Efficacy and safety of tai chi exercise on bone health: An umbrella review.

PURPOSE: To critically evaluate systematic reviews (SRs) of the Tai Chi (TC) exercise on bone health and provide more recently available evidence. METHODS: SRs with or without meta-analysis (MA) of TC on bone health were comprehensively searched in eight electronic databases (PubMed, EMBASE, Cochrane Library, Web of Science, China National Knowledge Infrastructure, Wanfang Database, Chinese Biomedical Literature Database, and Chinese Scientific Journals Database) and in the international prospective register of systematic reviews of (PROSPERO) from initiation to March 2023. Descriptive analyses of SRs were performed, and reporting and methodological quality of the included SRs were evaluated using the updated version of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist and A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR-2). The certainty of the synthesized evidence was assessed with the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. RESULTS: Eighteen SRs, 15 with MAs, were included. Forty-nine RCTs and 16 NRSIs with 3956 and 1157 participants, respectively, were included in these SRs. The reporting quality of the included SRs ranged from high to low, but most received critically low AMSTAR-2 scores. Efficacy of TC on nine bone health biomarkers has been explored, covering bone mineral density (BMD) and serum biomarkers. The results showed that compare to non-intervention, perimenopausal and postmenopausal participants who practiced TC may benefit in BMD of the lumbar spine [MD = 0.04, 95% CI (0.02, 0.07)], and femoral neck [MD = 0.04, 95% CI (0.02, 0.06)], but not BMD of the femoral proximal trochanter [MD = 0.02, 95% CI (0.00, 0.03)], ward's triangle [MD = 0.02, 95% CI (-0.01, 0.04)], and femoral shaft [SMD = 0.16, 95% CI (-0.11, 0.44)]. Elders practicing TC may benefit in BMD of the femoral neck [SMD = 0.28, 95% CI (0.10, 0.45)], femoral proximal trochanter [SMD = 0.39, 95% CI (0.05, 0.73)], and ward's triangle [SMD = 0.21, 95% CI (0.05,0.37)], but may not in BMD of lumbar spine [SMD = 0.03, 95% CI (-0.22, 0.27)]. CONCLUSION: We have low certainty that for perimenopausal and postmenopausal women, compare to those with no exercise, TC could improve BMD of the lumbar spine, femoral neck. We also have low certainty that in elder population, TC practitioners may benefit in BMD of femoral neck, and Ward's triangle. REGISTRATION: PROSPERO (CRD42020173543).

The association between blood pressure control and long-term cardiovascular outcomes in Hypertension coexistent with obstructive sleep apnea.

PURPOSE: The goal of blood pressure (BP) control will be lower when hypertensive patients have comorbidities that can affect the risk of cardiovascular diseases. But, the goal of BP control for hypertensive patients coexistent with obstructive sleep apnea (OSA) is not discussed, which is a special population at high risk of cardiovascular diseases. PATIENTS AND METHODS: Using data from a retrospective study(Urumqi Research on Sleep Apnea and Hypertension (UROSAH) study, we enrolled 3267 participants who were diagnosed with hypertension and performed polysomnography during 2011-2013 to explore the association between BP control and long-term major adverse cardiovascular and cerebrovascular event (MACCE). Outcomes of interest was the levels of BP control, MACCE, cardiac event and cerebrovascular event. Then we calculated the cumulative incidence of MACCE and performed Cox proportional hazards with stepwise models. RESULTS: 379 of 3267 patients experienced MACCE during a median follow-up of 7.0 years. After full risk adjustment, BP control of 120-139/80-89mmHg was associated with the lowest risk of cerebrovascular event (HR: 0.53, 95%CI:0.35-0.82) rather than MACCE and cardiac event in the total cohort. The association did not change much in patients with OSA. When the SBP and DBP were discussed separately, the SBP control of 120-139mmHg or < 120mmHg was associated with the decreased incidence of MACCE and cerebrovascular event. When DBP control < 80 mm Hg, the risk of cerebrovascular event showed 54% decrease [(HR:0.46, 95%CI: 0.25-0.88)] in patients with hypertension and OSA. CONCLUSION: In this retrospective study, antihypertensive-drug-induced office and home BP control at 120-139/80-89mmHg showed possible beneficial effect on incident MACCE. However, current results need to be verified in future studies.

Alterations in Amygdala/Hippocampal Volume Ratios in Children with Obstructive Sleep Apnea Syndrome Caused by Adenotonsillar Hypertrophy.

