Endotypic traits of supine position and supine-predominant obstructive sleep apnoea in Asian patients

BACKGROUND

Over half of all cases of obstructive sleep apnoea (OSA) are classified as supine-related OSA; however, the pathological endotype during supine position is not fully understood. This study aims to investigate the endotypic traits of supine-predominant OSA and explore the variations in endotypic traits between the supine and lateral positions.

METHODS

We prospectively recruited 689 adult patients with OSA from a single sleep centre between April 2020 and December 2022. Endotypic traits, namely arousal threshold, collapsibility, loop gain and upper airway muscle compensation, were retrieved from polysomnographic signals. We identified spOSA by a supine to non-supine apnoea-hypopnoea index (AHI) ratio >2. We cross-sectionally compared demographic and endotypic traits between supine-predominant OSA and non-positional OSA and examined the associations between supine-predominant OSA and endotypic traits. Additionally, we compared the changes in endotypic traits between supine and lateral positions in patients with supine-predominant OSA and non-positional OSA.

RESULTS

In our study sample, 75.8% of patients were identified as having supine-predominant OSA. Compared to non-positional OSA, supine-predominant OSA was associated with low collapsibility (β= -3.46 %eupnoea, 95% CI -5.93- -1.00 %eupnoea) and reduced compensation (β= -6.79 %eupnoea, 95% CI -10.60- -2.99 %eupnoea). When transitioning from the lateral to supine position, patients with supine-predominant OSA had a substantial decrease in compensation compared to those with non-positional OSA (-11.98 versus -6.28 %eupnoea).

CONCLUSIONS

Supine-predominant OSA is the prevalent phenotype of OSA in Asian patients. Inadequate upper airway compensation appears to be a crucial underlying pathology in patients with supine-predominant OSA.

Dose of selective serotonin reuptake inhibitors and risk of upper gastrointestinal bleeding in older adults

BACKGROUND

Selective serotonin reuptake inhibitors (SSRIs) have been associated with an increased risk of upper gastrointestinal bleeding (UGIB) in older patients but little is known about the risk associated with individual SSRI drugs and doses.

AIMS

To quantify the risk of UGIB in relation to individual SSRI use in older adults.

METHODS

We conducted a nested case-control study within a cohort of 9565 patients aged ⩾65 years prescribed SSRIs from 2000 to 2013 using claims data of universal health insurance in Taiwan. Incident cases of UGIB during the follow-up period were identified and matched with three control subjects. Conditional logistic regression was used to estimate the odds ratio (OR) of UGIB associated with individual SSRI use and cumulative dose.

RESULTS

UGIB risk increased with the increasing cumulative doses of SSRIs (adjusted OR: 1.28, 95% confidence interval (CI): 1.02-1.62 for the highest vs. the lowest tertile). Compared with users of other SSRIs, fluoxetine users were at an increased risk of UGIB (adjusted OR: 1.25, 95% CI: 1.03-1.50) with a dose-response manner, whereas paroxetine users had 29% decreased odds (95% CI: 0.56-0.91). The increased risk was only observed among current fluoxetine users.

CONCLUSIONS

Fluoxetine therapy was associated with an increased risk of UGIB in a dose-response manner among older adults.

Recommended assessment and management of sleep disordered breathing in patients with atrial fibrillation, hypertension and heart failure: Taiwan Society of Cardiology/Taiwan Society of sleep Medicine/Taiwan Society of pulmonary and Critical Care Medicine joint consensus statement

Sleep disordered breathing (SDB) is highly prevalent and may be linked to cardiovascular disease in a bidirectional manner. The Taiwan Society of Cardiology, Taiwan Society of Sleep Medicine and Taiwan Society of Pulmonary and Critical Care Medicine established a task force of experts to evaluate the evidence regarding the assessment and management of SDB in patients with atrial fibrillation (AF), hypertension and heart failure with reduced ejection fraction (HFrEF). The GRADE process was used to assess the evidence associated with 15 formulated questions. The task force developed recommendations and determined strength (Strong, Weak) and direction (For, Against) based on the quality of evidence, balance of benefits and harms, patient values and preferences, and resource use. The resulting 11 recommendations are intended to guide clinicians in determining which the specific patient-care strategy should be utilized by clinicians based on the needs of individual patients.

Continuous positive airway pressure and adherence in patients with different endotypes of obstructive sleep apnea

Determining the endotypes of obstructive sleep apnea (OSA) has potential implications for precision interventions. Here we assessed whether continuous positive airway pressure (CPAP) treatment outcomes differ across endotypic subgroups. We conducted a retrospective analysis of data obtained from 225 patients with moderate-to-severe OSA from a single sleep centre. Polysomnographic and CPAP titration study data were collected between May 2020 and January 2022. One-month CPAP treatment adherence was followed. Obstructive sleep apnea endotypes, namely arousal threshold, collapsibility, loop gain, and upper airway gain were estimated from polysomnography and dichotomised as high versus low. We examined associations between endotypic subgroups and (1) optimal CPAP titration pressure, (2) CPAP-related improvements in sleep architecture (proportions of slow-wave and rapid eye movement (REM) sleep), and (3) CPAP adherence. We observed that patients with high collapsibility required a higher CPAP pressure than those with low collapsibility (∆ = 0.4 cmH2 O, 95% confidence interval [CI] = 0.3-1.7). A larger increase in slow-wave sleep and in REM sleep proportions after CPAP treatment were observed in patients with a high arousal threshold, high collapsibility, high loop gain, or high upper airway gain than in those with low levels of endotypes. High loop gain and high collapsibility were independently associated with longer CPAP use hours per night (∆ = 0.6 h, 95% CI = 0.2-1.5 and ∆ = 0.3 h, 95% CI = 0.03-1.5, respectively). In conclusion, different endotypic subgroups of OSA exhibit a difference in outcomes of CPAP treatment. Knowledge of endotypes may help clinicians to understand which patients are expected to benefit most from CPAP therapy prior to its administration.

Relationship between Symptom Profiles and Endotypes among Patients with Obstructive Sleep Apnea: A Latent Class Analysis

Rationale: Obstructive sleep apnea (OSA) is a heterogeneous syndrome with various endotypic traits and symptoms. A link among symptoms, endotypes, and disease prognosis has been proposed but remains unsupported by empirical data. Objectives: To link symptom profiles and endotypes by clustering endotypic traits estimated using polysomnographic signals. Methods: We recruited 509 patients with moderate to severe OSA from a single sleep center. Polysomnographic data were collected between May 2020 and January 2022. Endotypic traits, namely arousal threshold, upper airway collapsibility, loop gain, and upper airway muscle compensation, were retrieved using polysomnographic signals during non-rapid eye movement periods. We used latent class analysis to group participants into endotype clusters. Demographic and polysomnographic parameter differences were compared between clusters, and associations between endotype clusters and symptom profiles were examined using logistic regression analyses. Results: Three endotype clusters were identified, characterized by high collapsibility/loop gain, low arousal threshold, and low compensation, respectively. Patients in each cluster exhibited similar demographic characteristics, but those in the high collapsibility/loop gain cluster had the highest proportion of obesity and severe oxygen desaturation observed in polysomnographic studies. The low compensation cluster was characterized by fewer sleepy symptoms and exhibited a lower rate of diabetes mellitus. Compared with the excessively sleepy group, disturbed sleep symptoms were associated with the low arousal threshold cluster (odds ratio, 1.89; 95% confidence interval, 1.16-3.10). Excessively sleepy symptoms were associated with the high collapsibility/loop gain cluster (odds ratio, 2.16; 95% confidence interval, 1.39-3.37) compared with the minimally symptomatic group. Conclusions: Three pathological endotype clusters were identified among patients with moderate to severe OSA, each exhibiting distinct polysomnographic characteristics and clinical symptom profiles.

