkish Sleep Medicine Society (TSMS). Secondary analyses was employed to examine absenteeism and delay to work and their associations with sleep problems, including sleepiness by Epworth Sleepiness Scale (ESS), parasomnias, sleep apnea (by Berlin Questionnaire), sleep quality (by Pittsburgh Sleep Quality Index), and restless leg. History of any absenteeism and delay to work was observed in 276 (18%) and 443 (29%) out of 1,533 working adults, respectively. In the multivariate analyses, absenteeism was associated with younger age, female gender and poor sleep quality, while delay to work was associated with younger age, poor sleep quality, parasomnia, and sleepiness. In the presence of absenteeism and delay to work, sleep disorders including sleepiness, poor sleep quality, and parasomnia should be considered. Such evaluation may improve worker well-being and provide some additional benefits in terms of increasing productivity and lowering work-related costs.

Evaluation of sleep quality in patients with ankylosing spondylitis and efficacy of anti-TNF-α therapy on sleep problems: A polisomnographic study.

INTRODUCTION: This study was conducted to investigate the relationship between sleep quality (SQ) and disease activity (DA) in patients with ankylosing spondylitis (AS) and to evaluate the response to anti-tumor necrosis factor α (anti-TNF-α) therapy on sleep disorders. MATERIALS AND METHODS: A total of 34 patients who met the modified New York classification criteria for AS were included in this prospective study. Patients were divided into two groups as follows: Group I (n = 15) with high DA and receiving anti-TNF-α therapy, and Group II (n = 19) in remission. DA was assessed by the Bath AS Disease Activity Index. Pittsburgh Sleep Quality Index (PSQI) and polysomnography (PSG) were used to determine disorders and patterns of sleep, respectively, in both groups at baseline as well as at the third month of anti-TNF-α therapy in Group I. RESULTS: Baseline evaluation revealed impaired SQ in 57.9% of all patients. PSG demonstrated obstructive sleep apnea syndrome, snoring and periodic leg movements in 73.7%, 74.4% and 26.3% of patients, respectively. Prior to anti-TNF-α therapy, PSQI and snoring score were significantly higher in Group I (P = 0.0001, P = 0.012, respectively). Although there was a significant reduction in PSQI scores in Group I (P = 0.005) at the third month of anti-TNF-α therapy, no change was observed in PSG parameters (P > 0.05). CONCLUSION: Sleep disorders increase in AS, particularly in patients with high DA. Anti-TNF-α therapy has improved SQ without any improvement in PSG. Therefore, it may be concluded that PSG parameters might be more associated with disease pathogenesis rather than DA in patients with AS.

Alteration of serum levels of inflammatory cytokines and polysomnographic indices after uvulopalatal flap surgery in obstructive sleep apnea.

The aim of the current study was to compare the changes in polysomnographic indices and serum levels of C-reactive protein (CRP), cystatin C, tumor necrosis factor-α (TNF-α), and intercellular adhesion molecule-1 (ICAM-1) in patients with obstructive sleep apnea (OSA) who were treated surgically via a uvulopalatal flap (UPF) technique. Twenty-five patients (14 men, 11 women), average age 46.2 ± 9.3 years, who underwent UPF surgery were included in this study. Serum biochemical analyses and polysomnographic examinations were performed before and 6 months after the surgery. Pre- and postoperative values of apnea hypopnea index (AHI), oxygen desaturation index (ODI), and minimum oxygen concentrations, as well as serum levels of CRP, cystatin C, TNF-α, and ICAM-1 were compared. Comparison of variables before and after UPF surgery demonstrated that AHI (p = 0.001), ODI (p < 0.001) and oxygen saturation (p < 0.001) were significantly improved. In addition, serum levels of CRP (p = 0.036), cystatin C (p = 0.005), TNF-α (p < 0.001), and ICAM-1 (p < 0.001) were significantly reduced 6 months after surgery. Our results suggest that UPF is an effective surgical method that alleviates the severity of OSA. Moreover, it may have the potential to prevent the development of atherosclerosis by attenuating the inflammatory process induced by activation of inflammatory mediators such as CRP, TNF-α, ICAM-1, and cystatin C.

The evaluation of sleep quality and response to anti-tumor necrosis factor α therapy in rheumatoid arthritis patients.