BACKGROUND Intermittent hypoxemia can cause changes in certain brain structures. However, in pediatric patients with obstructive sleep apnea (OSA) caused by adenotonsillar hypertrophy (ATH), there is only limited information on the effect of ATH-induced OSA on brain structures. This study sought to investigate alterations in amygdala and hippocampal volumes in children with OSA by ATH. MATERIAL AND METHODS Magnetic resonance imaging scans were applied in children who had ATH-induced OSA (ATH/OSA) and in healthy children. Amygdala and hippocampus volumes and adenoid sizes were measured on MRI volumetric images. The ratio of adenoid size/nasopharyngeal depth was used to describe the severity of adenoid hypertrophy. The clinical variables of the involved subjects were investigated. RESULTS One hundred ATH/OSA children and 100 healthy children without ATH/OSA participated in the study. The ATH/OSA children had higher amygdala volumes and amygdala/hippocampus volume ratios but lower hippocampus volumes than healthy controls, and the amygdala/hippocampus volume ratios were correlated with disease duration and hypoxemia conditions. However, our data showed that amygdala/hippocampus volume ratios were not correlated with the ratios of adenoid size/nasopharyngeal depth in the ATH/OSA children. In addition, the ratio of adenoid size/nasopharyngeal depths in ATH/OSA children was higher than that in healthy children in each subgroup based on the age of participants. CONCLUSIONS Compared to healthy controls, amygdala/hippocampus volume ratios are increased in children with ATH/OSA.

Body roundness index improves the predictive value of cardiovascular disease risk in hypertensive patients with obstructive sleep apnea: a cohort study.

BACKGROUND: Obesity, especially visceral obesity, plays an important role in the progression of cardiovascular disease (CVD). The body roundness index (BRI) is a new measure of obesity that is considered to reflect visceral obesity more comprehensively than other measures. This study aims to evaluate the relationship between BRI and CVD risk in hypertensive patients with obstructive sleep apnea (OSA) and explore its superiority in predicting CVD. METHODS: The Cox proportional hazards model was used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for incident CVD. The area under the curve (AUC), continuous net reclassification improvement (NRI), and integrated discrimination improvement (IDI) were used to assess which measures of obesity had the best predictive value for CVD risk. RESULTS: During a median follow-up period of 6.8 years, 324 participants suffered a CVD event. After multivariable adjustment, compared with the reference group (the first tertile), the HRs (95% CI) of CVD were 1.25 (95% CI, 0.93-1.70) and 1.74 (95% CI, 1.30-2.33) for subjects in the tertile 2 and tertile 3 groups, respectively. Compared with other measurement indicators, BRI has the highest predictive value for CVD risk [AUC: 0.627, 95% CI: 0.593-0.661]. The addition of the BRI to the fully adjusted multivariate model improved the predictive power for CVD, which was validated in the continuous NRI and the IDI (all P < .05). CONCLUSIONS: BRI was significantly associated with the risk of CVD in hypertensive patients with OSA. Furthermore, BRI may improve CVD risk prediction in hypertensive patients with OSA.

[Effects of Obstructive Sleep Apnea and Gender on Glomerular Filtration Rate in Hypertensive Population].

Objective To explore the associations of obstructive sleep apnea(OSA) and gender with estimated glomerular filtration rate(eGFR) in hypertensive populations.Methods From February 2005 to August 2010,2064 hypertensive patients who were treated in the Department of Hypertension Center underwent overnight polysomnographic monitoring.According to the apnea-hypopnea index(AHI),they were assigned into an hypertension combined with OSA group and a hypertension group.The clinical characteristics and sleep monitoring indicators were compared between different genders and between the two groups.Multivariate Logistic regression was employed to analyze the influencing factors of eGFR.Results Among the 2064 hypertensive patients,there were 1537 males(including 1221 patients with OSA) and 527 females(including 350 patients with OSA).The males had higher prevalence of OSA(χ2=36.631,P<0.001) and diastolic blood pressure(Z=-7.776,P<0.001) and lower eGFR(Z=-3.010,P=0.003) than the females.The males had higher AHI(Z=-8.727,P<0.001),apnea index(Z=-9.252,P<0.001),hypopnea index(HI)(Z=-4.868,P<0.001) than the females,and the lowest oxygen saturation(t=-3.325,P=0.001) was significantly lower in males than in females.The hypertension combined with OSA group showed lower eGFR than the hypertension group(Z=-27.434,P<0.001;Z=-18.762,P<0.001).HI was negatively correlated with eGFR in the male population(r=-0.006,P=0.017),and AHI and HI were negatively correlated eGFR in females(r=-0.108,P=0.013;r=-0.094,P=0.032).After adjustment,Logistic regression showed that OSA and oxygen desaturation index 4 were the risk factors for the reduction of eGFR in hypertensive patients in males and females,respectively(OR=1.383,95%CI=1.010-1.905,P=0.045;OR=1.013,95%CI=1.002-1.024,P=0.021).Conclusion OSA lowers the eGFR of hypertensive patients,and OSA and oxygen desaturation index are the risk factors for the decrease in eGFR in male and female hypertensive patients,respectively.