Rest-activity rhythm associated with depressive symptom severity and attention among patients with major depressive disorder: a 12-month follow-up study

Introduction

Patients with depressive disorder demonstrate rest-activity rhythm disturbances and cognitive function impairment. This study examined the association of individual rest-activity rhythm changes over time with mood symptoms and attention.

Methods

We recruited 15 adult outpatients with a diagnosis of major depressive disorder from a single medical center and observed them for 12 months. Weekly rest-activity parameters, including rhythm characteristics generated from nonparametric circadian rhythm analysis, were retrieved from actigraphy data. Attention was evaluated weekly with a smartphone-based psychomotor vigilance test upon awakening. Depressive symptom severity was evaluated using the Beck Depression Inventory (BDI) fortnightly. The association of rest-activity parameters with BDI score and attention was examined using generalized linear mixed regression. A fixed-effects analysis was used to examine the association between rest-activity parameters and depressive episodes.

Results

An advanced bedtime and most active continuous 10 h starting time were associated with depressive symptom severity but also associated with higher vigilance test performance. A longer sleep duration, mainly due to an earlier bedtime, was associated with depressive symptom severity. Compared to remission, sleep duration was 27.8 min longer during depressive episodes, and bed time was 24 min earlier. A shorter sleep duration and increased activity during sleep were associated with poorer attention.

Discussion

Rest-activity rhythms change with mood symptoms among patients with depressive disorder. The circadian rhythms of rest-activity among patients with depressive disorder should be distinguished during various mood states in future studies.

The Effectiveness and Tolerability of Glycopyrronium for Patients with Chronic Obstructive Pulmonary Disease in a Clinical Setting: GLARE-Taiwan

Glycopyrronium (GLY) is a pharmacological maintenance treatment for chronic obstructive pulmonary disease (COPD). However, its effectiveness and tolerability for COPD patients in routine clinical practice have not been well-investigated. This study aimed to assess the effectiveness of GLY on health-related quality of life and its safety in patients with COPD in a routine clinical care setting. This multi-center, prospective, six-month observational study recruited patients diagnosed with COPD and treated with GLY at three medical centers in central Taiwan. The full analysis set (n = 102) had a significant improvement in the Clinical COPD Questionnaire total (mean ± SD = −0.39 ± 0.90, p = 0.002), symptoms (mean ± SD = −0.61 ± 0.90, p < 0.001) and mental state scores (mean ± SD = −0.54 ± 1.72, p = 0.021) but not the functional state score (mean ± SD = −0.10 ± 1.15, p = 0.529). During the observational period, 58 patients (52.73%) experienced adverse events; only one adverse event (dizziness) was suspected to be related to the study drug. Three patients (2.73%) discontinued the study and GLY treatment because of an adverse event. One patient (0.91%) died during the study period because of a cerebral infarction, which was judged to be not associated with GLY treatment. In conclusion, GLY could be effective in improving the health status and is safe for patients with COPD in a real-life setting.

Impact of sleep timing on attention, sleepiness, and sleep quality among real-life night shift workers with shift work disorder: a cross-over clinical trial

STUDY OBJECTIVES

To examine the effect of sleep timing intervention on sleep quality, attention, and sleepiness at work among night shift workers with shift work disorder.

METHODS

We recruited 60 real-life night shift workers through advertisements to participate this cross-over clinical trial. Shift work disorder was confirmed with interview and sleep log. Participants were designated to follow evening sleep (15:00-23:00) and morning sleep (09:00-17:00) schedules in a randomized order. Chronotype was confirmed by the Munich Chronotype Questionnaire. Sleep behaviors and light exposure were recorded using actigraphy. Outcome measures were sleepiness evaluated by the Karolinska Sleepiness Scale, sleep quality evaluated by the Pittsburgh Sleep Quality Index, and attention performance assessed with psychomotor vigilance test. Differences in outcome between the morning and evening sleep schedules were compared using repeated measures ANOVA.

RESULTS

The participants slept for longer durations during evening sleep schedules compared with morning sleep schedules. Lower sleepiness scores, higher sleep quality, and shorter reaction times and less lapse numbers in the psychomotor vigilance test were observed for participants during evening sleep schedules than morning sleep schedules after adjustment for light exposure and sleep duration. Significant interaction effects were observed for reaction time and lapse number between chronotype and sleep schedule, where the differences between sleep schedules were most prominent among those with late chronotypes.

CONCLUSIONS

It is recommended that night shift workers with shift work disorder arrange to sleep in the evening instead of the morning for better sleep and attention performance, especially those with late chronotypes.

TRIAL REGISTRATION

Sleep Schedule Intervention Study Among Night Shift Workers, https://clinicaltrials.gov/ct2/show/NCT04160572, ClinicalTrials.gov Identifier: NTC04160572.

Polysomnography Is an Important Method for Diagnosing Pediatric Sleep Problems: Experience of One Children’s Hospital

In this study, we collected and analyzed polysomnography (PSG) data to investigate the value of PSG in diagnosing sleep problems in children. The results of PSG studies of children (<18 years old) with sleep problems conducted from April 2015 to May 2017 at a children’s hospital in Taiwan were collected and analyzed retrospectively. Data for 310 patients (209 males and 101 females) who underwent PSG were collected. The final diagnoses were as follows: obstructive sleep apnea in 159 (51.3%), snoring in 81 (26.4%), limb movement sleep disorder in 25 (8.1%), hypersomnias in 12 (3.9%), central apnea in 8 (2.9%), enuresis in 7 (2.3%), bruxism in 5 (1.6%), sleep terrors in 5 (1.6%), narcolepsy in 3 (1.0%), sleep seizures in 3 (1.0%), sleep walking in 1 (0.3%), and insomnia in 1 (0.3%). PSG may help detect significant sleep-related problems in children and is useful for making therapeutic decisions regarding children. Obstructive sleep apnea syndrome (OSAS) was the primary sleep problem for most of the children (51.3%); however, only 7.4% of them underwent surgery for OSAS. We therefore suggest that children with sleep problems should undergo PSG.

Focal conformal fractionated radiotherapy vs. radiosurgery for lung cancer patients with limited brain metastases

BACKGROUND

For lung cancer (LC) patients with limited brain metastases (LBM), radiosurgery (RS) was the current preferred strategy. We aimed to report our experience regarding an alternative strategy (focal conformal fractionated radiotherapy, FCFRT) for these patients in this cohort study.

METHODS

We identified LC patients with LBM treated with either FCFRT or RS within 2016-2019 without prior brain local treatment via in-house databases. The characteristics of patients, disease, treatment, and outcome were retrospectively obtained via chart review and peer review. The 1st day of FCFRT or RS was the index date. Overall survival (OS) was calculated from the index date to the last date of contact or death via the Kaplan-Meier method. Log-rank test was used in univariate analyses (UVA) whereas Cox regression method was used in the multivariate analyses (MVA). The incidence of local progression (LP) or distal brain metastases (DBM) was estimated by the competing risk approach with death as the competing risk.

RESULTS

We identified 23 eligible patients. The median dose/fractionation for FCFRT was 36 Gy/10 fractions. The median dose for RS was 20 Gy. The Lung-molGPA prognostic groups' distribution for these two groups was not statistically different. After a median follow-up of 8 months (range, 1-38 months), the OS was not statistically different in UVA [P value 0.9]. The adjusted hazard ratio of death was 0.96 when FCFRT was compared to RS in MVA (95% CI, 0.21-5.22). There was also no statistical significant difference in LP (P value 0.79) or DBM (P value 0.88).

CONCLUSIONS

For LC patients with LBM, the OS was not statistically different for definitive FCFRT or RS. There was also no statistical difference in LP or DBM. Further studies should be considered to clarify the indication of FCFRT.

