Impact of obstructive sleep apnoea on left ventricular mass and global function

Obstructive sleep apnoea syndrome (OSAS) might be a cause of heart failure. The present study aimed to assess left ventricular mass and myocardial performance index (MPI) in OSAS patients. A total of 67 subjects without any cardiac or pulmonary disease, referred for evaluation of OSAS, had overnight polysomnography and echocardiography. According to apnoea-hypopnoea index (AHI), subjects were classified into three groups: mild OSAS (AHI: 5-14; n=16), moderate OSAS (AHI: 15-29; n=18), and severe OSAS (AHI: ≥30; n=33). Thickness of interventricular septum (IVS) and posterior wall (LVPW) were measured by M-mode, along with left ventricular mass (LVM) and LVM index (LVMI). Left ventricular MPI was calculated as (isovolumic contraction time+isovolumic relaxation time)/aortic ejection time by Döppler echocardiography. There were no differences in age or body mass index among the groups, but blood pressures were higher in severe OSAS compared with moderate and mild OSAS. In severe OSAS, thickness of IVS (11.2 ± 1.1 mm), LVPW (11.4 ± 0.9 mm), LVM (298.8 ± 83.1 g) and LVMI (144.7 ± 39.8 g·m-2) were higher than in moderate OSAS (10.9 ± 1.3 mm; 10.8 ± 0.9 mm; 287.3 ± 74.6 g; 126.5 ± 41.2 g·m-2, respectively) and mild OSAS (9.9 ± 0.9 mm; 9.8 ± 0.8 mm; 225.6 ± 84.3 g; 100.5 ± 42.3 g·m-2, respectively). In severe OSAS, MPI (0.64 ± 0.14) was significantly higher than in mild OSAS (0.50 ± 0.09), but not significantly higher than moderate OSAS (0.60 ± 0.10). In conclusion, severe and moderate obstructive sleep apnoea syndrome patients had higher left ventricular mass and left ventricular mass index, and also left ventricular global dysfunction. Copyright©ERS Journals Ltd 2005

A longitudinal study on lung disease in dental technicians: What has changed after seven years?

Objectives: The aim of this 7-year follow-up study was to determine respiratory changes in dental technicians. Material and Methods: In our region, in the year 2005, 36 dental technicians were evaluated with a cross-sectional study on respiratory occupational diseases, and in 2012 we evaluated them again. Inclusion of information on respiratory symptoms and demographic features questionnaires was applied. Pulmonary function tests (PFT) were performed. Chest X-rays (CXR) were evaluated according to the ILO-2000 classification. For the comparisons of the technicians' findings in 2005 and 2012, data analyses were performed with the Wilcoxon test in addition to descriptive statistical procedures. Results: In 2012, 19 out of the 36 technicians continued to work in the same place, so we were able to evaluate their findings. The prevalence of respiratory symptoms in dental technician was as follows: dyspnea 7 (37%), cough 6 (32%), and phlegm 5 (26%). According to ILO classifications in 2005, among the 36 technicians, 5 (13.8%) had pneumoconiosis. At the end of 7 years, there were 9 pneumoconiosis cases among the 19 remaining technicians (47%). Thus, there was a statistically significant progression on the profusion of the radiologic findings (p < 0.005). Also there was a significant worsening on spirometric findings (p < 0.05). Conclusion: In dental technicians, a determination of both radiologic and functional progressions at the end of 7 years demonstrate that the primary and secondary preventive measures are necessary for these workplaces. Workplaces must be regularly controlled for worker health and hygiene

workers

Background: While the prevalence of byssinosis is decreasing in industrialized countries and persists at high levels in developing countries, this prevalence is remaining constant in Turkey. Objective: In order to determine the effects of past cotton dust exposure on the respiratory tract, a total of 223 persons working in a cotton mill were included in this study. Methods: A questionnaire was used to inquire about respiratory symptoms. Participants underwent several spirometric measurements, which were performed on the 1st, 3rd and 5th day of the working week. Cotton dust measurements were performed in different divisions of the factory. Results: The most common respiratory symptom was chest tightness (20.3%). The prevalence of byssinosis was 14.2% in cotton-processing workers. Among these cases, 28.6% had symptoms on the 1st day of the week, and 71.4% had symptoms on all days of the week. An acute effect was seen in 53.6% of the workers with byssinosis. Mean respirable dust levels were between 0.095 and 0.413 mg/m(3). Conclusions: In spite of technological improvements, respirable dust concentrations are still above the permissible limits, and thus the risk of byssinosis remains. Workers in the cotton industry where obsolete technology is used and standardized protection measures are not applied should be followed for byssinosis. Copyright (C) 2002 S. Karger AG, Basel

without hypertension

QT interval dispersion (QTd) reflects inhomogeneity of repolarisation. Delayed cardiac repolarisation leading to the prolongation of the QT interval is a well-characterised precursor of arrhythmias. Obstructive sleep apnoea syndrome (OSAS) can cause cardiovascular complications, such as arrhythmias, myocardial infarction, and systemic and pulmonary hypertension. The aim of this study was to assess QTd in OSAS patients without hypertension.A total of 49 subjects without hypertension, diabetes mellitus, any cardiac or pulmonary diseases, or any hormonal, hepatic, renal or electrolyte disorders were referred for evaluation of OSAS. An overnight polysomnography and a standard 12-lead ECG were performed in each subject. According to the apnoea-hypopnoea index (AHI), subjects were divided into control subjects (AHI = 15, n = 29). QTd (defined as the difference between the maximum and minimum QT interval) and QT-corrected interval dispersion (QTcd) were calculated using Bazzet's formula.In conclusion, the QTcd was significantly higher in OSAS patients (56.1 +/- 9.3 ms) than in controls (36.3 +/- 4.5 ms). A strong positive correlation was shown between QTCd and AHI. In addition, a significantly positive correlation was shown between QTCd and the desaturation index (DI). The AHI and DI were significantly related to QTCd as an independent variable using stepwise regression analysis.The QT-corrected interval dispersion is increased in obstructive sleep apnoea syndrome patients without hypertension, and it may reflect obstructive sleep apnoea syndrome severity.C1 Pamukkale Univ, Fac Med, Dept Cardiol, Denizli, Turkey.Pamukkale Univ, Fac Med, Dept Chest Dis, Denizli, Turkey