Effect of galectin-3 in the pathogenesis of arteriovenous fistula stenosis formation.

OBJECTIVE: This study sought to investigate the effect of local expression of galectin-3 in the development of stenotic arteriovenous fistula (AVF). METHODS: We collected stenotic venous tissues, adjacent nonstenotic venous tissues, and blood samples from end-stage renal disease (ESRD) patients with AVF stenosis, while normal venous tissues and blood samples were collected from ESRD patients before AVF creation as controls. Also blood samples were collected from ESRD patients with nonstenosis functional AVF. Galectin-3, proliferating cell nuclear antigen (PCNA), matrix metalloproteinase-9 (MMP-9), and α-SMA expression in the venous tissues were examined by immunohistochemistry, and the ERK1/2 pathway activity in the intima was accessed by western blot. Serum galectin-3 level was measured by ELISA. Thereafter, human pulmonary arterial smooth muscle cells (HPASMCs) were cultured in vitro, and the interaction between Galectin-3 and ERK1/2 pathway in HPASMCs was estimated by western blot. RESULTS: ESRD patients with stenotic AVF had a significant higher serum galectin-3 level than normal controls, and patients with non-stenotic functional AVF. The expression levels of galectin-3, phosphorylated ERK1/2, PCNA, MMP-9, and α-SMA in the stenotic venous tissues were higher than that in the normal venous tissues or the adjacent nonstenotic AVF venous tissues. Correlation analysis showed that the expression of galectin-3 of the neointima was positively correlated with PCNA and α-SMA in the stenotic AVF venous tissues. In HPASMCs, galectin-3 can increase the activity of phosphorylated ERK1/2 and promote the expression of α-SMA. CONCLUSION: In the stenotic AVF of ESRD patients, expression of the galectin-3 was significantly increased, showing a positive relation with neointima development.

Prevalence, awareness, treatment and control of hypertension in various ethnic groups (Hui, Kazakh, Kyrgyz, Mongolian, Tajik) in Xinjiang, Northwest China.

Purpose: Credible data is scarce in representative population aged ≥18 years, though hypertension is highly prevalent and poorly controlled in population aged ≥30 years in Xinjiang Northwest China. Therefore, we tried to provide data on hypertension status for reference.Materials and methods: We conducted a population-based cross-sectional survey between 2014 and 2015 using stratified multi-stage random sampling as part of a national survey. Hypertension is defined as systolic blood pressure (BP) ≥140 mmHg, and/or diastolic BP ≥90 mmHg and/or taking anti-hypertensive agents. We assessed prevalence, awareness, treatment and control rates of hypertension by rural and urban regions, by gender and by ethnicity, and related factors including agent prescription pattern.Results: Data for 6807 subjects ≥18 years with 79.2% rural and 52.0% women subjects are analyzed. Overall age-adjusted prevalence of hypertension in population aged ≥18 years is 22.2%, and shows no disparity between genders and regions. By ethnicity, the prevalence of hypertension was the highest in Tajik subjects (25.4%), followed by Mongolian (25.3%) and Kazakh (24.8%) subjects and the lowest in Kyrgyz (20.2%) subjects. Of the hypertensives, 55.5% have awareness, 43.9% receive anti-hypertensive treatment, whereas only 14.5% have their BP controlled. In different ethnic groups, the awareness, control and control in treatment rates showed no significant disparities, except for the treatment rate. It was the highest in Kazakh subjects (50.0%) and the lowest in Hui subjects (36.7%). The most common prescribed agent encompassed ACEI/ARBs (41.1%) and calcium channel blockers (30.4%). Over 87.2% of hypertensives were prescribed for single drug regimen.Conclusions: Hypertension is moderately prevalent in Xinjiang, whereas poorly controlled. Standardization of its treatment such as introducing treatment algorithm might be the priorities for future improvement, with healthy life promotion.

Transfection of Sox11 plasmid alleviates ventilator-induced lung injury via Sox11 and FAK.

