Leptin levels in children with obstructive sleep apnea syndrome.

INTRODUCTION: The aim of this study is to assess the effect of obstructive sleep apnea syndrome (OSAS) severity on leptin levels in children. PATIENTS AND METHODS: Children with habitual snoring underwent overnight polysomnography. Fasting venous blood samples were obtained between 8 AM and 9 AM, following the night of the sleep study. Children with an apnea-hypopnea index of ≥ 5/h were included in the moderate-to-severe OSAS group while those with an apnea-hypopnea index of < 5/h formed the mild OSAS/primary snoring group. RESULT: 47 children (51% male and 49% female; mean age 7.8 ± 2.6 years) were recruited. Twenty seven participants were diagnosed with moderate-to-severe OSAS, and twenty children who had AHI < 5 were included in the mild OSAS/primary snoring. The two groups did not differ regarding age, gender and body mass index z score (p> 0.05). Furthermore there were no differences in log serum leptin levels (p= 0.749). Log serum leptin levels correlated with the BMI z score in the whole study group (p= 0.001; r= 0.499) but they were not associated with apnea-hypopnea index, mean and lowest oxygen saturation during sleep. CONCLUSIONS: Serum leptin levels are affected by adiposity but not by OSAS severity among children with habitual snoring.

Clinical factors affecting the direct cost of patients hospitalized with acute exacerbation of chronic obstructive pulmonary disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a disease of increasing significance in terms of economic and social burden due to its increasing prevalence and high costs. Direct costs of COPD are mostly associated with hospitalization expenditures. In this study, our objective was to investigate the costs of hospitalization and factors affecting these costs in patients hospitalized due to acute exacerbation of COPD (AECOPD). METHODS: A total of 284 patients hospitalized AECOPD were included in the study. Data were examined retrospectively using the electronic hospital charts. RESULTS: Mean duration of hospitalization was 11.38 ± 6.94 days among study patients. Rates of admission to the intensive care unit, initiation of non-invasive mechanical ventilation (NIMV) and invasive mechanical ventilation (MIV) were 37.3% (n=106), 44.4% (n=126) and 18.3% (n=52) respectively. The rate of mortality was 14.8% (n=42). Mean cost of a single patient hospitalized for an AECOPD was calculated as $1765 ± 2139. Mean cost of admission was $889 ± 533 in standard ward, and $2508 ± 2857 in intensive care unit (ICU). The duration of hospitalization, a FEV1% predicted value below 30%, having smoked 40 package-years or more, the number of co-morbidities, NIMV, IMV, ICU, exitus and the number of hospitalizations in the past year were among the factors that increased costs significantly. Hospital acquired pneumonia, chronic renal failure and anemia also increased the costs of COPD significantly. CONCLUSION: The costs of treatment increase with the severity of COPD or with progression to a higher stage. Efforts and expenditures aimed at preventing COPD exacerbations might decrease the costs in COPD.

Serum asymmetric dimethylarginine, nitrate, vitamin B(12), and homocysteine levels in individuals with pulmonary embolism.

We aimed to analyze the pre- and posttreatment serum asymmetric dimethylarginine (ADMA), nitrate (NO(3)), vitamin B(12) and homocysteine levels in pulmonary embolism (PTE) patients and to determine the prognostic value of these variables in predicting chronic thromboembolic pulmonary hypertension (CTEPH). This study was conducted in 64 patients. The patients were classified into the two groups: patients with normal pulmonary artery pressure (PAP) (group I) and patients with high PAP with persistent lung perfusion defects or who died at the end of 3 months of therapy (group II). We found statistically significant differences between two groups with respect to the partial oxygen pressure, the oxygen saturation, and the PAP, but there was no difference between the two groups with respect to the pretreatment ADMA, NO(3), or homocysteine levels. The vitamin B(12) levels were higher in group II. The NO(3) levels increased and the ADMA and vitamin B(12) levels decreased with treatment in both groups. These results suggest that these parameters are not predictive of the development of CTEPH.