Poor sleep quality (SQ) is increasingly recognized as giving rise to decreased quality of life, and raising pain perception. Our aim is to evaluate the SQ in rheumatoid arthritis (RA) patients treated with anti-tumor necrosis factor alpha (anti-TNF-α) therapy. This was a prospective observational and open-label study of RA patients. A total of 35 patients with RA were enrolled in this study. Of the 35 patients, 22 had high disease activity (DA), and 13 were in remission. High DA group was initiated an anti TNF-α therapy. Clinical and objective parameters of SQ were assessed by using the Pittsburgh Sleep Quality Index (PSQI) and polysomnography (PSG). The total PSQI score and the frequency of poor SQ were high in 60 % of the RA patients. The median PSQI score was significantly higher in the high DA group than in the remission group (P = 0.026). Following an anti-TNF-α therapy initiation, significant improvements were observed in the high DA group by PSQI test (P = 0.012). However, no statistically significant difference was found by PSG (P > 0.05). Although an improvement in DA with anti-TNF-alpha therapy did not provide an amelioration in laboratory parameters, we found a significant improvement in SQ by subjective PSQI test. These findings may support that sleep disorders in RA are likely to be associated with a complex pathophysiology.

YKL-40: may be use as a new inflammatory biomarker in obstructive sleep apnea syndrome?

INTRODUCTION: YKL-40 [chitinase-3 like-1 (CHI3L1)] is a glycoprotein, has been implicated in inflammation, endothelial dysfunction, tissue remodelling and it is accepted as a noninvasive prognostic biomarker for inflammation. In this study, we aimed to underline usability of serum YKL-40 as an inflammatory biomarker in patients with obstructive sleep apnea syndrome (OSAS). PATIENTS AND METHODS: Two groups OSAS patients [Group I: Mild-moderate OSAS, n:43; median apnea-hypopnea index: AHI, /hour:18], Group II: Severe OSAS, n: 25; AHI:41.6] and healthy control group [n:25, AHI: 3.6] were included in the study. Serum YKL-40 level was tested in serum samples taken after polysomnography in OSAS patients and control group. In addition, the association of serum YKL-40 level with age, body mass index and polysomnografic parameters were analyzed in the OSAS patient groups. RESULTS: Median serum YKL-40 level was 20.30 ng/mL (range 8.01-73 ng/mL) in mild-moderate OSAS patients, and 22.58 ng/mL (9.17-99 ng/mL in severe OSAS patients, 18 ng/mL (range 7.36-88 ng/mL) in control group (p< 0.05). Serum YKL-40 level was found to be correlated with AHI in patient with mild-moderate OSAS patients (p< 0.05) and serum YKL-40 level was found to be correlated with age, total hypopnea time (minutes) in severe OSAS patients (p< 0.05). There was no relationship serum YKL-40 level with other studied variables (p> 0.05). CONCLUSION: At the end of this study, we found that serum YKL-40 level increase with severity of OSAS. The findings suggest that YKL-40 may be a useful biomarker for inflammation in patients with OSAS.

Does AHI Value Enough for Evaluating the Obstructive Sleep Apnea Severity?

Obstructive sleep apnea/hypopnea syndrome (OSAHS) is an important and more common public health problem with increasing incidence. Polysomonography (PSG) is the gold standard test in OSAHS diagnosis. Apnea-hypopnea index (AHI) is the main parameter of PSG, which is correlated with OSAHS severity. The main complaint of OSAHS patients is daytime sleepiness and the Epworth Sleepiness Scale (ESS) used for evaluation of disease severity. The correlation of AHI with daytime sleepiness and ESS is well known. But there are many patients, which have uncorrelated daytime sleepiness with AHI. This data calls this hypothesis; Are there any other parameters which may affect daytime sleepiness. 648 patients with complaining of snoring and apnea were evaluated by polysomnography and anthropometric measurements. The cut-off value of ESS was accepted 10 as an indicator of severe daytime sleepiness. Patients were divided to groups with the aim of homogenization, according to AHI values. The patients with similar AHI values were analyzed according to their ESS scores. BMI and neck circumference were elevated in daytime sleepiness patients. The nocturnal hypoxemia markers; apnea number/index, maximum duration of apnea, at least SO2 concentration, duration of SO2 less than 90 % were much effected in the group of daytime sleepiness. Beside the fact that our research, AHI is not enough for predicting the daytime sleepiness; anthropometric measurements and the nocturnal hypoxemia markers should be evaluated.

