Zuleyha Bingol

Clinical Predictors of Obesity Hypoventilation Syndrome in Obese Subjects With Obstructive Sleep Apnea

BACKGROUND: Arterial blood gas (ABG) analysis is not a routine test in sleep laboratories due to its invasive nature. Therefore, the diagnosis of obesity hypoventilation syndrome (OHS) is underestimated. We aimed to evaluate the differences in subjects with OHS and pure obstructive sleep apnea (OSA) and to determine clinical predictors of OHS in obese subjects. METHODS: Demographics, body mass index (BMI), Epworth Sleepiness Scale score, polysomnographic data, ABG, spirometric measurements, and serum bicarbonate levels were recorded. RESULTS: Of 152 obese subjects with OSA (79 females/73 males, mean age of 50.3 ± 10.6 y, BMI of 40.1 ± 5.6 kg/m2, 51.9% with severe OSA), 42.1% (n = 64) had OHS. Subjects with OHS had higher BMI (P = .02), neck circumference (P < .001), waist circumference (P < .001), waist/hip ratio (P = .02), Epworth Sleepiness Scale scores (P = .036), ABG and serum bicarbonate levels (P < .001), apnea-hypopnea index (P = .01), oxygen desaturation index (P < .001), and total sleep time with SpO2 < 90% (P < .001) compared with subjects with pure OSA (n = 88). They also had lower daytime PaO2 (P < .001), sleep efficiency (P = .032), mean SpO2 (P < .001), and nadir SpO2 (P < .001). Serum bicarbonate levels and nadir SpO2 were the only independent predictive factors for OHS. A serum bicarbonate level of ≥ 27 mmol/L as the cutoff gives a satisfactory discrimination for the diagnosis of OHS (sensitivity of 76.6%, specificity of 74.6%, positive predictive value of 54.5%, negative predictive value of 88.9%). A nadir SpO2 of < 80% as the cutoff gives a satisfactory discrimination for the diagnosis of OHS (sensitivity of 82.8%, specificity of 54.5%, positive predictive value of 56.9%, negative predictive value of 81.4%). When we used a serum bicarbonate level of ≥ 27 mmol/L and/or a nadir SpO2 of < 80% as a screening measure, only 3 of 64 subjects with OHS were missed. CONCLUSIONS: Serum bicarbonate level and nadir saturation were independent predictive factors for the diagnosis of OHS.

Relationship between parenchymal involvement and obstructive sleep apnea in subjects with sarcoidosis.

Increased obstructive sleep apnea (OSA) incidence has been reported in sarcoidosis. However, no research has been conducted to determine the relation between OSA and pulmonary parenchymal involvement in sarcoidosis.

Follow-up of 1887 patients receiving tumor necrosis-alpha antagonists: Tuberculin skin test conversion and tuberculosis risk

To evaluate the characteristics of patients who developed tuberculosis while receiving tumor necrosis factor‐alpha (TNF‐α) antagonists and the related factors with tuberculosis.

The Predictors of Obesity Hypoventilation Syndrome in Obstructive Sleep Apnea

Background: As obesity increases, the frequency of obstructive sleep apnea and obesity hypoventilation syndrome increases also. However, obesity hypoventilation syndrome frequency is not known, as capnography and arterial blood gas analysis are not routinely performed in sleep laboratories. Aims: To investigate the frequency and predictors of obesity hypoventilation syndrome in obese subjects. Study Design: Retrospective clinical study. Methods: Obese subjects who had arterial blood gas analysis admitted to the sleep laboratory and polysomnography were retrospectively analyzed. Subjects with restrictive (except obesity) and obstructive pulmonary pathologies were excluded. Demographics, Epworth-Sleepiness-Scale scores, polysomnographic data, arterial blood gas analysis, and spirometric measurements were recorded. Results: Of the 419 subjects, 45.1% had obesity hypoventilation syndrome. Apnea hypopnea index (p<0.001), oxygen desaturation index (p<0.001) and sleep time with SpO2<90% (p<0.001) were statistically higher in subjects with obesity hypoventilation syndrome compared to subjects with eucapnic obstructive sleep apnea. The nocturnal mean SpO2 (p<0.001) and lowest SpO2 (p<0.001) were also statistically lower in subjects with obesity hypoventilation syndrome. Logistic regression analysis showed that the lowest SpO2, oxygen desaturation index, apnea hypopnea index and sleep time with SpO2 <90% were related factors for obesity hypoventilation syndrome. Conclusion: Obesity hypoventilation syndrome should be considered when oxygen desaturation index, apnea hypopnea index and sleep time with SpO2 <90% are high.