Working conditions and pneumoconiosis in Turkish coal miners between 1985 and 2004: a report from Zonguldak coal basin, Turkey.

In Turkey, bituminous coal mining is performed only in Zonguldak coal basin since 1940. Pneumoconiosis surveillance programs and dust control measures are in effect, but published pneumoconiosis data from this area is lacking. In this study, we aimed to evaluate the change in prevalence and case detection between 1985 and 2004 and assess the correlation between the dust concentration in workplaces and the prevalence of pneumoconiosis. Data on respirable dust concentrations and number of workers diagnosed as pneumoconiosis between 1985 and 2004 were obtained from Turkish Coal Enterprises authorities. Mean respirable dust concentrations in workplaces underground and on the ground were 1.66 mg/m(3) and 0.73 mg/m(3) respectively. Total number of workers decreased from 38.231 in 1985 to 12.261 in 2004 including 8932 underground workers. In this period, pneumoconiosis has not been reported in the ground workers. Incidence of pneumoconiosis ranged between 0.17-2.8 percent and prevalence ranged between 1.23-6.23 percent between 1985 and 2004. Radiologic opacities compatible with pneumoconiosis were predominantly small opacities. This is the first report about the incidence and prevalence rate of coal worker's pneumoconiosis in the main coal mining area of Turkey. Dust measurement and screening standards should be improved and adapted to international standards and we conclude that surveillance data should be closely monitored in this region and further epidemiologic studies in this area are warranted.

Prevalence of major obstructive sleep apnea syndrome symptoms in coal miners and healthy adults.

Obstructive sleep apnea syndrome obstructive sleep apnea syndrome is associated with symptoms including habitual snoring, witness apnea and excessive daytime sleepiness. Also obstructive sleep apnea syndrome is related to some occupations which are needed attention for work accident. We aimed to determine the prevalence of snoring, witnessed apnea and excessive daytime sleepiness in coal workers and healthy adults in Zonguldak city center, and also evaluate the differences between these groups. This study consisted of 423 underground coal workers and 355 individuals living in centre of Zonguldak. Study and comparison group were chosen by nonstratified randomized sampling method. Data were collected by a questionnaire that included information regarding snoring, witnessed apnea and excessive daytime sleepiness. Mean age was 43.3 ± 6.05 years in miners and 44.3 ± 11.8 years in comparison group. In miners, snoring frequency was determined as 42.6%, witnessed apneas were 4.0%, and daytime sleepiness were 4.7%. In comparison group, these symptoms were 38.6%, 4.8% and 2.8% respectively. There were no statistical differences between coal workers and comparison group in these symptoms. Also snoring prevalence was higher in smoker miners. We found that major symptoms of obstructive sleep apnea syndrome in coal workers are similar to general population in Zonguldak. Further studies that constucted higher populations and with polysomnography are needed to evaluate these findings.

Lung clearance of 99mTc-DTPA in ankylosing spondylitis.

