Qi-Chang Lin

Obstructive sleep apnea syndrome is associated with some components of metabolic syndrome in nonobese adults

PurposeThe relationship between obstructive sleep apnea (OSA) syndrome and metabolic syndrome is far from conclusion for obesity as a confounding factor. The aim of the present study was to investigate the association between OSA and some components of metabolic abnormality in nonobese patients.MethodsWe consecutively recruited nonobese subjects who underwent polysomnography and analyzed some components of metabolic abnormality in subjects with and without OSA. Multiple linear regression was used to evaluate the independent risk factor of some components of metabolic abnormality.ResultsA total of 154 subjects were enrolled and were divided to control group (45 subjects) and OSA group (113 subjects). Body mass index was no different between groups. Systolic blood pressure, triglycerides, and insulin concentration were significantly higher among OSA group compared with control group (p = 0.000, 0.043, and 0.006, respectively), and the prevalences of dyslipidemia, hypertension, and at least two of the metabolic abnormalities were significantly greater in OSA group (p = 0.003, 0.031, and 0.000, respectively). After adjusting for confounding factors, lowest O2 saturation was the major contributing factor for elevated systolic blood pressure (p = 0.001), and independent associations were found between apnea–hypopnea index and the following parameters of metabolic abnormality: triglycerides and homeostasis model assessment of insulin resistance (all p = 0.000).ConclusionsOur finding was consistent with previous studies that OSA was independently associated with dyslipidemia, hypertension, and at least two of metabolic abnormalities in nonobese patients.

Bronchoalveolar lavage fluid galactomannan detection for diagnosis of invasive pulmonary aspergillosis in chronic obstructive pulmonary disease

Invasive pulmonary aspergillosis (IPA) is difficult to diagnose in chronic obstructive pulmonary disease (COPD). The aim of this study was to evaluate whether detection of galactomannan (GM) in bronchoalveolar lavage fluid (BALF) might be a useful means of making the diagnosis. Patients with COPD and new pulmonary infiltrates were enrolled. BALF was collected for culture and detection of GM. Venous blood was also sampled for GM detection. Biopsy samples were obtained whenever possible. Eleven cases of IPA were diagnosed (three proven and eight probable); 80 controls without IPA diagnosed were recruited. At a GM cut-off of 0.5, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for diagnosing IPA were 90.9, 66.3, 27.0 and 98.1% in serum, and 90.9, 62.5, 25.0 and 98.0% in BALF, respectively. At a cut-off of 1.0, the specificity, PPV and NPV in BALF increased to 95.0, 71.4 and 98.7%; the sensitivity remained 90.9%. The sensitivity in serum was substantially lower than BALF (45.5% versus 90.9%). Receiver operating characteristic curve analysis identified an optimal BALF GM cut-off value of 1.25, with a sensitivity of 90.9% and a specificity of 96.3% for diagnosing IPA. At a relatively high cut-off value, BALF GM detection is a useful tool for the diagnosis of IPA in COPD. Besides piperacillin-tazobactam and amoxicillin-clavulanate, many other factors may also cause false-positive of GM detection in patients without IPA. Further work is needed to identify factors that might lead to false-positive or false-negative results.

The relationship between excessive daytime sleepiness and metabolic syndrome in severe obstructive sleep apnea syndrome

Excessive daytime sleepiness (EDS), which is commonly considered a cardinal sign of obstructive sleep apnea (OSA), may lead to an increased rate of metabolic syndrome (MetS), and be an independent risk factor for cardiovascular morbidity and mortality. The aim of this cross‐sectional study was to examine the role of EDS in MetS and its components by researching severe OSA patients.