Background Ventilator-induced lung injury (VILI) is the most common complication in the mechanical ventilation in clinic. The pathogenesis of VILI has not been well understood. The SRY related High Mobility Group box group-F family member 11(Sox11) is a protein associated with lung development. The focal adhesion kinase(FAK) is a cytoplasmic tyrosine kinase and is regulated by Sox11. The present study, therefore, was undertaken to explore the potential role of Sox11 and FAK in VILI. Methods High volume mechanical ventilation(HMV) was used to establish mouse VILI model under anesthesia. The lung injury was evaluated by analyzing the lung weight, bronchoalveolar lavage fluid, histopathological changes and apoptosis of the lung. The Sox11 and FAK expressions in the lung were investigated by real-time qPCR, western blot and immunohistochemistry analysis. Results HMV induced VILI simultaneously companied with decreased expressions of Sox11 and FAK in alveolar epithelial and interstitial cells either in gene and protein levels. Transfection of Sox11 plasmid significantly upregulated expressions of Sox11 and FAK in gene and protein levels in the lung and particularly effectively alleviated VILI. Furthermore, FAK antagonism by PF562271(FAK antagonist) blocked the alleviating effect of Sox11 plasmid transfection on the VILI. Conclusion The dysregulation in the Sox11 and FAK after HMV play an important role in the pathogenesis of VILI, and facilitating the activity of Sox11and FAK might be an effective target and potential option in the prevention and treatment of VILI in clinic.

Serum lysosomal-associated membrane protein-2 levels are increased in small and medium-vessel vasculitis, especially in polyarteritis nodosa.

OBJECTIVES: Lysosomal-associated membrane protein-2 (LAMP-2) is a highly glycosylated type I glycoprotein ex- pressed on the membranes of neutrophils, endothelial cells and other cells, which are closely linked to subsets of systematic vasculitis. The aim of this study was to investigate whether serum LAMP-2 can be used as a biomarker in small and medium vessel vasculitis (SMVV). METHODS: Serum samples from 39 patients with SMVV (including ANCA-associated vasculitis (AAV) and polyarteritis nodosa (PAN)) confirmed by angiography and/or biopsy and 78 healthy controls (HC) were collected. Serum LAMP-2 levels were determined by enzyme-linked immunosorbent assay. RESULTS: Serum LAMP-2 levels in SMVV patients were increased compared with HC (p<0.001). Serum LAMP-2 levels were significantly different between patients with active stage and those with inactive stage (p=0.024). Patients with renal involvement had higher LAMP-2 levels than patients with non-renal involvement at presentation (p=0.022). Furthermore, serum LAMP-2 levels were correlated with Birmingham Vasculitis Activity Score (BVAS), C-reactive protein (CRP), hypersensitive CRP (Hs-CRP), serum creatinine (Scr) and 24-hour proteinuria (all p<0.05). Among SMVV subsets, serum LAMP-2 levels were signi cantly higher in PAN compared with AAV (p=0.003). In PAN patients, serum LAMP-2 levels were correlated with BVAS and Hs-CRP (all p<0.05). CONCLUSIONS: Serum LAMP-2 levels can reflect the disease activity and renal involvement of SMVV. Furthermore, serum LAMP-2 levels were significantly higher in PAN compared with AAV, and associated with disease activity. LAMP-2 might be a potential biomarker for SMVV, especially in PAN.

Trends in Lipids and Lipoproteins Among Adults in Northwestern Xinjiang, China, From 1998 Through 2015.

BACKGROUND: To examine trends in serum lipids in population in Northwestern Xinjiang between 1998 and 2015 and to provide clues for future prevention. METHODS: We enrolled 5,142 adults aged ≥30 years from seven independent cross-sectional studies conducted in 1998-2000, 2007-2008, and 2015. Blood lipid profiles, such as total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), were measured. RESULTS: The mean age was 48.5 years in 1998-2000, 47.9 years in 2007-2008, and 53.7 years in 2015. There was a declining trend in the prevalence of dyslipidemia among adults in northwestern Xinjiang. Mean LDL-C decreased during the same period, while mean HDL-C showed the opposite trend. Mean TC was 4.79 mmol/L in 1998-2000, 5.17 mmol/L in 2007-2008, and 4.59 mmol/L in 2015. The trend of mean TG was similar to that of TC. The prevalence of dyslipidemia was closely related with male gender, Mongolian ethnicity, hypertension, obesity, elevated fasting blood glucose, smoking, and drinking. CONCLUSION: Between 1998 and 2015, favorable trends in lipid levels have occurred among adults of Northwestern Xinjiang. However, further efforts are needed.