The association of ankylosing spondylitis (AS) and lung parenchyma abnormalities has been shown in previous studies by radiological and pulmonary function tests. Technetium-99m diethylene triamine pentaacetic acid ((99m)Tc-DTPA) dynamic lung scanning is an easy, noninvasive method to assess alveolar-capillary barrier permeability. We aimed to study the abnormalities in pulmonary clearance of (99m)Tc-DTPA in patients with AS, and the presence of any correlation between this clearance and the radiological and pulmonary function tests. We studied twenty-one nonsmoker patients with AS who were compared to 21 age and sex matched healthy volunteers. All subjects underwent pulmonary function tests and pulmonary scintigraphy with (99m)Tc-DTPA to evaluate pulmonary clearance. Clearance half time (T(1/2)) of (99m)Tc-DTPA through the lungs was calculated by placing a monoexponential fit on the 30 min activity curves. High resolution CT and pulmonary function tests were performed for each patient. Our results showed the following: Spirometric parameters of forced vital capecity (FVC) and theratio of forced expiratory value in 1sec/FVC (FEV1%) scores were worse in patients compared to the control group (P<0.005 and P<0.05, respectively). Clearance half time was longer in AS group than in the control group (58.45+/-7.59 and 51.62+/-4.79 min, respectively; P<0.05). There was a negative correlation between T(1/2) value and FEV1% (r=-0.876, P< 0.01), of AS patients and the control group. Additionally, there were moderate positive correlation between T(1/2) and FVC (r=0.705, P<0.001), weak positive correlation between T(1/2) and FEF2575 (r=0.493, P<0.05), and T(1/2) and DLCO (r=0.444, P<0.05). A positive correlation was found between the duration of the disease and T(1/2) (r=0.44, P<0.05). In conclusion, longer T(1/2) values and lower FVC values in nonsmoker AS patients may suggest not only the pulmonary involvement in AS but also the duration of the disease.

Giant bulla mimicking tension pneumothorax.

In the chest X-ray, we observe tension pneumothorax (TPX) as wide radiolucent view in a hemithorax and pushing the mediastinal structures contralateral. Giant bulla may mimic TPX with wide radiolucent view and mediastinal shift. The present report includes giant pulmonary bulla in 35-year-old woman. The giant bulla was diagnosed as a TPX in emergency, and chest tube was performed. The differentiation between TPX and a giant bulla may be very difficult. The therapies of these two similar entities are completely different. So that, we must be careful about anamnesis, physical examination and radiology for true diagnosis.

Effect of adenoidectomy and/or tonsillectomy on cardiac functions in children with obstructive sleep apnea.

BACKGROUND/AIMS: We aimed to determine the effects of adenoidectomy and/or tonsillectomy (AT) on cardiac functions in children with adenoid and/or tonsillary hypertrophy and obstructive sleep apnea syndrome (OSAS) by using echocardiography with tissue Doppler imaging facility (TDI). METHODS: Twenty-nine children with adenoid and/or tonsillary hypertrophy and OSAS and 26 children with primary snoring entered the study. Cardiac functions were assessed by echocardiography with TDI in both groups. Tests were repeated in the OSAS group 6 months after treatment with AT. RESULTS: Echocardiography showed a decrease in estimated pulmonary artery systolic pressure from 31 +/- 4.2 to 13.1 +/- 2.3 (p < 0.001). In TDI, tricuspid E(m) and E(m)/A(m) increased from 11.0 +/- 2.7 to 13.5 +/- 2.7 cm/s (p < 0.001), and 1.46 +/- 0.52 to 1.82 +/- 0.53 (p = 0.004), respectively, following AT, indicating improvement in right ventricular diastolic dysfunction. Similarly, mitral E(m) and E(m)/A(m) increased from 12.3 +/- 2.1 to 16.3 +/- 2.7 cm/s, and from 1.65 +/- 0.51 to 2.30 +/- 0.54, respectively (p < 0.001). There was no significant difference between postoperative values and control group values. CONCLUSION: TDI is a technique able to detect diastolic dysfunction unnoticeable by conventional echocardiography. Following AT, we observed improvement in both left and right ventricular diastolic functions using TDI.

Examination of lung toxicity, oxidant/antioxidant status and effect of erdosteine in rats kept in coal mine ambience.