A follow-up study on restless legs syndrome in chronic obstructive pulmonary disease population

BACKGROUND

Restless legs syndrome (RLS) is prevalent in patients with chronic obstructive pulmonary disease (COPD). No large population-based cohort study has assessed the relationship. We evaluated the incidence of RLS among COPD patients by sociodemographic status (SES) and comorbidity using insurance claims data of Taiwan.

METHODS

From the database, we established a cohort consisting of 77,831 individuals aged ≥ 20 years newly diagnosed with COPD from 2000 to 2013. We also identified same number of individuals without COPD as the comparison cohort, frequency matched by sex, age and index year. Both cohorts were followed up to the end of 2013 to estimate the incidence and hazard ratio (HR) of developing RLS.

RESULTS

The incidence of RLS was 2.2-fold higher in COPD patients than in those free of COPD (6.67 and 3.08 per 10,000 person-years), with an adjusted HR (aHR) 1.68 (95% CI 1.41-2.01) after controlling for covariates. The incidence rates in both cohorts increased with age and higher in low socioeconomic group. The risk of RLS increased further among COPD patients with additional comorbidities. Compared to those without COPD and comorbidity, the aHR was 7.93 (95% CI 1.11-57.8) for those with iron deficiency, 3.95 (96% CI 1.92-8.13) with Parkinson's disease, 2.85 (95% CI 1.05-7.72) with polyneuropathy, or 1.81 (95% CI 1.14-2.87) with diabetes.

CONCLUSION

Patients with COPD are at an increased risk of developing RLS regardless of gender, age and occupation. The COPD patients with comorbidities should be particularly cautious about the RLS risk.

Effects of Chinese herbal medicines on dementia risk in patients with sleep disorders in Taiwan

ETHNOPHARMACOLOGICAL RELEVANCE

Sleep disorders affect an estimated 150 million people worldwide and result in adverse health, safety, and work performance-related outcomes that have important economic consequences. In Taiwan, Chinese herbal medicine (CHM) is a complementary natural medicine and has been widely used as an adjunctive therapy.

AIM OF THE STUDY

This study aimed to investigate the effect of CHM on dementia risk in patients with sleep disorders in Taiwan.

MATERIALS AND METHODS

We identified 124,605 patients with sleep disorders between the ages of 20 and 60 years. Of these, 5876 CHM users and 5876 non-CHM users were matched according to age and gender. The chi-squared test, Cox proportional hazard model, Kaplan-Meier method, and log-rank test were used for the comparisons. Association rule mining and network analysis were applied to determine a CHM pattern specialized for sleep disorders.

RESULTS

More CHM users did not use sleeping pills than non-CHM users. CHM users had a lower risk of dementia than non-CHM users after adjusting for age, gender, and sleeping pill use (hazard ratio (HR): 0.469, 95% CI = 0.289-0.760; p-value = 0.002). The cumulative incidence of dementia was lower among CHM users (long-rank test, p-value < 0.001). Association rule mining and network analysis showed that Ye-Jiao-Teng (YJT; Caulis Polygoni Multiflori; Polygonum multiflorum Thunb), Suan-Zao-Ren-Tang (SZRT), Jia-Wei-Xiao-Yao-San (JWXYS), He-Huan-Pi (HHP; Cortex Albizziae; Albizia julibrissin Durazz.), and Suan-Zao-Ren (SZR; Semen Zizyphi Spinosae; Ziziphus jujuba Mill.) were important CHMs for patients with sleep disorders in Taiwan.

CONCLUSIONS

A comprehensive list of herbal medicines may be useful for the clinical treatment of patients with sleep disorders, and for future scientific investigations into the prevention of dementia in these patients.

Budesonide/Formoterol Anti-Inflammatory Reliever and Maintenance or Fluticasone Propionate/Salmeterol Plus As-Needed, Short-Acting β2 Agonist: Real-World Effectiveness in pAtients without Optimally Controlled asThma (REACT) Study

Introduction

In the prospective, observational, 16-week REACT study conducted between October 21, 2008 and May 12, 2011, we compared the real-world effectiveness of anti-inflammatory reliever and maintenance therapy with budesonide/formoterol (Symbicort^® Turbuhaler) and maintenance therapy with fixed-dose fluticasone/salmeterol (Seretide^®) plus as-needed, short-acting β₂ agonists (SABAs) in Taiwanese patients with inadequate asthma control.

Methods

Asthma control was assessed using the five-item Asthma Control Questionnaire (ACQ-5) and standardized pulmonary function testing. Assessments were performed at baseline and at weeks 4–5 and 12–16. Overall, we enrolled 842 patients at 11 clinics, 723 of whom were included in analyses (budesonide/formoterol, 563.3±1.3 μg/d, n=551; fluticasone/salmeterol, 1013.8±1.4 μg/d, n=172).

Results

At baseline, 72.5% and 27.5% of all patients had “partly” and “uncontrolled” asthma, respectively. Mean±SD ACQ-5 scores were 1.54±1.06 and 1.46±1.28 in the budesonide/formoterol and fluticasone/salmeterol groups, respectively. ACQ-5 scores significantly improved from baseline (ie, decreased) in both groups at weeks 4 and 16. ACQ-5 difference scores were significantly lower in the budesonide/formoterol group (−0.91±1.11) than the fluticasone/salmeterol group (−0.69±1.27) at the end of the study (p=0.027). Peak expiratory flow rate significantly improved from baseline in the budesonide/formoterol but not the fluticasone/salmeterol group at the end of the study. Severe exacerbation rates and medical resource utilization were comparable between the budesonide/formoterol and fluticasone/salmeterol groups.

Conclusion

Collectively, results indicate the real-world effectiveness of budesonide/formoterol anti-inflammatory reliever and maintenance therapy is better than fixed-dose fluticasone/salmeterol plus as-needed SABA.

Trial Registration

ClinicalTrials.gov registration number: NCT00784953.

Clinical characteristics of Asian patients with sleep apnea with low arousal threshold and sleep structure change with continuous positive airway pressure

PURPOSE

Low respiratory arousal threshold (ArTH) has been observed to be prevalent in patients with obstructive sleep apnea (OSA), and is associated with poor adherence to continuous positive airway pressure (CPAP) treatment. This study aimed to examine the associations between low ArTH and clinical characteristics. The second aim was to examine sleep structure changes between diagnostic polysomnography (PSG) and CPAP titration studies.

METHODS

PSG data for 3718 adults who had an apnea-hypopnea index (AHI) ≥ 5 were reviewed retrospectively, as well as 206 CPAP titration studies among these participants. Participants were dichotomized into low- and high-ArTH groups according to their PSG parameters. The associations between low ArTH and clinical characteristics were examined by multivariate logistic regressions. The sleep structure changes between PSG and CPAP titration studies were examined by repeated measures ANOVA.

RESULTS

Fifty percent of patients with OSA had low ArTH. Compared with high-ArTH patients, low-ArTH patients were less obese and composed of a higher percentage of women. In logistic regression models, low ArTH was associated with bruxism and nocturia, but not with illnesses after adjusting for AHI and body mass index. Compared with diagnostic PSG studies, low-ArTH patients had significantly decreased stage changes and increased percentage of rapid eye movement sleep during CPAP titration studies.

CONCLUSION

Low ArTH was prevalent in this large sample of patients with OSA. Arousal threshold was not associated with an increased risk of physical illnesses but was with certain clinical complaints. Low-ArTH patients benefited from CPAP titration study for improved sleep structure.