Analysis of key candidate genes and pathways of endometriosis pathophysiology by a genomics-bioinformatics approach.

Endometriosis is a common disease in women, but the signaling pathways and driven genes involved remain unclear. This study integrated four datasets to elucidate potential key candidate genes and pathways in endometriosis. Four expression profile datasets including 29 endometriosis lesions and 37 normal tissues were integrated and analyzed. Differentially expressed genes (DEGs) were sorted, and the gene ontology, pathway enrichment, and protein-protein interaction network of candidate genes were then analyzed. A total of 94 shared DEGs were identified from the four datasets. The DEGs were clustered based on functions and signaling pathways through the analysis of significant enrichment. Among the DEG protein-protein interaction network complex, 87 nodes/DEGs were identified. Furthermore, 18 central node genes were identified, and most of the corresponding genes were involved in the angiotensin system, smooth muscle contraction, cell junction organization, and lipoxin pathways. Through integrated bioinformatic analysis, we identified candidate genes and pathways in endometriosis, which could improve our understanding of endometriosis.

Influences of obstructive sleep apnea on blood pressure variability might not be limited only nocturnally in middle-aged hypertensive males.

PURPOSE: In this cross-sectional study, we analyzed the potential association between sleep measures and blood pressure variability. METHODS: Ninety-three middle-aged hypertensive males, who underwent polysomnography and 24-h ambulatory blood pressure monitoring, were enrolled. Blood pressure variability was assessed by blood pressure standard deviation. Obstructive sleep apnea (apnea hypopnea index ≥ 15) was diagnosed in 52 (55.91%) patients. Mean body mass index and age were 27.77 ± 3.11 kg/m2 and 44.05 ± 8.07 years, respectively. RESULTS: Hypertensive males with obstructive sleep apnea showed significantly higher 24-h, diurnal, and nocturnal diastolic blood pressure variability, compared to those without obstructive sleep apnea. While total cohort was further divided into two groups using the median of oxygen desaturation index, another indicator for severity of OSA, significant differences were also observed in 24-h, diurnal, and nocturnal diastolic blood pressure variability between two groups with higher and lower oxygen desaturation index. While subjects were also divided into two groups via the mean of sleep stage 1, hypertensive males with sleep stage 1 ≥ 8.1% showed significantly higher diurnal diastolic blood pressure variability than those with sleep stage 1 < 8.1%. Apnea hypopnea index was independently associated with 24-h and nocturnal diastolic blood pressure variability; oxygen desaturation index of 3% with 24-h diastolic, diurnal, and nocturnal diastolic blood pressure; and sleep stage 1 was with 24-h and with diurnal diastolic blood pressure variability in all study subjects. CONCLUSION: Effects of obstructive sleep apnea on blood pressure variability may not be limited nocturnally.

Elevated serum concentrations of lipopolysaccharide binding protein might prolong sleep stage one in middle-aged hypertensive males.

PURPOSE: Sleep architecture can be affected by alteration in circulating lipopolysaccaride and cytokines. However, still unknown are the effects of lipopolysaccaride-binding protein (LBP) on sleep architecture. Therefore, potential relationship between alteration in serum LBP concentrations and sleep architecture was analyzed. METHODS: This is a cross-sectional study. Consecutive 54 hypertensive males, aged 30-65 years. and with no obstructive sleep apnea via polysomnography, were recruited. Subjects were divided into two groups via the LBP median as hypertensives with higher and lower serum LBP (n = 27 and n = 27, respectively). Sleep architecture was assessed by polysomnography. Serum LBP, IL-1ß, IL-6, and TNF-α were measured by commercial laboratories using sandwich-type enzyme immunoassay kit. RESULTS: Hypertensive subjects with higher LBP showed significantly higher inflammatory status as assessed by IL-1ß (18.85 ± 3.71 vs 16.15 ± 4.00 ng/L, P = 0.009), IL-6 (67.64 ± 11.22 vs 58.94 ± 11.32 ng/L, P = 0.004), and TNF-α (322.27 ± 59.17 vs 283.89 ± 61.87 pg/ml, P = 0.024) than did those with lower LBP. Hypertensives with higher serum LBP also exhibited prolonged N1 % (7.63 ± 3.55 vs 4.98 ± 2.90 %, P = 0.002), the transition from wakefulness to other sleep stages or follows arousal during sleep, than did those with lower LBP. A significant positive correlation was observed between serum LBP concentrations and N1 % (r = 0.378, P = 0.005) via Spearman's correlation and remained significant even after adjusting for age, apnea-hypopnea index, and body mass index. CONCLUSION: Elevation in serum concentrations of LBP might prolong N1 % in this middle-aged hypertensive males, which needs to be confirmed further.