Occupational exposure to coal dust causes pneumoconiosis and other diseases. Reactive oxygen species (ROS) have been implicated in the pathogenesis of coal dust-induced lung toxicity. In this experimental study, we investigated the oxidant/antioxidant status, nitric oxide (NO) and hydroxyproline (HP) levels in lungs and blood of rats exposed to coal dust in mine ambience. In addition, we also investigated the attenuating effects of erdosteine. At the end of the experiment processes, tissue levels of HP, malondialdehyde (MDA) and NO, as well as the activities of superoxide dismutase, glutathione peroxidase, catalase, xanthine oxidase (XO), myeloperoxidase (MPO) and proinflammatory cytokines (IL-6 and TNF-α) were evaluated in the lung tissues, plasma samples or erythrocytes of rats. Exposure to coal dust resulted in a significant increase in the oxidant parameters (MDA, NO levels, and XO activity) and HP levels, as compared to the controls. A decrease in activities of antioxidant enzymes, and an increase in MPO activity were found in the study group, compared to the controls. Increased NO levels of lung were found in the study groups, that were significantly reduced by erdosteine. Our studies provide evidence that supports the hypothesis for ROS mediated coal workers' pneumoconiosis. Erdosteine may be beneficial in the coal dust-induced lung toxicity via antioxidant and free radical scavenger properties.

Color Doppler evaluation of the ocular arterial flow changes in chronic obstructive pulmonary disease.

PURPOSE: To evaluate the hemodynamic changes in the extraocular orbital vessels of the patients with chronic obstructive pulmonary disease (COPD), using color Doppler ultrasonography (CDU) technique, and to compare the results with those of healthy control subjects. METHODS: Forty-five patients with COPD and 17 healthy control subjects were included in this study. Patients with COPD were classified according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD). Fifteen patients of stage I COPD (mild airflow limitation), stage II COPD (worsening airflow limitation) or stage III COPD (severe airflow limitation) were enrolled into Group I, II and III, respectively. End tidal carbon dioxide (EtCO(2)), peripheral oxygen saturation (SpO(2)), pulse rate (PR) and respiratory rate (RR) were measured by using capnograph/pulse oximeter in all patients. Measurements were performed in only one randomly chosen eye of each participant. The peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistance index (RI) were measured in the ophthalmic artery (OA), central retinal artery (CRA), lateral short posterior ciliary artery (LPCA) and medial short posterior ciliary artery (MPCA), using CDU technique. RESULTS: The PSV measurements of the OA were significantly higher in Groups II and III compared to control group (p < 0.01, p < 0.001, respectively). The RI values from OA and CRA were significantly higher in Group II and III than the control group (p < 0.05). The RI values of LPCA and MPCA were also significantly higher in Group II than the control subjects (p < 0.05). When RI values were compared, mean values of LPCA and MPCA were significantly lower in Group III than in Group II (p < 0.05). There were no significant differences between Group I and control patients about PSVs, EDVs and RI values of all arteries Statistically significant correlations were found for the EtCO(2) with PSV (r = 0.53, p < 0.01) and EDV (r = 0.51, p < 0.01) of the OA. Statistically significant correlations were also found for the SpO2 with RI (r = -0.34, p < 0.05) in the OA. CONCLUSION: We concluded that COPD is associated with impaired retrobulbar hemodynamics, especially in the ophthalmic artery. Moreover, central retinal and posterior ciliary arteries with increased resistance are also found to be affected when compared with healthy control eyes.

Prevalence of obstructive sleep apnea syndrome and associated symptoms in 3--11-year-old Turkish children.

Our objective was to investigate the prevalence of sleep-disordered breathing (SDB) and obstructive sleep apnea syndrome (OSAS) in 3-11-year-old Turkish children. A cross-sectional study was conducted in Zonguldak, northwestern Turkey. Symptomatic children were identified by using a self-administered questionnaire and were classified into three groups: nonsnorers, occasional snorers, and habitual snorers. All habitual snoring children were invited to undergo polysomnography (PSG). Nine hundred fifty-four children (79.5%) were nonsnorers, 205 (17.2%) were occasional snorers, and 39 (3.3%) were habitual snorers. There was no significant relationship between gender and habitual snoring (male, 3.4%; female, 3.1%; P > 0.05; odds ratio (OR), 1.13; 95% confidence interval (CI), 0.59-2.14). There was a statistically significant relationship between habitual snoring and allergic rhinitis (OR, 4.23; 95% CI, 2.14-8.35). Four children who snored every night, and who had apnea spells and/or troubled sleep, underwent adenoidectomy and/or tonsillectomy before polysomnographic evaluation because of clinical detoriation. Twenty-eight of 39 children with habitual snoring participated in PSG evaluation. PSG revealed that 11 children (0.9% of the total population) had OSAS. When 4 operated children were added to these 28 children, we found the minimum prevalence of OSAS to be 1.3% in our study group. There was a significant correlation between OSAS and troubled sleeping (P <0.001; OR, 4.37; 95% CI, 1.33-14.3). We found the prevalence of habitual snoring to be 3.3% in Turkish children by using self-administered questionnaires. Allergic rhinitis was significantly correlated with habitual snoring. Minimum estimated prevalence of OSAS was found to be 1.3%.