A Comparison of Each Sleep Stage Autonomic Nervous System Activity in Different Sleep Apnea Severity Levels

Sleep apnea has increasingly become a public health issue. To further elucidate the physiological changes in different sleep apnea severity levels, we analyzed the autonomic nervous system (ANS) activity in each sleep stage by heart rate variability (HRV), moreover, we clarified how sleep apnea severity affects hypnogram and sleep quality. Subjects used in this study was obtained from PhysioNet, and the patient data were grouped into mild, moderate, and severe levels of sleep apnea according to apnea–hypopnea index (AHI). The electrocardiogram readings during the period of free apnea were extracted and evaluated by HRV and represented to the sleep stages as follows: Awake, rapid eye movement (REM), and nonrapid eye movement (NREM) in different sleep apnea levels, respectively. The results indicated that the severe group (AHI ≥ 30 events per hour) has higher sympathetic nervous system (SNS) activity and lower parasympathetic nervous system (PNS) activity in NREM. This elevates the ANS tone in NREM similar to Awake, making the ANS activity between NREM and Awake indistinguishable. Furthermore, we evaluated the effects both with (w/) and without (w/o) apnea events in REM and NREM separately. Apnea events that occurred in REM (w/) were not different compared to those in REM (w/o). On the other hand, apnea events occurring in NREM (w/) activated SNS and suppressed PNS activity. This altered the ANS tone, which suggested an early sleep stage transition to REM or Awake. This study indicates how sleep apnea severity correlates to the imbalance of ANS activity and it might disrupt the normal hypnogram. Consequently, from the ANS point of view that patients with severe apnea do not get appropriate rest from sleeping, these patients need some medical interventions or treatment to prevent the development of chronic diseases.

Air Pollutants Are Associated With Obstructive Sleep Apnea Severity in Non-Rapid Eye Movement Sleep

STUDY OBJECTIVES

The relationship between seasonal variation of obstructive sleep apnea and ambient temperature and pollutants has been inconsistent in previous studies. It is also unknown whether the seasonal variation in apnea-hypopnea index influences continuous positive airway pressure treatment dose. This study aims to examine the seasonality of obstructive sleep apnea and continuous positive airway pressure treatment, and the association between air pollutants and apnea-hypopnea index in adults with different sleep apnea severity during different sleep stages.

METHODS

Polysomnography of 5,413 patients referred to one sleep center during 2008-2015 were examined retrospectively. Ambient conditions and air pollutants levels were collected from the official air condition surveillance database. Cosinor analysis was used to examine seasonal variances. The general linear model was used to examine associations between air conditions and apnea-hypopnea index adjusted for seasonality. Models for apnea-hypopnea index in different sleep stages, sex groups, and obstructive sleep apnea severity groups were analyzed separately.

RESULTS

Seasonal variations for continuous positive airway pressure treatment were not significant. Particulate matter less than or equal to 10 μm, ozone, sulfur dioxide, and relative humidity were associated with apnea-hypopnea index only in patients with severe obstructive sleep apnea. The association was significant only in non-rapid eye movement sleep.

CONCLUSIONS

An adjustment for continuous positive airway treatment dose by season is not warranted. Protection for air pollutant-vulnerable groups should be provided. The exact mechanism of the associations between apnea-hypopnea index and air conditions only in non-rapid eye movement sleep must be clarified.

Late chronotype and high social jetlag are associated with burnout in evening-shift workers: Assessment using the Chinese-version MCTQshift

Chronotypes are associated with shift work tolerance and sleep in shift workers, and sleep mediates the impact of shift work on mental health. However, the role of chronotype in the association between shift work and mental health has not been clarified. In this study, we aimed to examine the association between chronotype and burnout in shift workers, using the validated Munich ChronoType Questionnaire for shift workers (MCTQ^shift). A total of 288 shift workers with irregular shift frequencies were recruited and completed the Chinese-version MCTQ^shift and the Morningness-Eveningness Questionnaire (MEQ). Chronotypes were assessed by the calculation of corrected mid-sleep time (MSF_SC) from mid-sleep time on free days (MSF) based on their exact shift schedules. Another 26 evening-shift nurses were monitored with actigraphy for at least two consecutive evening shifts and the following two free days. Burnout was evaluated using the Copenhagen Burnout Inventory. We found that MSF^E_SC, MSF^E and mid-sleep time on workdays (MSW^E) had normal distributions and correlated significantly with MEQ scores (r = - 0.47, -0.45 and -0.47, respectively; all p < 0.001). MSW was more closely correlated with actigraphy-derived mid-sleep time on the free day before workdays than that on workdays (r = 0.61 and 0.48, respectively, p < 0.05). Sleep duration was significantly longer on workdays among evening-shift workers who slept late on workdays than those who slept early (β = 0.59, p < 0.001). After demographic and work characteristics were adjusted for in linear regression models, late chronotype and high social jetlag were associated with burnout scores in evening-shift workers. In conclusion, the Chinese-version MCTQ^shift is a valid tool for chronotype assessment. Interventions to improve sleep in shift workers should be tailored to chronotype due to variations in sleep behavior. Late chronotype may be an inherent feature of mental health problems, because the association with burnout was significant in both day workers in previous studies and shift workers.

CHA2DS2-VASc scores predict major adverse cardiovascular events in patients with chronic obstructive pulmonary disease

INTRODUCTION

Patients with chronic obstructive pulmonary disease (COPD) frequently experience concurrent comorbidities; therefore, risk assessment for major adverse cardiovascular events (MACEs) is very important.

OBJECTIVES

We explored the association between COPD and risk of MACEs with three common clinical events: acute myocardial infarction (AMI), ischemic stroke (IS), and cardiovascular death (CVD).

METHODS

We evaluated the predictive value of the CHA2DS2-VASc score (congestive heart failure [C], hypertension [H], age [A], diabetes [D], stroke [S], and vascular disease [VASc]) for MACEs in COPD patients. In this observational study, we retrospectively reviewed the records of 29 258 patients with COPD between 2005 and 2009 in relation to MACE risk using the CHA2DS2-VASc score. We calculated the hazard ratios (HR) and 95% confidence intervals (CI) using a significance level of .05.

RESULTS

Patients with COPD had significantly (P < .001) increased risk of MACEs, and a high prevalence of CHA2DS2-VASc scores ≥ 6, predicting MACEs (16.1%), AMI (3.3%), IS (8.7%), and CVD (4.0%). A good discrimination was found for MACEs, IS events, and CVD events (AUC = 0.740, 0.739, and 0.778, respectively) but poorer discrimination for AMI events (AUC = 0.697).

CONCLUSION

Early lifestyle modifications and antithrombotic therapy may be essential for COPD patients at a high risk of MACEs, that is, those with CHA2DS2-VASc scores ≥ 6.

Risk of obstructive sleep apnoea in patients with rheumatoid arthritis: a nationwide population-based retrospective cohort study

OBJECTIVE

Sleep disorders are prevalent medical disorders in patients with rheumatoid arthritis (RA). However, whether patients with RA are at an increased risk of developing obstructive sleep apnoea (OSA) is unclear.

DESIGN

Using population-based retrospective cohort study to examine the risk of OSA in patients with RA.

SETTING

We used claims data of the National Health Insurance Research Database (NHIRD) of Taiwan.

PARTICIPANTS

We identified a RA cohort with 33 418 patients newly diagnosed in 2000-2010 and a randomly selected non-RA comparison cohort with 33 418 individuals frequency matched by sex, age and diagnosis year.

PRIMARY AND SECONDARY OUTCOME MEASURES

Incident OSA was estimated by the end of 2011. The HRs of OSA were calculated using the Cox proportional hazards regression analysis.

RESULTS

The overall incidence rate of OSA was 75% greater in the RA cohort than in the non-RA cohort (3.04 vs 1.73/10 000 person-years, p<0.001), with an adjusted HR (aHR) of 1.75 (95% CI 1.18 to 2.60). Stratified analyses by sex, age group and comorbidity revealed that the incidence rates of OSA associated with RA were higher in all subgroups.