Association Between Polymorphisms of ADRBK1 Gene and Plasma Renin Activity in Hypertensive Patients: A Case-Control Study.

BACKGROUND Renin is the first step of the RAS cascade, which is a major regulator of salt-volume homeostasis. Adrenergic beta receptor kinase 1 (ADRBK1) plays important roles in regulating blood pressure via the epithelial Na+ channel (ENaC), which plays an important role in Na+ reabsorption in the renal collecting duct. The present case-control study was designed to investigate the potential relationship between polymorphisms of ADRBK1 and plasma renin activity (PRA) in hypertension. MATERIAL AND METHODS We recruited 1831 hypertensive and 422 normotensive Han Chinese subjects. Sitting PRA (ng/mL/h) was measured using radioimmunoassay method. Hypertensive patients were classified into 4 renin categories via PRA quartile. Single-nucleotide polymorphisms (SNPs) of the ADRBK1 gene (rs1894111, rs4930416, rs7127431, rs12286664, and rs3730147) were identified via TaqMan polymerase chain reaction. RESULTS Comparison of the hypertensive group and the control group showed significant differences in distribution of genotypes and alleles of rs1894111 (P<0.05). Moreover, distribution of the dominant model (CC vs. CT+TT) in rs1894111 was lower in the hypertensive group than in the control group (P<0.05). Subjects were classified into 4 subgroups based on PRA quartile; the dominant model (CC vs. CT+TT) of rs1894111 was significantly lower in the quartile 1 group (the group with the lowest PRA) than in the control group (P<0.05). Logistic regression analysis demonstrated that the dominant model (CC vs. CT+TT) of rs1894111 was significantly different in the hypertensive group (OR=1.590, 95%CI=1.022-2.474, P<0.05), particularly in the quartile 1 group (OR=1.845, 95%CI=1.119-3.042, P<0.05), but not in the quartile 4 group. CONCLUSIONS The dominant model (CC vs. CT+TT) of rs1894111 polymorphism in the ADRBK1 gene might be associated with low-renin hypertension in Han Chinese.

Relationship between surfactant proteins B and C and obstructive sleep apnea: is serum SP-B concentration a potential biomarker of obstructive sleep apnea?

BACKGROUND: Surfactant proteins B and C are mainly synthesized, secreted by alveolar type II cells, and affected by hypoxia and mechanical stretches. We hypothesized that their serum levels might be altered by intermittent hypoxia and swing of intrathoracic pressure of obstructive sleep apnea (OSA). METHODS: Consecutive 140 middle-aged males, suspicious of OSA determined by polysomnography, were studied. Surfactant proteins B and C were determined by ELISA. RESULTS: Surfactant protein B (41.39 ± 6.01 vs 44.73 ± 7.62 ng/L, p = 0.005), not C (32.60 ± 6.00 vs 32.43 ± 6.44 ng/L, p = 0.61), significantly lowered in moderate to severe OSA subjects than in non to mild OSA subjects. Severity of OSA is inversely correlated with serum surfactant protein B. Adjusting age, body mass index, and smoking history, compared to subjects with surfactant protein B (SP-B) ≥43.35 ng/L, those with SP-B <43.35 ng/L showed significantly increased 1.528-fold risk for moderate to severe OSA (p = 0.009), whereas no association between surfactant protein C and OSA was observed. Prevalence of moderate to severe OSA in lower SP-B group is higher than that in higher SP-B group (62.7 vs 38.4 %, p = 0.003). Serial and parallel tests on Epworth sleep scale (ESS) and SP-B evaluation can be complementary and prove helpful with high specificity (94.44 %) and sensitivity (84.48 %) to detect moderate to severe OSA. CONCLUSIONS: Serum surfactant protein B, rather than C, is decreased in some individuals with moderate to severe OSA, compared to non to mild OSA subjects. Serum surfactant protein B might be a potential biomarker to diagnose OSA.

What can impulse oscillometry and pulmonary function testing tell us about obstructive sleep apnea: a case-control observational study?