Comparison of early and late pleuropulmonary findings of ankylosing spondylitis by high-resolution computed tomography and effects on patients' daily life.

Ankylosing spondylitis (AS) is a multisystemic disease and extra-articular features may develop as pleuropulmonary involvement. We aimed to show and compare the early and late pleuropulmonary findings of AS and its effects on patients' daily life by causing dyspnea. The study consisted of 38 patients (33 male, 5 female). All patients met the New York criteria for AS. Patients were divided into two groups for comparison of early (disease duration <10 years and normal chest X-ray, 18 patients) and late (disease duration >/=10 years and normal or abnormal chest X-ray, 20 patients) manifestations. All patients underwent high-resolution computed tomography (HRCT) and pulmonary function tests. A questionnaire was completed to measure perceived shortness of breath (dyspnea score) with activities of daily living such as dressing, shaving or walking. HRCT findings were abnormal in 27 of the 38 patients (73%). Pulmonary involvement was high in early AS (61.1%). The number of findings in early and late AS found were as follows: mosaic pattern (9/10), parenchymal micronodules (2/3), parenchymal bands (5/9), bronchial wall thickening (2/10), ground-glass opacity (7/7), and interlobular septal thickening (6/10). A moderate correlation was obtained between presence of mosaic pattern and forced midexpiratory flow rate (FEF(25-75)) values indicating small airway obstruction (r=0.346, p=0.019). The dyspnea score was statistically higher in patients with AS having pulmonary involvement than those without involvement. Pulmonary involvement is common in early AS compared to late AS. The involvement of small airways was found frequently as interstitial lung disease in early and late AS. This study also suggests that AS with pulmonary involvement may affect patients' daily life by causing dyspnea, which is why early detection of pulmonary lesions may have clinical importance and should be studied in a large cohort.

Prognostic value of serum procalcitonin and C-reactive protein levels in critically ill patients who developed ventilator-associated pneumonia.

INTRODUCTION: Ventilator-associated pneumonia (VAP) is an important cause of mortality and morbidity in critically ill patients. We sought to determine the prognostic value of procalcitonin (PCT) and C-reactive protein (CRP) kinetics in critically ill patients who developed VAP. METHODS: Patients who were admitted to the intensive care unit (ICU) and developed VAP were eligible. Patients were followed for 28 days after the pneumonia diagnosis and blood samples for PCT and CRP were collected on the day of the pneumonia diagnosis (D0), and days 3 (D3) and 7 (D7) after the diagnosis. Patients were grouped as survivors and non-survivors, and the mean PCT and CRP values and their kinetics were assessed. RESULTS: In total, 45 patients were enrolled. Of them, 22 (48.8%) died before day 28 after the pneumonia diagnosis. There was no significant difference between the survivor and non-survivor groups in terms of PCT on the day of pneumonia diagnosis or CRP levels at any point. However, the PCT levels days 3 and 7 were significantly higher in the non-survivor group than the survivor group. Whereas PCT levels decreased significantly from D0 to D7 in the survivor group, CRP did not. A PCT level above 1 ng/mL on day 3 was the strongest predictor of mortality, with an odds ratio of 22.6. CONCLUSION: Serum PCT was found to be a superior prognostic marker compared to CRP in terms of predicting mortality in critically ill patients who developed VAP. The PCT level on D3 was the strongest predictor of mortality in VAP.