The effect of adding gender item to Berlin Questionnaire in determining obstructive sleep apnea in sleep clinics.

BACKGROUND AND AIM: We aimed to validate the Turkish version of Berlin Questionnaire (BQ) and developped a BQ-gender (BQ-G) form by adding gender component. We aimed to compare the two forms in defining patients with moderate to severe obstructive sleep apnea (OSA) in sleep clinics. METHODS: Four hundred and eighty five consecutive patients, refered to our sleep clinic for snoring, witnessed apnea and/or excessive daytime sleepiness were enrolled to the study. All patients underwent in-laboratory polysomnography (PSG). Patients with sleep efficiency less than 40% and total sleep time less than 4 hours, chronic anxiolitic/sedative drug usage, respiratory tract infection within past two weeks were excluded from the study. All the patients fulfilled BQ. The test and retest for BQ were applied in 15-day interval in 30 patients. RESULTS: Totally 433 patients were enrolled to the study (285 male, 148 female). The mean age of the patients was 47,5 ± 10.5 (21-79). 180 patients (41.6%) had apnea-hypopnea index (AHI) ≤ 15, while 253 patients (58,4%) had AHI > 15. The κ value was 48-94 and the the truth value was 69-94% for the test-retest procedure. Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and area under the curve AUC were 84.2%, 31.7%, 48.7%, 63.4%, and 0.579 in order for BQ and 79.9 %, 51.7%, 63.2% , 69.6%, and 0.652 for BQ-G. CONCLUSION: The results showed that BQ-G is relatively better than BQ in determining moderate to severe OSA in sleep clinics where most of the patients are sleep apneic but both of the tests were found to have insufficient validities in defining moderate to severe OSA in sleep clinics.

Prevalence of insomnia and its clinical correlates in a general population in Turkey.

AIM: The prevalence of insomnia is influenced by environmental factors. This study aimed to investigate the prevalence of insomnia and its sociodemographic and clinical correlates in a general population-based survey in Turkey. METHODS: This population-based study included 4758 subjects among 5021 who participated in the Turkish Adult Population Epidemiology of Sleep Disorders study. Questionnaire items evaluating insomnia were adapted from the International Classification of Sleep Disorders II and the DSM-IV-TR. Subjects with restless legs syndrome were excluded. RESULTS: Insomnia was found to be associated with older age (18-24 years, 9.8%; 25-44 years, 11.7%; 45-64 years, 13.8%; 65 years or older, 13.9%), lower income level (<500 USD, 16.5%), time spent watching TV (6-8 h or more, 18.4%), tea consumption in the evening (≥6 glasses, 14.5%) and smoking status (current and ex-smoker, both 14.2%) in multiple logistic regression analysis. In respect to other medical disorders, insomnia was significantly associated with the presence of hypertension, diabetes and heart diseases after the adjustment for relevant risk factors for each disease, across all age and sex groups. CONCLUSIONS: Insomnia is a major health problem in our population, affecting subjects in the working age group and those of lower socioeconomic status. It should especially be screened in patients with chronic diseases. A relatively low proportion of insomnia diagnosed as a sleep disorder suggests that this condition and its clinical correlates are possibly under-recognized.

Association of obstructive sleep apnea with homocystein, nitric oxide and total antioxidant capacity levels in patients with or without coronary artery disease.

INTRODUCTION: Obstructive sleep apnea (OSA) is associated with cardiovascular morbidity and mortality. Deficiency of nitric oxide (NO) and plasma levels of homocystein have been implicated in the pathogenesis of cardiovascular disease. OSA results in oxygen desaturation and arousal from sleep. Free oxygen radicals can be produced by hypoxia-reoxygenation. To test for the hypothesis that OSA is associated with cardiovascular morbidity, we investigated levels of homocystein, NO and total antioxidant capacity in OSA patients with and without coronary artery disease (CAD) in comparison with normal subjects and patients with CAD without OSA. MATERIALS AND METHODS: Polysomnography was performed in 27 patients who had a myocardial infarction and in 25 patients without evidence of CAD. Patients were grouped according their polysomnography results as OSA with CAD (group 1), OSA without CAD (group 2), CAD (group 3), and normal (group 4) . Levels of homocystein, NO and total antioxidant capacity were determined after an overnight fasting. Data were analysed with parametric and non parametric statistical tests. RESULTS: According to apnea-hypopnea index (AHI) 44.4% of CAD patients were OSA. After polysomnographic evaluation, the patients were re-distributed as follows: OSA with CAD (n= 12), OSA without CAD (n= 14), CAD (n= 15), and normal (n= 11). Homocystein levels were higher in 3 groups compared to controls. AHI, MDI and desaturation time was higher in three -vessel disease compared to one and two- vessel diseases (p< 0.05). NO levels were correlated with the period of oxygen desaturation (r: -0.45, p= 0.031). The antioxidant capacity did not differ between OSA and healthy groups. CONCLUSION: OSA is frequent in CAD. AHI, MDI and desaturation time are higher in patients with severe CAD. It is important to evaluate OSA patients for CAD.