CONCLUSIONS

This population-based retrospective cohort study suggested that patients with RA should be monitored for the risk of developing OSA.

The relationships of sleep apnea, hypertension, and resistant hypertension on chronic kidney disease

Hypertension, blood pressure variation, and resistant hypertension have close relations to sleep apnea, which lead to target organ damage, including the kidney. The complex relationships between sleep apnea and blood pressure cause their interactions with chronic kidney disease ambiguous. The aim of the study was to elucidate the separate and joint effects of sleep apnea, hypertension, and resistant hypertension on chronic kidney disease. A cross-sectional study was done to see the associations of sleep apnea, hypertension, and resistant hypertension with chronic kidney disease in 998 subjects underwent overnight polysomnography without device-therapy or surgery for their sleep-disordered breathing. Multivariate logistic regression was used to analyze the severity of SA, hypertension stage, resistant hypertension, and their joint effects on CKD. The multivariable relative odds (95% CI) of chronic kidney disease for the aged (age ≥65 years), severe sleep apnea, stage III hypertension, and resistant hypertension were 3.96 (2.57-6.09) (P < 0.001), 2.28 (1.13-4.58) (P < 0.05), 3.55 (1.70-7.42) (P < 0.001), and 9.42 (4.22-21.02) (P < 0.001), respectively. In subgroups analysis, the multivariable relative odds ratio of chronic kidney disease was highest in patients with both resistant hypertension and severe sleep apnea [13.42 (4.74-38.03)] (P < 0.001). Severe sleep apnea, stage III hypertension, and resistant hypertension are independent risk factors for chronic kidney disease. Patients with both severe sleep apnea and resistant hypertension have the highest risks.

Predictive factors warrant screening for obstructive sleep apnea in COPD: a Taiwan National Survey

BACKGROUND AND OBJECTIVES

COPD and obstructive sleep apnea (OSA) share similar pathological processes and cardiovascular sequelae. Coexisting OSA in COPD - "overlap syndrome" - has worse prognosis than either condition alone, and appropriate treatment improves survival. Our objectives were to ascertain the frequency at which COPD coexists with the risk of OSA in Taiwan and to compare the risk factors, COPD symptoms, and life quality metrics between COPD subgroups with versus without risk of OSA.

METHODS

We conducted a random cross-sectional national telephone survey of adults >40 years old in Taiwan. Participants fulfilling an epidemiological case definition of COPD completed a questionnaire to assess COPD symptoms and OSA risk, comorbidities, and performance of daily activities. Data from COPD cohorts with and without risk of OSA were analyzed and compared.

RESULTS

Of 6,600 interviews completed, 404 subjects fit the epidemiological case definition of COPD - an overall prevalence of 6.1% in this national sample. Data on OSA risk were available for 292 of this COPD cohort, of whom 29.5% were at risk of OSA. Compared to those without risk of OSA, those with risk of OSA were significantly more likely to have hypertension or cardiovascular disease and diabetes, had significantly higher body mass index and COPD Assessment Test scores, and reported impaired work performance and leisure activities.

CONCLUSION

Among adults in Taiwan who fulfill epidemiologic criteria for COPD, 29.5% have coexisting risk of OSA. Comorbid hypertension or cardiovascular disease and diabetes are common and significantly more prevalent among the COPD population at risk of OSA than those who are not. OSA screening is warranted in patients with COPD with those risk factors that are more prevalent in COPD with risk of OSA than without, to target early interventions to reduce adverse cardiovascular sequelae from overlap syndrome.

Sleep medicine in Taiwan

The sleep medicine is a young medical science in Taiwan. It began from less than 10 sleep beds 20 years ago in four hospitals all over Taiwan. By the organization of sleep team in Chang Gung Memorial Hospital and the initiation of Taiwan Society of Sleep Medicine, sleep medicine becomes a popular medicine in the past decades. The setting of Sleep Society in 2002 is the milestone to promote the sleep medicine, educate the public and professionals, and control of the quality of clinical practice. Epidemiologic study in Taiwan shows many Taiwanese suffer from sleep disorders and hence more sleep institutes are needed. Accreditation has become a mission of the Taiwan Society of Sleep Medicine. Technicians, sleep centers, sleep specialists and sleep phycologists are gradually certified by the society. 215 sleep technicians, 307 sleep physicians, 31 iCBT therapists and 21 sleep centers are certified by the society till 2015. The first sleep related medical courses are initiated in the Department of Respiratory Therapy in Chang Gung University from 2003. For the following years, eight medical courses are set in six Universities now. Given the fact that the Asian accounts for the largest proportion of population in the world, investigation on the OSA in Asian population is essential. In this article, we aimed to demonstrate the outcomes of OSA-related research in Asia. In particular, the progress driven by the studies in Taiwan will be discussed. Data were obtained online from the Science Citation Index Expanded database of the Thomson Reuters' Web of Science Core Collection. Keywords including "apnea" and "hyponea" were used to search by applying the filters of the title and the publication years between 1991 and 2014. In total, 2623 articles were hit, subject to the criteria for data search. Among the 2623 articles, sleep and breathing related articles (128, 4.95 %) were the most frequently reported. Japan is the country that published the highest amount of OSA-related articles. The Asian institutions that ranked the first two in the number of OSA-related articles were Technion-Israel Institute of Technology and Tel Aviv University in Israel. In Taiwan, Chang Gung Memorial Hospital and Chang Gung University ranked fourth and fifth. Both institutes reported 63 articles. In Asia, Japan leads in the quantity of publication and the Japanese research institutes performed evenly. China had rapid growth in the number of articles since 2011. Although sleep medicine developed smoothly in the past decades in Taiwan, there were problems that the sleep society and specialists had to encounter. Insurance limits the expansion of sleep labs and the reimbursement is very low for sleep medicine to survive. The affiliations of sleep specialist and the sleep education are also important issue that the sleep specialists in the society have to discuss.The previous achievements do not guarantee future success. We have to face these problems seriously and take action for the following years to maintain the development of sleep medicine in Taiwan.

COPD in Taiwan: a National Epidemiology Survey

Objectives

To determine the prevalence of COPD in Taiwan and to document the disease characteristics and associated risk factors.

Methods

We conducted a random cross-sectional national survey of adults older than 40 years in Taiwan. Respiratory health screening questions identified subjects with diagnosed COPD or whose reported symptoms also fulfilled an epidemiological case definition; these were eligible to complete the survey, which also included indices of symptom severity and disability and questions on comorbidities, medical treatments, smoking habits, and occupations potentially harmful to respiratory health. Subjects with diagnosed COPD were subdivided by smoking status. Subjects who fulfilled the case definition of COPD and smoked were designated as “possible COPD”. Participants who did not fit the case definition of COPD were asked only about their personal circumstances and smoking habits. Data from these groups were analyzed and compared.

Results

Of the 6,600 participants who completed the survey, 404 (6.1%) fulfilled the epidemiological case definition of COPD: 137 with diagnosed COPD and 267 possible COPD. The most common comorbidities of COPD were hypertension or cardiovascular diseases (36.1%). Subjects with definite COPD had significantly higher COPD Assessment Test scores than the possible COPD group (14.6±8.32 vs 12.6±6.49, P=0.01) and significantly more comorbid illnesses (P=0.01). The main risk factors contributing to health care utilization in each COPD cohort were higher COPD Assessment Test scores (odds ratio [OR] 1.15, 95% confidence interval [CI] 1.04–1.26), higher modified Medical Research Council Breathlessness Scale scores (OR 1.97, 95% CI 1.11–3.51), and having more than one comorbidity (OR 5.19, 95% CI 1.05–25.61).