Antituberculosis drug resistance patterns in two regions of Turkey: a retrospective analysis.

BACKGROUND: The emergence of Mycobacterium tuberculosis strains resistant to antituberculosis agents has recently received increased attention owing largely to the dramatic outbreaks of multi drug resistance tuberculosis (MDR-TB). METHODS: Patients residing in Zonguldak and Kayseri provinces of Turkey with, pulmonary tuberculosis diagnosed between 1972 and 1999 were retrospectively identified. Drug susceptibility tests had been performed for isoniazid (INH), rifampin (RIF), streptomycin (SM), ethambutol (EMB) and thiacetasone (TH) after isolation by using the resistance proportion method. RESULTS: Total 3718 patients were retrospectively studied. In 1972-1981, resistance rates for to SM and INH were found to be 14.8% and 9.8% respectively (n: 2172). In 1982-1991 period, resistance rates for INH, SM, RIF, EMB and TH were 14.2%, 14.4%, 10.5%, 2.7% and 2.9% (n: 683), while in 1992-1999 period 14.4%, 21.1%, 10.6%, 2.4% and 3.7% respectively (n: 863). Resistance rates were highest for SM and INH in three periods. MDR-TB patients constituted 7.3% and 6.6% of 1982-1991 and 1992-1999 periods (p > 0.05). CONCLUSION: This study demonstrates the importance of resistance rates for TB. Continued surveillance and immediate therapeutic decisions should be undertaken in order to prevent the dissemination of such resistant strains.

Evaluation of paranasal sinus mucosa in coal worker's pneumoconiosis: a computed tomographic study.

OBJECTIVE: To evaluate by computed tomographic scanning the paranasal mucosal changes of coal workers with and without pneumoconiosis. METHODS: Examination of images and scores from paranasal computed tomographic scans. The study participants were 26 coal workers with pneumoconiosis, 29 coal workers without pneumoconiosis, and 20 controls. All were men. The extent and patterns of inflammatory paranasal sinus disease were evaluated on computed tomographic scans by 2 radiologists using the terminology and definitions of Newman and associates. RESULTS: Interobserver agreement for the presence of abnormalities was from good to excellent (kappa, 0.63-0.89). The mucosal scores of individuals and groups were higher for coal workers than for control subjects. Both scores were significantly higher in the pneumoconiosis group than in the 2 other groups. CONCLUSIONS: This study shows that paranasal sinuses were affected more severely in coal workers than in control subjects. In coal workers with pneumoconiosis, the affection was most severe. The relationship between coal dust exposure and paranasal mucosal changes needs further study.

Presence and HRCT quantification of bronchiectasis in coal workers.

PURPOSE: The purpose of this study was to evaluate the presence of bronchiectasis in coal workers with or without coal worker pneumoconiosis (CWP) and to assess the extent of bronchiectasis, severity of bronchial wall dilatation and thickening by high resolution computed tomography (HRCT). MATERIALS AND METHODS: The retrospective study consisted of HRCT archieves of 93 coal workers. The coal workers with previous diagnosis of COPD (six), asthma (one) and tuberculosis (three) were excluded. Five coal workers with progressive massive fibrosis were not included into the study. The resulting patient group consisted of 78 patients (43 CWP; 35 non-CWP). Pneumoconiosis profusions of CWP workers were between p0/1 and p2/2 according to ILO 1980 chest X-ray classification. HRCT examinations of all subjects were evaluated for the presence, extent, dilatation and thickness of bronchiectasis. Analysis of extent, dilatation and thickness were performed according to established criteria. RESULTS: The diagnosis of bronchiectasis was put on 19 of 43 CWP (44.1%) and 7 of 35 non-CWP workers (20.0%). There were statistically significant differences between bronchiectasis positive and negative coal workers with CWP concerning age and exposure duration (P = 0.012 and 0.009, respectively). Then, multiple logistic regression analysis was performed to define exact risk factors. Exposure duration was only found to be related with presence of bronchiectasis [(odds ratio) OR = 1.494, 95% confidence interval 1.168-1.912]. CONCLUSIONS: The data from the present study shows that bronchiectasis is frequent and severe in CWP workers than without. Bronchiectasis is influenced by coal dust exposure. Thus, coal dust protection measures must be controlled efficiently to prevent bronchiectasis in coal workers.