PURPOSE: This study aims to determine whether functional residual capacity (FRC) in obese patients with obstructive sleep apnea (OSA) decreases more than in patients without OSA because of decreased outward recoil from chest wall mass loading as well as increased lung inward recoil. METHODS: Subjects who were overweight and obese to various degrees with normal spirometric values underwent overnight polysomnography to determine the presence or absence of OSA and were labeled as cases or controls. Lung volume and respiratory mechanical properties were measured by plethysmograph and impulse oscillometry, respectively. RESULTS: A total of 76 men and 31 women were diagnosed with OSA (cases); 64 men and 33 women without OSA were confirmed as controls. Expiratory reserve volume and FRC were significantly decreased in cases compared with controls. Respiratory impedance and resistance at 5 Hz were significantly higher in cases than in controls, although reactance at low frequencies was significantly lower in cases than in controls. Reactance at 5 Hz (Xrs5) was found to be independently highly correlated with the severity of OSA as defined by the Apnea-Hypopnea Index and was significantly correlated with FRC. CONCLUSIONS: FRC is significantly decreased in overweight or obese patients with OSA compared with those without OSA, which may be attributed to an increase in lung elastic recoil. The stronger correlation between Xrs5 and OSA severity might indicate upper airway stenosis, and abnormally increased lung elastic recoil may contribute to OSA.

What do changes in concentrations of serum surfactant proteins A and D in OSA mean?

PURPOSE: Previous studies have shown that surfactant proteins are affected by oxygen concentration and mechanic stretches, although the alteration of serum surfactant proteins in individuals with obstructive sleep apnea (OSA) is still unclear. Therefore, the aim of this study is to examine whether serum concentrations of surfactant proteins A and D are altered and related to hypopnea index (HI) in OSA. METHODS: This is a cross-sectional study. Consecutive 140 males, suspicious of OSA, were studied. OSA was determined by PSG and polysomnographic data examined. Subjects with HI ≥ 10.1/h were classified as higher HI group and those with HI < 10.1/h as lower HI group. Hs-CRP, HbA1C, and FBG were determined by standard methods and Krebs von den Lungen-6 (KL-6), surfactant protein-A (SP-A), and surfactant protein-D (SP-D) by ELISA. RESULTS: OSA was diagnosed in 110 patients (78.5%). Mild, moderate, and severe OSA constitutes 26.4, 27.8, and 24.3%, respectively. Mean age was 44.6 ± 7.65 years. Subjects with higher HI had lower SP-A (139.54. ± 32.94 vs 158.2 ± 38.9 ng/L, p = 0.005) and SP-D (16.54 ± 3.67 vs 18.10 ± 3.48 ng/L, p = 0.014) compared to those with lower HI. Nocturnal HI was strongly correlated with serum levels of SP-A (r = 0.343, p = 0.012) and SP-D (r = 0.504, p < 0.001) and are inversely associated with circulating SP-A and SP-D levels, even after adjusting for age and body mass index in nonsmoking subjects. CONCLUSIONS: Circulating SP-A and SP-D levels are decreased in some individuals with higher HI in OSA, possibly reflecting severity of hypoxia in OSA.

Impact of obstructive sleep apnea on lung volumes and mechanical properties of the respiratory system in overweight and obese individuals.

BACKGROUND: Even through narrowing of the upper-airway plays an important role in the generation of obstructive sleep apnea (OSA), the peripheral airways is implicated in pre-obese and obese OSA patients, as a result of decreased lung volume and increased lung elastic recoil pressure, which, in turn, may aggravate upper-airway collapsibility. METHODS: A total of 263 male (n = 193) and female (n = 70) subjects who were obese to various degrees without a history of lung diseases and an expiratory flow limitation, but troubled with snoring or suspicion of OSA were included in this cross-sectional study. According to nocturnal-polysomnography the subjects were distributed into OSA and non-OSA groups, and were further sub-grouped by gender because of differences between males and females, in term of, lung volume size, airway resistance, and the prevalence of OSA among genders. Lung volume and respiratory mechanical properties at different-frequencies were evaluated by plethysmograph and an impulse oscillation system, respectively. RESULTS: Functional residual capacity (FRC) and expiratory reserve volume were significantly decreased in the OSA group compared to the non-OSA group among males and females. As weight and BMI in males in the OSA group were greater than in the non-OSA group (90 ± 14.8 kg vs. 82 ± 10.4 kg, p < 0.001; 30.5 ± 4.2 kg/m(2) vs. 28.0 ± 3.0 kg/m(2), p < 0.001), multiple regression analysis was required to adjust for BMI or weight and demonstrated that these lung volumes decreases were independent from BMI and associated with the severity of OSA. This result was further confirmed by the female cohort. Significant increases in total respiratory resistance and decreases in respiratory conductance (Grs) were observed with increasing severity of OSA, as defined by the apnea-hypopnea index (AHI) in both genders. The specific Grs (sGrs) stayed relatively constant between the two groups in woman, and there was only a weak association between AHI and sGrs among man. Multiple-stepwise-regression showed that reactance at 5 Hz was highly correlated with AHI in males and females or hypopnea index in females, independently-highly correlated with peripheral-airway resistance and significantly associated with decreasing FRC. CONCLUSIONS: Total respiratory resistance and peripheral airway resistance significantly increase, and its inverse Grs decrease, in obese patients with OSA in comparison with those without OSA, and are independently associated with OSA severity. These results might be attributed to the abnormally increased lung elasticity recoil pressure on exhalation, due to increase in lung elasticity and decreased lung volume in obese OSA.