Relationship between obstructive sleep apnea and nonalcoholic fatty liver disease in nonobese adults

PurposeObstructive sleep apnea (OSA) is closely related to nonalcoholic fatty liver disease (NAFLD), though the mechanism is not conclusive as obesity is a confounder. The objective of this observational study was to investigate the correlation between these disorders in nonobese subjects.MethodsWe consecutively enrolled nonobese individuals undergoing polysomnography and abdominal ultrasonography and analyzed differences in NAFLD patients grouped by the apnea–hypopnea index (AHI) and in OSA patients according to the presence or absence of NAFLD. Multivariate regression analysis was used to evaluate the independent risks of NAFLD in OSA patients.ResultsA total of 175 participants were included. The 106 ultrasound-diagnosed NAFLD patients were classified into four groups by AHI. There were no significant differences in triglycerides (TG), serum aminotransferase levels of alanine aminotransferase and aspartate aminotransferase, high-sensitivity C-reactive protein, and homeostasis model assessment of insulin resistance (HOMA-IR) with worsening OSA. In both OSA patients with NAFLD and those without NAFLD, body mass index (BMI), the lowest oxygen saturation (LaSO2), HOMA-IR, and TG were significantly associated. Additionally, BMI, LaSO2, and TG independently predicted the development of NAFLD after adjustments (odds ratio [OR] = 1.562, p = 0.003; OR = 0.960, p = 0.03; OR = 3.410, p < 0.001, respectively).ConclusionsIn nonobese subjects, OSA itself does not appear to induce significant changes in liver enzymes. With reference to lipid metabolism, weight control and OSA-related hypoxemia are key factors in reducing the risk of NAFLD in OSA patients. Additional large-scale, prospective studies are warranted to investigate the impact of OSA on liver injury in nonobese adults.

Detection and analysis of apoptosis- and autophagy-related miRNAs of mouse vascular endothelial cells in chronic intermittent hypoxia model

ABSTRACT Endothelial dysfunction is the main pathogenic mechanism of cardiovascular complications induced by obstructive sleep apnea/hyponea syndrome (OSAHS). Chronic intermittent hypoxia (CIH) is the primary factor of OSAHS‐associated endothelial dysfunction. The hypoxia inducible factor (HIF) pathway regulates the expression of downstream target genes and mediates cell apoptosis caused by CIH‐induced endothelial injury. miRNAs play extensive and important negative regulatory roles in this process at the post‐transcriptional level. However, the regulatory mechanism of miRNAs in CIH tissue models remains unclear. The present study established a mouse aortic endothelial cell model of CIH in an attempt to screen out specific miRNAs by using miRNA chip analysis. It was found that 14 miRNAs were differentially expressed. Of them, 6 were significantly different and verified by quantitative real‐time PCR (Q‐PCR), of which four were up‐regulated and two were down‐regulated markedly. To gain an unbiased global perspective on subsequent regulation by altered miRNAs, we established signaling networks by GO to predict the target genes of the 6 miRNAs. It was found that the 6 identified miRNAs were apoptosis‐ or autophagy‐related target genes. Down‐regulation of miR‐193 inhibits CIH induced endothelial injury and apoptosis‐ or autophagy‐related protein expression. In conclusion, our results showed that CIH could induce differential expression of miRNAs, and alteration in the miRNA expression pattern was associated with the expression of apoptosis‐ or autophagy‐related genes.

Applicability of visceral adiposity index in predicting metabolic syndrome in adults with obstructive sleep apnea: a cross-sectional study

BackgroundObstructive sleep apnea (OSA) is severely affected by visceral adiposity (VA) that correlates to another disorder—metabolic syndrome (MetS). However, little is known concerning the relation of visceral adiposity index (VAI)—a novel and simple indicator of VA, with OSA and MetS. The objective of the study was to analyze the association of VAI with both disorders and applicability to identify OSA patients at risk of MetS.MethodsConsecutive individuals undergoing polysomnography and biochemical tests were enrolled, and differences in all subjects grouped by apnea-hypopnea index (AHI) were analyzed. Spearman correlation was performed for assessing the relationship between VAI, OSA-related indices and metabolic score—total number of the positive diagnostic criteria of MetS. Receiver operating characteristic (ROC) curve was conducted to obtain a cut-off value of VAI for predicting incident MetS by sex. Then, the risk of MetS in OSA patients according to the cut-offs was attained by logistic regression.ResultsA total of 411 individuals were enrolled. Of whom, 361 subjects were diagnosed OSA (mild in 67 patients, moderate in 89 and severe in 205, respectively). A significant increasing trend based on AHI was observed in the variables of blood pressure, triglycerides, fasting glucose, incident MetS, metabolic score and VAI (all p < 0.05). Irrespective of gender, VAI was all significantly correlated with PSG characteristics as AHI, mean nocturnal oxygen saturation, the lowest oxygen saturation, metabolic score(all p < 0.05). A VAI of 2.282, 2.105, 2.511 (for all subjects, males and females, separately) were calculated to determine the occurrence of MetS. According to the cut-offs, OSA patients tended to suffer from greater risk in MetS (odds ratio [OR] = 10.237, p = 0.000; OR = 13.556, p = 0.000; OR = 21.458, p = 0.000).ConclusionsThe present study suggested that VAI was significantly associated with MetS and OSA. As a simple and alternative approach obtained in everyday practice, it may offer a powerful tool to identify patients with OSA at risk of MetS.