Conclusion

With estimated prevalence of 6.1% in the general population, COPD in Taiwan has been underdiagnosed. Symptoms and comorbidities were independent risk factors for health care utilization in subjects with definite or possible COPD. There is an urgent need to raise awareness of the importance of early evaluation and prompt treatment for subjects with chronic airway symptoms.

A psychometric assessment of the St. George's respiratory questionnaire in patients with COPD using Rasch model analysis

BACKGROUND

The St. George's Respiratory Questionnaire (SGRQ) was a widely used tool to assess disease impact on patients with obstructive airways disease. Although traditional methods have generally supported construct validity and internal consistency reliability of SGRQ, such methods cannot facilitate the evaluation of whether items are equivalent to different individuals. The purpose of this study is to rigorously examine the psychometric properties of the SGRQ in patients with chronic obstructive pulmonary disease (COPD) using Rasch model analysis.

METHODS

A methodological research was conducted on SGRQ in a sample of 240 male patients with COPD recruited from the outpatient services in Central Taiwan. The psychometric properties of the SGRQ were examined using Rasch model analysis with a mixed rating scale and partial credit mode by Winsteps software. The level of matching between the item's difficulty and person's ability was analyzed by item-person targeting as well as ceiling and floor effects. Item-person maps were also examined for checking the location of the item's difficulty and person's measures along the same scale. Finally, the differential item functioning (DIF) was examined to measure group equivalence associated with age and disease's severity.

RESULTS

Each of the three domains (Symptom, Activity, Impact) of the SGRQ was found to be unidimensionality. The person separation index ranged from 1.21 (Symptom domain) to 2.50 (Activity domain). There was a good targeting for the SGRQ domains, except the Impact domain (1.36). The percentage of ceiling and floor effects were below 10%, except the ceiling effect in the Impact domain (26.25%). From item-person maps, gaps of location of item corresponded to patient's ability were identified. The results have also showed that many items in SGRQ revealed age or severity related DIF.

CONCLUSIONS

Except the Symptom domain of SGRQ, the others have a reliabile internal consistency and a good hierarchical structure. The results of Rasch model analysis can highlight aspects for scale improvement, such as gap, duplicate items or scale responses. There was some age or severity related DIF indicating somewhat unstable across different characteristics of group. IRB No.: DMR94-IRB-179.

Obstructive sleep apnea is associated with liver disease: a population-based cohort study

BACKGROUND

The association between obstructive sleep apnea (OSA) and the risk of liver disease is unclear. Moreover, population-based studies on the risk of liver disease among people with OSA have not yet been conducted. This study aimed to investigate the risk of subsequent development of liver disease among people with OSA.

METHODS

Using Taiwan National Health Insurance claims data, this study collected subjects from a cohort of 17,374 people with OSA who were diagnosed between 2000 and 2008. A control group of 69,496 people was selected from the same database and matched by age, gender, urbanization, income, and date of initial admission. All subjects were followed up until 2010. Liver disease incidence and risk were calculated.

RESULTS

The overall risk of liver disease among people with OSA was significantly higher than in the control group (aHR = 5.52, p <0.001). Non-alcoholic fatty liver disease, cirrhosis, and hepatitis C had significant aHRs of 5.29, 7.50, and 7.19 (all at p <0.001), respectively. In contrast, hepatitis B had the smallest aHR of 3.71.

CONCLUSIONS

The risk of liver disease was more than five times higher among people with OSA compared with the control group; this was particularly for cirrhosis and hepatitis C. Liver disease is thus a very important health issue among people with OSA.

Validation of overnight oximetry to diagnose patients with moderate to severe obstructive sleep apnea

Background

Polysomnography (PSG) is treated as the gold standard for diagnosing obstructive sleep apnea (OSA). However, it is labor-intensive, time-consuming, and expensive. This study evaluates validity of overnight pulse oximetry as a diagnostic tool for moderate to severe OSA patients.

Methods

A total of 699 patients with possible OSA were recruited for overnight oximetry and PSG examination at the Sleep Center of a University Hospital from Jan. 2004 to Dec. 2005. By excluding 23 patients with poor oximetry recording, poor EEG signals, or respiratory artifacts resulting in a total recording time less than 3 hours; 12 patients with total sleeping time (TST) less than 1 hour, possibly because of insomnia; and 48 patients whose ages less than 20 or more than 85 years old, data of 616 patients were used for further study. By further considering 76 patients with TST < 4 h, a group of 540 patients with TST ≥ 4 h was used to study the effect of insufficient sleeping time. Alice 4 PSG recorder (Respironics Inc., USA) was used to monitor patients with suspected OSA and to record their PSG data. After statistical analysis and feature selection, models built based on support vector machine (SVM) were then used to diagnose moderate and moderate to severe OSA patients with a threshold of AHI = 30 and AHI = 15, respectively.

Results

The SVM models designed based on the oxyhemoglobin desaturation index (ODI) derived from oximetry measurements provided an accuracy of 90.42-90.55%, a sensitivity of 89.36-89.87%, a specificity of 91.08-93.05%, and an area under ROC curve (AUC) of 0.953-0.957 for the diagnosis of severe OSA patients; as well as achieved an accuracy of 87.33-87.77%, a sensitivity of 87.71-88.53%, a specificity of 86.38-86.56%, and an AUC of 0.921-0.924 for the diagnosis of moderate to severe OSA patients. The predictive outcome of ODI to diagnose severe OSA patients is better than to diagnose moderate to severe OSA patients.

Conclusions

Overnight pulse oximetry provides satisfactory diagnostic performance in detecting severe OSA patients. Home-styled oximetry may be a tool for severe OSA diagnosis.

Polysomnographic predictors of persistent continuous positive airway pressure adherence in patients with moderate and severe obstructive sleep apnea

Extensive use of continuous positive airway pressure (CPAP) has positive clinical benefits for most patients with obstructive sleep apnea (OSA). However, patient adherence is a major limiting factor to the effectiveness of CPAP treatment. This study determined the potential and quantifiable factors affecting the willingness of patients with OSA to undertake CPAP treatment by comparing the polysomnographic parameters recorded during diagnosis and titration. Patients with moderate and severe OSA who attended diagnostic polysomnography (PSG) and CPAP titration at the sleep center of China Medical University Hospital (CMUH) were included in the study. A total of 312 patients were divided into persistent users and nonusers of CPAP according to their use of in-home CPAP following titration and a 7-day CPAP trial. Multivariate logistic regression analyses were used to define the potential polysomnographic predictors of persistent CPAP adherence, and odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Most patients were men older than 50 years who were overweight or obese. Among the patients, 146 (46.8%) became persistent CPAP users. A 10% improvement of oxygen desaturation index (ODI) and a 10% increment in deep sleep percentage increased the chance of persistent CPAP use 1.18-fold and 1.07-fold, respectively. In addition, the improved ODI and deep sleep during CPAP titration increased the chance of persistent CPAP user. The polysomnographic parameters obtained from diagnosis and during titration can facilitate the prediction of persistent CPAP use.

Development and preliminary validation of a questionnaire on regular exercise beliefs among patients with chronic obstructive pulmonary disease

AIMS AND OBJECTIVES

To develop a Regular Exercise Belief Questionnaire and test its psychometric properties for patients with chronic obstructive pulmonary disease.

BACKGROUND

Regular exercise has been shown to significantly improve physical capacity and the quality of life of patients with chronic obstructive pulmonary disease. However, their adherence to long-term exercise is low. To develop an effective strategy for promoting good exercise behaviours, it is important to have a validated instrument to evaluate factors related to engaging in exercise.