Comparison of chest radiography and high-resolution computed tomography findings in early and low-grade coal worker's pneumoconiosis.

INTRODUCTION: High-resolution computed tomography (HRCT) is more sensitive than chest X-ray (CXR) in the depiction of parenchymal abnormalities. We aimed to present and compare CXR and HRCT findings in coal workers with and without early and low-grade coal worker's pneumoconiosis (CWP). MATERIALS AND METHODS: 71 coal workers were enrolled in this study. All workers were male. The CXR and HRCT of those workers were obtained and graded by two trained readers. HRCT's were graded according to Hosoda and Shida's Japanese classification. After grading, 67 workers with CXR profusion 0/0-2/2 were included in the study. Four patients with major opacity were excluded. Profusion 0/1 to 1/1 cases were accepted as early and profusion 1/2 and 2/2 cases as low-grade pneumoconiosis. RESULTS: Discordance between CXR and HRCT was high. Discordance rate was found higher in the early pneumoconiosis cases with negative CXR than low-grade pneumoconiosis (60, 36 and 8%, respectively). When coal miners with normal CXR were evaluated by HRCT, six out of 10 cases were diagnosed as positive. In low-grade pneumoconiosis group, the number of patients with positive CXR but negative HRCT were low in comparison to patients with CXR negative and early pneumoconiosis findings. Most of the CXR category 0 patients (10/16) were diagnosed as category 1 by HRCT. Eleven cases diagnosed as CXR category 1 were diagnosed as category 0 (7/11) and category 2 (4/11) by HRCT. In CXR category 2 (eight cases), there were four cases diagnosed as category 1 by HRCT. CONCLUSIONS: Discordance between CXR and HRCT was high, especially for CXR negative and early pneumoconiosis cases. The role of CXR in screening coal workers to detect early pneumoconiosis findings should be questioned. We suggest using HRCT as a standard screening method instead of CXR to distinguish between normal and early pneumoconiosis.

Antioxidant response at early stages and low grades of simple coal worker's pneumoconiosis diagnosed by high resolution computed tomography.

In miners exposed to coal dusts, coal worker's pneumoconiosis (CWP) can occur. The purpose of the present study is to better understand the relations between coal dust exposure and activities of blood plasma antioxidant enzymes, namely, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and lipid peroxidation end product malondialdehyde (MDA) concentration in coal workers with early and low grade simple CWP diagnosed by high resolution computed tomography (HRCT). Forty-three coal workers who had profusions of 0/1-2/2 according to ILO 1980 chest X-ray (CXR) classification, 43 coal workers without CWP (control group 1) and 44 healthy subjects (control group 2) who were randomly selected from the population register or recruited from the hospital staff were enrolled. Coal workers were reevaluated by HRCT (Hosoda-Shida classification) due to its higher sensitivity than standard CXR. Then, blood plasma SOD and GSH-Px activities and MDA plasma levels were measured. CWP was found positive in 46 of 89 coal workers by HRCT evaluation. Profusion 0 (P0, CWP not present), profusion 1 (P1, early CWP) and profusion 2 (P2, low grade CWP) were found in 43, 23 and 19 of patients found to have CWP by HRCT, respectively. We had no worker with profusion 3 (P3). Complicated CWP was shown in four of 46 patients and thesecases were excluded as the study was restricted to early and low-grade pneumoconiosis. In respect to the plasma levels of MDA and plasma activities of SOD and GSH-Px, statistically significant differences were found between CWP cases and control groups (p < 0.01, p < 0.01, p < 0.001 respectively). Statistical differences were also obtained for the plasma activities of SOD and GSH-Px and levels of MDA in relation to HRCT profusions (p < 0.05). In conclusion, these findings suggest an oxidative stress due to increased free radicals and reactive oxygen metabolite production in early stages and low grades of simple CWP diagnosed by HRCT.