Fractional Exhaled Nitric Oxide Measurement in Pulmonary Hypertension: A Follow-Up Study

Pulmonary hypertension (PH) is a fatal disease although significant improvements in treatment are achieved. Easily implemented and noninvasive prognostic techniques are needed while following-up these patients. The aim was to investigate the role of fractional exhaled nitric oxide (FeNO) in follow-up for patients with PH. In this longitudinal study, patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic PH (CTEPH) who were seen in PH Outpatient Clinic, Istanbul Faculty of Medicine, Istanbul University, were enrolled in the study. Echocardiography, 6-minute walking test, brain natriuretic peptide, and FeNO measurements were performed, and World Health Organization functional class was evaluated to all patients at baseline, and third, and sixth months. Right-heart catheterization and pulmonary function tests at the time of diagnosis were recorded. The study comprised 31 patients (23 women, 8 men; mean age: 53.4 ± 17.1 years) with PAH (n = 19) and CTEPH (n = 12) and 80 healthy controls. Patients with PH had lower FeNO values than the control group (16.5 ppb vs 19.8 ppb; P < .05). Fractional exhaled nitric oxide values did not change during follow-up and did not correlate with other follow-up measures except tricuspid annular plane systolic excursion values. Fractional exhaled nitric oxide was higher in the idiopathic PAH subgroup at baseline and at third month than patients with PAH associated with other diseases. Fractional exhaled nitric oxide did not change in patients who had clinical deterioration. As a conclusion; Patients with PH had lower FeNO values than healthy controls, but FeNO did not change significantly during follow-up. Large-scale studies with prolonged follow-up periods are needed to understand the role of FeNO in the follow-up of the patients with PH.

Does Obstructive Sleep Apnea Increase the Risk for Periodontal Disease?: A Case-control Study.

BACKGROUND A possible association between periodontitis and obstructive sleep apnea (OSA) has been suggested. The aim of this study is to compare periodontitis prevalence between controls and patients with OSA by assessing clinical periodontal parameters and gingival crevicular fluid (GCF) levels of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and high-sensitive C-reactive protein (hs-CRP); serum hs-CRP was also sampled. METHODS A case-control study was performed that included 163 individuals: 83 individuals (18 females and 65 males) with OSA and 80 non-OSA individuals (23 females and 57 males) as controls. The test group was classified according to OSA severity. Clinical periodontal measurements were recorded, and GCF samples were collected. GCF hs-CRP, IL-lβ, and TNF-α levels were analyzed using an enzyme-linked immunosorbent assay method. Serum hs-CRP was measured by latex-enhanced immunoturbidimetric assay. RESULTS Prevalence of periodontitis in the OSA group (96.4%) was significantly higher than in the control group (75% [P <0.001]). Severe periodontitis prevalence was higher in the OSA group than control group. All periodontal clinical parameters and GCF IL-lβ concentrations were significantly higher in patients with OSA than in controls (P = 0.001). No significant differences were found between the mild OSA and moderate-to-severe OSA groups. Additionally, there was no significant difference in GCF TNF-α and hs-CRP levels between the groups (P >0.05). Serum hs-CRP levels were significantly higher in patients with OSA. A significant correlation was found between GCF IL-1β and all clinical parameters. CONCLUSIONS Results demonstrated higher prevalence of periodontitis and higher levels of GCF IL-1β and serum hs-CRP in patients with OSA. However, there is still a need for randomized clinical trials testing oral care interventions.