DESIGN AND METHODS

A cross-sectional design was used for the study. Construction of the Regular Exercise Belief Questionnaire was based on the Theory of Planned Behaviour Reliability and validity were assessed using a sample of 136 male patients with chronic obstructive pulmonary disease. The construct validity of the questionnaire was confirmed through exploratory factor analysis and known group technique.

RESULTS

Exploratory factor analysis resulted in an eight-factor solution that explained 70·4% of the total variance. The internal consistency of the Regular Exercise Belief Questionnaire was 0·83-0·93. The Regular Exercise Belief Questionnaire was preliminarily found to be reliable and exhibited satisfactory validity for patients with chronic obstructive pulmonary disease.

CONCLUSION

The Regular Exercise Belief Questionnaire is the first theory-based measure of exercise beliefs among patients with chronic obstructive pulmonary disease. The questionnaire provides an effective method to examine behaviour beliefs, normative beliefs and control beliefs about regular exercise.

CLINICAL RELEVANCE

The measure can be used to periodically evaluate the exercise beliefs in clinics and to examine the effectiveness of exercise programmes in patients with chronic obstructive pulmonary disease. The result of the evaluation could also apply to identify strategies related to promoting exercise behaviours.

The stimulation effect of auricular magnetic press pellets on older female adults with sleep disturbance undergoing polysomnographic evaluation

Study Objectives. To examine the stimulation effect of auricular magnetic press pellet therapy on older female adults with sleep disturbance as determined by polysomnography (PSG). Design. Randomized, single-blind, experimental-controlled, parallel-group. Setting. Community. Participants. Twenty-seven older female adults with sleep disturbance according to the Pittsburgh Sleep Quality Index (PSQI) >5 for at least 3 months were recruited. Participants were screened by both the Hospital Anxiety and Depression Scale (HADS) and the Mini-Mental State Examination (MMSE), as well as polysomnography prior to randomization. Interventions. All eligible participants were randomly allocated into the experimental or control group. Both groups were taped with magnetic press pellet on auricular points for 3 weeks. The experimental group was treated by applying pressure on the magnetic press pellets 3 times per day while no stimulation was applied on the control group. Measurements and Results. Both groups were measured by PSG and PSQI at the beginning of the study and 3 weeks after the study. Both groups showed improvements on PSQI scores compared to the baseline. One-way analysis of covariance adjusted for baseline scores showed that significant improvements of PSG-derived sleep parameters, such as sleep efficiency, were found in the experimental group. However, no significant differences between groups were observed in the proportion of sleep stages with the exception of Stage 2. Conclusions. Auricular therapy using magnetic pellets and stimulation by pressing was more effective in improving the sleep quality compared to auricular therapy without any stimulation.

Assessing efficacy of indacaterol in moderate and severe COPD patients: a 12-week study in an Asian population

INTRODUCTION

This post hoc analysis evaluated the efficacy of indacaterol, a novel inhaled once-daily long-acting β(2)-agonist, by disease severity (GOLD 2005) in patients with moderate-to-severe COPD from six Asian countries/areas (Hong Kong, India, Japan, Korea, Singapore, Taiwan).

METHODS

Data from a 12-week, double-blind, placebo-controlled, parallel-group study in patients randomized to indacaterol 150 μg, indacaterol 300 μg or placebo once daily were analyzed based on baseline disease severity (moderate or severe). Endpoints were: trough FEV(1) (average of 23 h 10 min and 23 h 45 min post-dose values), transition dyspnoea index (TDI) and St George's Respiratory Questionnaire (SGRQ) at Week 12. Safety data were collected.

RESULTS

Of 347 patients randomized, 59.7% had moderate, and 40.3% had severe COPD. Least squares means (LSMs) indacaterol-placebo differences in trough FEV(1) at Week 12 exceeded the pre-specified minimal clinically important difference (MCID) of 0.12L and were statistically superior (p < 0.001) for indacaterol (150 μg, 300 μg) versus placebo in the two subgroups [0.19L, 0.20L (moderate); 0.15L, 0.19L (severe) respectively]. LSM TDI scores for both indacaterol doses versus placebo in both subgroups were statistically superior (p < 0.05) and clinically meaningful (≥1 unit). Both indacaterol doses showed improvements in LSM SGRQ total scores at Week 12 which exceeded the MCID (4 units) versus placebo in both subgroups, with indacaterol 300 μg-placebo difference in the severe subgroup being statistically significant (p < 0.01). Overall incidence of adverse events was lower with indacaterol than with placebo across both subgroups.

CONCLUSIONS

Indacaterol demonstrated clinically relevant improvements versus placebo in lung function, dyspnea and health status in Asian COPD patients irrespective of disease severity.

CLINICAL TRIALS IDENTIFIER

NCT00794157.

Efficacy and safety of indacaterol 150 and 300 µg in chronic obstructive pulmonary disease patients from six Asian areas including Japan: a 12-week, placebo-controlled study

BACKGROUND AND OBJECTIVE

The efficacy and safety of indacaterol, a novel inhaled once daily ultra long-acting β(2) -agonist was evaluated in COPD patients in six Asian countries/areas. This study was primarily designed to obtain the regulatory approval of indacaterol in Japan.

METHODS

Moderate-to-severe COPD patients were randomized to indacaterol 150 µg, indacaterol 300 µg or placebo once daily. Efficacy variables: trough FEV(1) (average of 23 h 10 min and 23 h 45 min post-dose values), health status (St. George's Respiratory Questionnaire) and transition dyspnoea index at week 12. Safety/tolerability was evaluated.

RESULTS

A total of 347 patients were randomized (96.5% male, mean (SD) age 66.7 (8.38) years, post-bronchodilator FEV(1) % predicted: 53.7 (12.50)); 88.8% completed. The least squares means (LSM) trough FEV(1) at week 12 for indacaterol 150 µg, indacaterol 300 µg and placebo were 1.34 L, 1.37 L and 1.17 L, respectively, with differences versus placebo exceeding the prespecified minimal clinically important difference of 0.12 L (0.17 L and 0.20 L for indacaterol 150 µg and 300 µg, respectively, both P < 0.001). The week 12 LSM transition dyspnoea index score was statistically superior for both indacaterol doses versus placebo (differences of 1.30 and 1.26, P < 0.001; both exceeding the minimal clinically important difference of 1). At week 12, both indacaterol doses provided statistically significant (P ≤ 0.005) and clinically meaningful (≥4 units) improvements in LSM St. George's Respiratory Questionnaire total score versus placebo (differences: -4.8 and -5.7 units). Adverse events for indacaterol (49.1%, both doses) were lower than placebo (59.0%) and were mostly mild/moderate in severity; no deaths were reported.

CONCLUSIONS

Indacaterol provided clinically significant bronchodilation and improvements in dyspnoea and health status in Asian COPD patients.

Association of DNA double-strand break gene XRCC6 genotypes and lung cancer in Taiwan

AIM

The DNA repair gene X-ray repair complementing defective repair in Chinese hamster cells 6 (XRCC6) is thought to play an important role in the repair of DNA double-strand breaks. It is known that defects in double-strand break repair capacity can lead to irreversible genomic instability. However, the association of polymorphic variants of XRCC6 with lung cancer susceptibility has never been reported. In this hospital-based case-control study, the association of XRCC6 promoter T-991C (rs5751129), promoter G-57C (rs2267437), promoter G-31A (rs132770), and intron 3 (rs132774) polymorphisms with lung cancer risk in a Taiwanese population, was studied.

MATERIALS AND METHODS

In total, 358 patients with lung cancer and 716 healthy controls recruited from the China Medical Hospital in Taiwan were genotyped.