Clinical update on pulmonary embolism.

Pulmonary embolism (PE) is a major cause of cardiovascular mortality and financial burden that affects the community. The diagnosis of PE can be difficult because of the nonspecific symptoms, which include cough, dyspnea, hemoptysis and pleuritic chest pain. Hereditary and acquired risk factors are associated with PE. Incidence of PE is increasing, associated with the development in the diagnostic methods. Evidence-based algorithms can help clinicians diagnose PE. Serum D-dimer level, computed tomography pulmonary angiogram (CTPA), ventilation-perfusion scintigraphy or echocardiography help to establish clinical probability and the severity of PE. Anticoagulation is the standard treatment for PE. However, thrombolytic treatment is a significant alternative in high risk of PE as it provides rapid clot resolution. This article reviews the risk factors, diagnostic algorithms, and methods of treatment in PE in the light of current information.

Long-term effects of PAP on ocular surface in obstructive sleep apnea syndrome.

OBJECTIVE: To assess the long-term effects of positive airway pressure (PAP) therapy on the ocular surface and eyelid in patients with obstructive sleep apnea hypopnea syndrome (OSAHS). DESIGN: Single-centred, prospective, and double-blinded study. PARTICIPANTS: Fifty-one patients with OSAHS. METHODS: Fifty-one patients with OSAHS were treated with PAP for a period of 18 months. The pre- and post-PAP values for eye examination scores (presence of floppy eyelid syndrome [FES], results of the Ocular Surface Disease Index [OSDI] questionnaire, Schirmer I test, tear film break-up time [TBUT] values, and corneal staining stages) were compared. RESULTS: Based on the apnea-hypopnea index, 17 patients were followed with moderate and 34 patients were followed with severe OSAHS. The presence of FES before and after PAP was 56.9% and 74.5% (p < 0.01). FES stage was determined as 1.41 ± 0.98 before PAP and 0.78 ± 0.78 after PAP (p < 0.01). Pre-PAP and post-PAP OSDI results were 47.79 ± 21.04 and 42.17 ± 19.97, respectively (p < 0.01). Schirmer values before and after PAP were 7.23 ± 1.95 and 8.49 ± 1.79 mm, respectively (p < 0.01). TBUT values before and after PAP were 7.11 ± 1.82 and 8.68 ± 1.76 seconds, respectively (p < 0.01). Scores of the corneal staining stages before and after PAP were 1.05 ± 0.75 and 0.68 ± 0.54, respectively (p < 0.01). CONCLUSIONS: OSAHS is associated with low Schirmer and TBUT values, and high scores in OSDI questionnaire, and high corneal staining stage. An appropriate PAP therapy helps to relieve both the systemic findings and the ocular surface problems most likely by providing a return to normal sleep patterns. We believe that long-term (at least 1 year) use of PAP improves the clinical picture of FES and can overcome the problem of ocular irritation that is encountered in the early stage of PAP.

The utility of neck/thyromental ratio in defining low-risk patients with obstructive sleep apnea in sleep clinics.