Serum endothelial cell specific molecule-1 (endocan) levels in patients with obstructive sleep apnea.

OBJECTIVE To investigate the level of endothelial cell specific molecule-1 (endocan) in obstructive sleep apnea (OSA). METHODS Study group included subjects with OSA. Control group included subjects who had no OSA on polysomnography and nonobese healthy subjects from population who had no OSA symptoms. Endocan levels of OSA and non-OSA subjects were compared. RESULTS Totally 106 individuals (63 OSA, 43 non-OSA) were included. Endocan levels were higher in OSA subjects than controls (1.25 ± 0.4 ng/ml vs 0.93 ± 0.3 ng/ml, p < 0.001). Endocan levels were correlated with BMI (r = 0.456, p < 0.001) and daytime PaO2 (r = -0.266, p < 0.042). In linear regression analysis there was no factor related to endocan level. CONCLUSION Serum endocan is significantly higher in OSA. Further studies should be performed to better understand the relationship between endocan and OSA.

Tracheopathia osteochondroplastica: two unusual cases.

We describe 2 unusual cases of tracheopathia osteochondroplastica (TPO), one of them presenting with lung carcinoma and the other at an uncommon age. A 74-year-old man presented with chronic bronchitis and a left lower lobe lesion as detected on chest computed tomography. Flexible bronchoscopy revealed multiple calcified nodular lesions involving the anterior-lateral walls of the trachea and main bronchi. Histologic analysis of the tracheal nodules confirmed the presence of TPO. Squamous cell carcinoma was diagnosed by transthoracic needle aspiration of the pulmonary nodule. The relevance of coexistence of these 2 conditions remains unknown. Our second case was in a young man who presented with persistent cough and a chest computed tomography scan revealing multiple tracheal nodules. Numerous hard tracheal nodules distributed around the lower trachea and main bronchi were observed at flexible bronchoscopy. When the cough and dyspnea persists despite conventional empiric treatment, uncommon tracheobronchial pathologies, such as TPO, should be considered.

Vocal Cord Paralysis and Hypercapnic Respiratory Failure in a Patient with Familial Amyloidotic Polyneuropathy.

We herein report a patient case with familial amyloidotic polyneuropathy (FAP) who presented with vocal cord paralysis (VCP). A 60-year-old man with FAP (Gly89Gln) presented with hoarseness and snoring for the previous two years. A chest X-ray demonstrated cardiomegaly and bilateral diaphragmatic elevation. The findings of a restrictive pattern on spirometry and daytime hypercapnia were consistent with respiratory muscle weakness related to neuropathy [forced expiratory volume (FEV1): 38%, forced vital capacity (FVC): 39%, FEV1/FVC: 77, partial pressure of arterial oxygen (PaO2): 80 mmHg, partial pressure of carbon dioxide in arterial blood (PaCO2): 52 mmHg]. An ear-nose-throat examination showed VCP. Polysomnography revealed severe obstructive sleep apnea (OSA). FAP may cause OSA by VCP and hypercapnic respiratory failure by respiratory muscle weakness. Therefore, an ear-nose-throat examination, spirometry, arterial blood gases analysis and polysomnography are important for these patients.

Bicarbonate Level for Early Diagnosis of Obesity Hypoventilation Syndrome: Still Defining Boundaries--Reply.

In reply: We thank Drs Lemyze and Esquinas for their interest in our work.[1][1] The International Classification of Sleep Disorders, 3rd edition,[2][2] defines obesity hypoventilation syndrome (OHS) as the combined presence of obesity (body mass index >30 kg/m2) with awake arterial hypercapnia (