Smoking prevalence, behaviour and nicotine addiction among coal workers in Zonguldak, Turkey.

To assess the smoking status of coal workers, as coal dust exposure and concomitant cigarette smoking contribute to the increased prevalence of pulmonary interstitial fibrosis, chronic obstructive pulmonary disease and other pulmonary diseases. A survey was conducted to determine the smoking prevalence, behaviour and nicotine addiction in coal workers. The target population consisted of 475 underground coal workers who lived in Zonguldak city of Turkey, and we reached 389 of them. Each subject completed a detailed smoking history questionnaire (included 56 question). Chest X-rays and pulmonary function tests were performed to evaluate patients' related diseases and complications. Smoking status of the workers was as follows; Sixty-nine never smokers (17.7%), 62 ex-smokers (15.9%) and 258 current smokers (66.3%). The mean age of starting smoking was similar among ex and current smokers (15.9 +/- 4.2 versus 15.0 +/- 4.0). The most common reason for starting smoking was smoking interest (50%) and friends' influence (15.5%). The most frequent reason stated for successful smoking cessation was experience of smoking-related symptoms or development of a medical condition (51%). The most important reason given by current smokers for smoking cessation attempts was increased chance of developing lung cancer, pneumoconiosis and other diseases (22.9%). Nicotine addiction was assessed by the Fagerstroem test. Mild (0-3 points), moderate (4-6) and severe (7 or more) addiction ratios were found to be 39.1%, 44.2% and 16.7% respectively. Ex-smokers had the highest prevalence of large and small airway obstruction on spirometry. Smoking prevalence is high in coal workers living in Zonguldak city of Turkey. Most of the smokers know that smoking is dangerous and want to quit smoking. A detailed smoking history during medical surveillance may help the occupational physician to develop a system in which such individuals can be referred to comprehensive smoking cessation programs.

Cardiac autonomic activity in obstructive sleep apnea: time-dependent and spectral analysis of heart rate variability using 24-hour Holter electrocardiograms.

To analyze the function of cardiac autonomic regulation in patients with obstructive sleep apnea syndrome (OSAS), we enrolled 36 patients with OSAS and divided them according to the apnea hypopnea index (AHI) into 2 groups: Group I (n=19) had mild OSAS (AHI < 20) and Group II (n=17) had severe OSAS (AHI > or = 20). The findings were compared with those of 24 healthy control subjects who were matched for age, sex, blood pressure, and body mass index. All participants underwent 24-hour Holter monitoring, with continuous time-dependent and spectral analysis of heart rate variability. In addition, we performed arrhythmia analysis. Frequent or repetitive ventricular arrhythmias (> or = 30 premature ventricular beats/hour) were detected in 15 (42%) patients with OSAS and in 6 (25%) members of the control group. In both mild and severe OSAS, SDNN was significantly lower than in controls, and SDANN findings were similar. In mild OSAS, RMSSD values were not significantly lower than in controls, but in severe OSAS they were. The ULF, VLF, LF and LF/HF values of both groups of OSAS patients were significantly higher than those of controls, but their HF values were lower. The mean LF/HF ratio during the same period was significantly higher in Group II than in Group I and the control group. Our results suggest that cardiac autonomic activity may be altered in patients with OSAS throughout a 24-hour period, that this alteration occurs even in the absence of hypertension, heart failure, or other disease states, and that it is linked to the severity of OSAS.