We aimed to evaluate the importance of neck/thyromental distance in the diagnosis of moderate to severe obstructive sleep apnea (OSA) in sleep clinics. 185 patients (122 males, 63 females) referred to our sleep clinic with OSA symptoms were enrolled to the study. The patients had level-1 polysomnography (PSG). The neck circumference (N), thyromental distance (T), and STOP test were recorded in all patients. Using an obstructive AHI > 15 event/h on PSG as the cut-off, the best N/T ratio to find patients with OSA was calculated with the receiver operator curve analyses. The best cut-off for N/T was chosen as 4.6. We used Modified STOP test: STO-NT test in which P (for hypertension item) was replaced with N/T ratio. N/T ratio >4.6 was scored as "positive". Two positives out of four questions in STO-NT were scored as high risk for OSA. The OSA prevalence was 60 % for AHI > 15. The mean ratio of N/T was significantly different between groups with AHI > 15 and AHI ≤ 15. N and N/T ratio were moderately correlated with AHI. Sensitivity, specificity, negative predictive value, positive predictive value, and negative likelihood ratio of STOP test for AHI > 15 were 88.5, 28.4, 61.8, 65.4 % and 0.40, whereas 97.3, 23, 85, 65.9 % and 0.12 for STO-NT test, respectively. STO-NT test seems better than STOP test in determining patients who do not likely to have moderate to severe OSA in sleep clinics so can be preferred to decide on therapies other than CPAP in a short time.

The relationship between CPAP usage and corneal thickness.

The purpose of this study was to determine whether there is a correlation between CPAP usage and corneal thickness in patients with sleep disordered breathing. Full-night polysomnography (PSG) recordings were collected. Ten patients had undergone PSG recordings with continuous positive airway pressure (CPAP), and seven patients had undergone PSG recordings without CPAP. We measured corneal thickness by ultrasonic pachymeter before sleep and ten minutes after waking. We also measured visual acuity with a routine ophthalmologic eye chart before and after sleep. We asked patients to fill out a post-sleep questionnaire to get their subjective opinions. In the without-CPAP group, corneal thickness increased significantly during sleep in both eyes (left, p = 0.0025; right, p<0.0001). In the with-CPAP group, corneal thickness did not increase significantly (p>0.05 for both left and right cornea). There was no significant difference in visual acuity tests (p>0.05 for both left and right eye) between the two groups. According to our results, there is a significant increase in corneal thickness in the without-CPAP group. Our data show that a low percentage of Rapid Eye Movement (REM) sleep may cause an increase in corneal thickness, which can indicate poor corneal oxygenation. In fact, many sleep-disordered breathing (SDB) patients have low REM. Since a contact lens may cause low corneal oxygenation, SDB patients with contact lenses should be monitored carefully for their corneal thickness.

Changes in serum levels of MDA and MMP-9 after UPF in patients with OSAS.

The aim of the study was to assess the markers of oxidant-antioxidant status in patients with obstructive sleep apnea syndrome (OSAS) who underwent uvulopalatal flap (UPF) surgery. Twenty-five patients who underwent UPF surgery participated in this study. Polysomnographic examinations were performed before and after the surgery to assess sleep apnea in all patients and to determine the success of the UPF surgery regarding the improvement in the apnea-hypopnea index (AHI). Descriptive factors (BMI, age, gender and neck thickness, etc.) of patients were recorded before operation. Blood samples were taken preoperatively, and repeated postoperatively at 6-month intervals to determine the changes in serum malondialdehyde (MDA) and matrix metalloproteinase-9 (MMP-9) levels. The mean age at surgery was 45.6 ± 9.9 years (range 25-63 years). There was a significant difference between preoperative and postoperative AHI, MDA and MMP-9 values (p < 0.05). There was no significant correlation between categorical variables. There was no correlation between postoperative ODI, MMP-9 and MDA. These results indicate that OSAS is associated with abnormal lipid peroxidation, which can be improved by UPF surgery. OSAS may increase risks of cardiovascular morbidity; however, UPF might be useful for decreasing these risks in patients with OSAS who are suitable candidates for UPF surgery.

Influence of gender on C-reactive protein, fibrinogen, and erythrocyte sedimentation rate in obstructive sleep apnea.