Obstructive sleep apnea is associated with fatty liver index, the index of nonalcoholic fatty liver disease.

Background and objectives The relationship between obstructive sleep apnea (OSA) and nonalcoholic fatty liver disease (NAFLD) is gaining increased attention. The aim of the present study was to examine the relationship of OSA with NAFLD defined by an elevated fatty liver index (FLI). Materials and methods A total of 319 consecutive patients who underwent standard polysomnography were enrolled. Fasting blood samples were obtained from all patients for biological profile measurements, and demographic data were collected. Values of FLI were determined and assessed as predictors of the presence of NAFLD, as measured by ultrasound. The discriminative ability of FLI was estimated on the basis of the area under the receiver operator characteristic curve. Results An FLI of 60 achieved the highest diagnostic accuracy and yielded an area under the receiver operator characteristic curve of 0.822 (95% confidence interval: 0.729–0.916) in the detection of NAFLD. Patients with an FLI of 60 or higher had a significantly lower lowest O2 saturation (73 vs. 83%, P<0.001), a lower mean nocturnal oxygen saturation (93 vs. 95%, P<0.001), a higher apnea–hypopnea index (39.7 vs. 18.4, P<0.001), a higher oxygen desaturation index (39 vs. 10.6, P<0.001), and a higher percentage of sleep time spent with SpO2 less than 90% (4.63 vs. 0.92%, P<0.001) compared with those with FLI less than 60. In multivariate analysis, the presence of OSA was independently associated with elevated FLI after adjusting for confounding factors (odds ratio: 5.141, 95% confidence interval: 1.414–18.696, P=0.013). Conclusion Our results suggest a positive association between the severity of OSA and NAFLD defined by an elevated FLI, which may serve as a good biomarker for detecting NAFLD in OSA patients.

Role of FoxO1 and apoptosis in pulmonary vascular remolding in a rat model of chronic thromboembolic pulmonary hypertension

To explore the role of FoxO1 and apoptosis in a rat model of chronic thromboembolic pulmonary hypertension (CTEPH). Rats were randomly divided into a sham group (n = 45) and an experimental group (n = 45). Autologous blood clots were injected into rats three times to induce CTEPH. Rats were further divided into three subgroups: a 1-week subgroup (n = 15), a 2-week subgroup (n = 15), and a 4-week subgroup (n = 15). Mean pulmonary arterial pressure (mPAP) and histopathology were evaluated at each time point. FoxO1, Bad, and Bcl-2 levels were examined at each time point using reverse transcription PCR and western blotting. The mPAP and vessel wall area/total area (WA/TA) ratio in the experimental group gradually increased in a time-dependent manner (P < 0.05). Both the mRNA and protein levels of FoxO1 decreased in the CTEPH rats compared to in the sham group. In addition, embolization led to the up-regulation of Bad and the down-regulation of Bcl-2 (P < 0.05). FoxO1 and apoptosis play an important role in the pathogenesis of CTEPH. Apoptosis-resistant pulmonary artery endothelial cells may play an important role in remodeling of the rat pulmonary artery.

Snoring and components of metabolic syndrome in Southeastern Chinese adults: A community-based study

Snoring has been associated with a number of abnormal conditions, but little work has been done on its association with components of metabolic syndrome based on the epidemiology in Chinese adults.

An irregular pulmonary nodule was confirmed diagnosis of aspiration pneumonia by finding plant cells through rapid on-site evaluation

Rapid on‐site evaluation (ROSE) is a method which is often used in quick‐staining cytology in the tumour diagnostic field, and results in a significant decrease in diagnostic time and cost. However, we have not found any previous report on the ROSE method for diagnosing aspiration pneumonia.