[Association of SOCS3 gene polymorphisms with insulin resistance in Xinjiang Uygur population].

OBJECTIVE: To assess the association of suppressor of cytokine signaling 3 (SOCS3) gene polymorphisms with insulin resistance (IR) in Xinjiang Uygur population. METHODS: A cross-sectional study on metabolic diseases, e.g., obesity, was conducted on ethnic Uygurs in Hetian, Xinjiang of China. A total of 1292 Uygur individuals were enrolled. The sample size for IR subjects [homeostasis model assessment for insulin resistance (HOMA-IR) ≥ 2.96] was 323, whereas that for non-IR controls was 969 (HOMA-IR < 2.96). Representative variations were selected from database and genotyped with TaqMan polymerase chain reaction method. For the relatively isolated population from a homogeneous environment, a case-control study was conducted to assess the association between variations of SOCS3 gene and IR. RESULTS: A significant difference in genotype distribution of rs4969168 was detected between IR and control groups in males (chi square =7.216, P=0.027). Although the IR-related quantitative phenotypes did not significantly differ between individuals with GG, AG and AA genotypes of rs4969168 in the overall, male and female population (P > 0.05), the mean of body mass index and the median of fasting insulin increased in individuals with GG, AG, AA genotypes in males. Haplotype 2 (rs12953258C-rs4969168A-rs9914220C) was significantly associated with a higher prevalence of IR in males (P=0.023). Logistic regression analysis indicated that AG genotype of rs4969168 variation is a protective factor for IR in males (OR=1.772, 95% confidence interval: 1.081-2.906, P=0.023). CONCLUSION: Our study suggested that the rs4969168 polymorphism of SOCS3 gene is associated with IR in ethnic Uygur population from Xinjiang, China.

[Association of GIRK4 gene polymorphisms with essential hypertension in obese ethnics Uygur from southern Xinjiang].

OBJECTIVE: To assess the association of polymorphisms of G protein-coupled inwardly-rectifying potassium channels 4 (GIRK4) gene with essential hypertension in ethnic Uygurs from southern Xinjiang. METHODS: A total of 1194 (461 males and 733 females) Uygur residents aged 30 to 70 and with a body mass index (BMI) over 18.5 kg/m(2) were selected from Hetian region. All of the subjects have received questionnaire survey, physical examination, biochemical analysis and blood pressure measurement. They were divided into hypertensive group and normotensive group. Genotyping by the TaqMan polymerase chain reaction method was performed for 4 common single nucleotide polymorphisms (rs4937391, rs2604204, rs6590357 and rs1122149), and a case-control study was carried out. RESULTS: Genotype distributions of rs4937391, rs2604204, rs6590357 and rs1122149 in both groups were in Hardy-Weinberg equilibrium (P> 0.05). The average systolic blood pressure of CC genotype of rs11221497 single nucleotide polymorphism (SNP)[(132.69± 26.9) mmHg)] was higher than the CG genotype [(127.4± 22.7) mmHg] and GG genotype [(121.1± 26.3) mmHg]. There has a significantly difference in average systolic and diastolic blood pressures between CC and GG genotypes (P< 0.05). A case-control association analysis revealed that the rs11221497 SNP was in association with essential hypertension with the dominant model [P< 0.05, OR= 0.67 (0.49-0.93)]. Haplotype analysis indicated that H6(C-G-C-G) was significantly more common in normotensive group than hypertensive group (P= 0.001). CONCLUSION: The rs11221497 SNP of the GIRK4 gene is associated with essential hypertension in ethnic Uygur population in Xinjiang.