Inflammation is one of the pathophysiological pathways suggested for the development of cardiovascular disease in obstructive sleep apnea (OSA). The recurrent nocturnal episodes of hypoxia/reoxygenation observed in patients with OSA appear to be partly responsible for the systemic inflammatory response. The aim of this study was to investigate the role of inflammation by measuring the C-reactive protein (CRP) and fibrinogen levels, and erythrocyte sedimentation rate (ESR) in the OSA according to gender. This study included 139 apparently healthy subjects with newly diagnosed OSA and 27 control subjects who underwent overnight polysomnography and routine blood tests. Levels of inflammatory markers (CRP, fibrinogen, and ESR) were determined from the blood samples taken in the morning. The levels of CRP and fibrinogen were significantly higher in patients than in controls (p<0.0001 and p=0.001, respectively). Fibrinogen and ESR were significantly higher in the female patients than in the male patients (p<0.0001). In female patients, CRP and ESR correlated with time spent at oxygen saturation (T%SaO2)<90 (R=0.327, p=0.029 and R=0.301, p=0.05, respectively), T%SaO2<85 (R=0.482, p=0.001 and R=0.409, p=0.006, respectively), oxygen desaturation index (ODI) (R=0.298, p=0.047 and R=0.340, p=0.026, respectively), lowest oxygen saturation (SaO2) (R=-0.293, p=0.051 and R=-0.374, p=0.013, respectively), mean SaO2 (R=-0.408, p=0.005 and R=-0.385, p=0.011, respectively). In male patients, CRP correlated with T%SaO2<90 (R=0.267, p=0.009), T%SaO2<85 (R=0.279, p=0.006), mean SaO2 (R=-0.284, p=0.006) and fibrinogen correlated with T%SaO2<90 (R=0.282, p=0.028), and mean SaO2 (R=-0.252, p=0.05). In conclusion, increased values of systemic inflammatory markers and their correlations with sleep data observed in our study support other studies suggesting the possible involvement of inflammation in OSA. As this correlation is more apparent in female patients then the males, it suggests that there may be a stronger relation between OSA development and inflammation in females. Higher levels of CRP, fibrinogen, and ESR may result from the combined interactions of obesity, metabolic syndrome (MetS) and nocturnal hypoxia.

Rapid eye movement dependent central apnea with periodic leg movements.

Central sleep apnea is a period of at least 10 s without airflow, during which no ventilatory effort is present. Most of the central apneas occur in Non-Rapid eye movement (NREM) sleep. Central apnea occuring in Rapid eye movement (REM) sleep is extremely rare. We present our patient who had a diagnosis of obstructive sleep apnea in another sleep center since 2003. His Auto Continuous Positive Airway Pressure (CPAP) machine was disrupted so he admitted to our center to renew his machine and for daytime sleepiness while using his machine. The polysomnography revealed central apneas ending with respiratory arousals and periodic leg movements in rapid eye movement (REM) stage. We found no cause for central apneas. The patient benefited from servo ventilator therapy. We present this case as an unusual form of central apnea with the review of the literatures. Even the patients diagnosed as obstructive sleep apnea should be analyzed carefully. The diagnosis and the therapeutic approach may change in the favor of the patient.

The relationship between serum YKL-40 levels and severity of asthma.

YKL-40 (chitinase-3-like-1) has been introduced as a marker of inflammation in asthma. The aim of this study was to determine the role of YKL-40 in asthma and to evaluate the relationship between YKL-40 and asthma severity.In the study, 60 non-smoker asthma patients without additional diseases (aged between 20-60 years, female: 34) were grouped [Group I: Well controlled asthma patients (n: 30), Group II: Patients during acute exacerbation of asthma (n: 30)]. Healthy non-smoker female individuals were included in Group III (n: 30) as a control group. The level of serum YKL-40 of all groups were determined by ELISA. Also, serum YKL- 40 level was correlated with age, asthma duration in years, body mass index (BMI), forced expiratory volume in first second/ forced vital capacity (FEV1/FVC, %), FEV1 (%), and total IgE levels of asthma patients. Mean serum YKL-40 level was highest in patients during acute exacerbation of asthma (36.36±10.49 ng/ml) while mean serum YKL-40 level was the lowest (13.20±5.60 ng/ml) in the control group. There was a negative significant correlation between the serum YKL-40 levels and FEV1 (%) in patients during acute exacerbation of asthma. There were no significant correlations between the serum YKL-40 levels and other variables in group II.We found that increased serum YKL-40 levels may be used as a marker for evaluation of asthma severity and genetic polimorphism.

Chitinases and lung diseases.

Chitinase enzymes that hydrolize chitin and some articficial substrates are expressed in human despite lacking of the endogenous chitin within the body. Chitinases phatophysiological functions within human are not fully known. Recent evidence revealed that chitinases may have role into some processes of immune responses and inflammatory system. In this review, we discuss the role of chitinases in lung diseases based on the available information from the literature.