RESULTS

The results showed that there were significant differences between lung cancer and control groups in the distribution of their genotypic (p=3.7×10(-4)) and allelic frequency (p=2.7×10(-5)) in the XRCC6 promoter T-991C polymorphism. Individuals who carried at least one C allele (TC or CC) had a 2.03-fold increased odds ratio of developing lung cancer compared to those who carried the wild-type TT genotype (95% conference internal=1.42-2.91, p=0.0001). For the other three polymorphisms, there was no difference between the case and control groups in the distribution of either genotypic or allelic frequency.

CONCLUSION

In conclusion, the XRCC6 promoter T-991C, but not the promoter C-57G, promoter G-31A or intron 3, is associated with lung cancer susceptibility.

Interaction of CCND1 genotype and smoking habit in Taiwan lung cancer patients

AIM

Cyclin D1 (CCND1) is critical in the transition of the cell cycle from G1 to S phase and unbalanced cell cycle regulation is a hallmark of carcinogenesis. The study aimed at investigating the association of CCND1 genotypes with lung cancer risk in Taiwan and examining the interaction between CCND1 genotype and smoking habit.

PATIENTS AND METHODS

CCND1 A870G (rs9344) and C1722G (rs678653) genotypes were determined by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis of DNA from the blood of 358 lung cancer patients and 716 cancer-free healthy controls.

RESULTS

The results showed that there were significant differences between lung cancer and control groups in the distribution of the genotypes (p=0.0003) and allelic frequency (p=0.0007) in the CCND1 rs9344 genotype. Individuals who carried AG or GG genotype had 0.59- and 0.52-fold risk, respectively, of developing lung cancer compared to those who carried the AA genotype (95% CI=0.44-0.78 and 0.35-0.79, respectively). There was also an obvious interaction of CCND1 rs9344 genotype with personal smoking habit on lung cancer risk (p=0.0009).

CONCLUSION

These findings support the conclusion that cell cycle regulation may play a role in lung cancer development and that CCND1 rs9344 polymorphism together with smoking habit maybe a useful biomarker for lung cancer prediction.

Outcome predictors of cirrhotic patients with spontaneous bacterial empyema

BACKGROUND

Spontaneous bacterial empyema (SBE) is a complication of cirrhotic patients in which a pre-existing pleural effusion becomes infected. This retrospective study was designed to investigate the bacteriology and outcome predictors of SBE in cirrhotic patients.

METHODS

Medical records of cirrhotic patients treated in a tertiary care university hospital from December 2004 to December 2008 were retrospectively reviewed.

RESULTS

Of 3390 cirrhotic patients seen during the study period, 81 cases of SBE were diagnosed. The incidence of SBE was 2.4% (81/3390) in cirrhotic patients and 16% (81/508) in patients with cirrhosis with hydrothorax. There were 46 monomicrobial infections found in 46 SBE patients. Aerobic Gram-negative organisms were the predominant pathogens (n=29, 63%), and Escherichia coli (n=9, 20%) was the most frequently isolated sole pathogen. The mortality rate of SBE was 38% (31/81). Univariate analysis showed that Child-Pugh score, model for end-stage liver disease (MELD)-Na score, concomitant bacteraemia, concomitant spontaneous bacterial peritonitis, initial intensive care unit (ICU) admission and initial antibiotic treatment failure were predictors of poor outcomes. Multivariate regression analysis demonstrated that the independent factors related to a poor outcome were initial ICU admission [odds ratio (OR): 4.318; 95% confidence interval 1CI) 1.09-17.03; P=0.037], MELD-Na score (OR: 1.267; 95% CI 1.08-1.49; P=0.004) and initial antibiotic treatment failure (OR: 13.10; 95% CI 2.60-66.03).

CONCLUSION

Spontaneous bacterial empyema in cirrhotic patients is a high mortality complication. The independent factors related to poor outcome are high MELD-Na score, initial ICU admission and initial antibiotic treatment failure. High MELD-Na score may be a useful mortality predictor of SBE in cirrhotic patients.

Clinical characteristics and outcomes of patients with obstructive sleep apnoea requiring intensive care

We reviewed the clinical characteristics, required intervention and short- and long-term outcomes in obstructive sleep apnoea (OSA) patients requiring intensive care. A retrospective, single-centre, observational cohort study was undertaken in a multidisciplinary teaching medical and surgical intensive care unit. Adult patients with OSA (apnoea-hypopnoea index of 5 or higher) requiring intensive care from January 2000 to January 2005 were included. Thirty-seven OSA patients (age: 58 +/- 14 years, male:female 27:10) were admitted due to respiratory (n=12, 32%), cerebrovascular (n=8, 22%), cardiovascular (n=16, 43%) and infectious events (n=1, 2.7%). Comparing the clinical features, polysomnographic data and outcome among these groups, we found that OSA patients admitted due to respiratory events had significantly higher Acute Physiology and Chronic Health Evaluation II scores, lower arterial blood gas pH, higher PaCO2, a higher incidence of respiratory failure (92%) and required non-invasive ventilation after extubation (73%), and higher intensive care unit readmission rates than patients admitted due to cerebrovascular events and cardiovascular events (P < 0.05). No difference was found in the in-hospital and long-term mortality rate. The most common reason for intensive care unit admission in critically ill OSA patients was a cardiovascular event, followed by respiratory and cerebrovascular events. The baseline polysomnographic data of the OSA patients were not correlated with their clinical features and outcomes in the intensive care unit. A more complicated clinical course and higher intensive care unit readmission rate were encountered in OSA patients admitted due to respiratory events. Further studies would be required to evaluate the efficacy of non-invasive ventilation for facilitation of extubation in OSA patients presenting with hypercapnic respiratory failure.

Curcumin induces apoptosis in human non-small cell lung cancer NCI-H460 cells through ER stress and caspase cascade- and mitochondria-dependent pathways

It has been reported that curcumin inhibited various types of cancer cells in vitro and in vivo. However, mechanisms of curcumin-inhibited cell growth and -induced apoptosis in human non-small cell lung cancer cells (NCI-H460) still remain unclear. In this study, NCI-H460 cells were treated with curcumin to determine its anticancer activity. Different concentrations of curcumin were used for different durations in NCI-H460 cells and the subsequent changes in the cell morphology, viability, cell cycle, mRNA and protein expressions were determined. Curcumin induced apoptotic morphologic changes in NCI-H460 cells in a dose-dependent manner. After curcumin treatment, BAX and BAD were up-regulated, BCL-2, BCL-X(L) and XIAP were down-regulated. In addition, reactive oxygen species (ROS), intracellular Ca(2+) and endoplasmic reticulum (ER) stress were increased in NCI-H460 cells after exposure to curcumin. These signals led to a loss of mitochondrial membrane potential (Delta Psi(m)) and culminated in caspase-3 activation. Curcumin-induced apoptosis was also stimulated through the FAS/caspase-8 (extrinsic) pathway and ER stress proteins, growth arrest- and DNA damage-inducible gene 153 (GADD153) and glucose-regulated protein 78 (GRP78) were activated in the NCI-H460 cells. Apoptotic cell death induced by curcumin was significantly reversed by pretreatment with ROS scavenger or caspase-8 inhibitor. Furthermore, the NCI-H460 cells tended to be arrested at the G(2)/M cell cycle stage after curcumin treatment and down-regulation of cyclin-dependent kinase 1 (CDK1) may be involved. In summary, curcumin exerts its anticancer effects on lung cancer NCI-H460 cells through apoptosis or cell cycle arrest.

Interaction of cyclooxygenase 2 genotype and smoking habit in Taiwanese lung cancer patients

AIM

The aim of this study was to evaluate the association and interaction of genotypic polymorphisms in the cyclooxygenase 2 (Cox-2) gene with smoking habits with lung cancer patients in Taiwan. Six polymorphic variants of Cox-2 were analysed in association with their effect on lung cancer susceptibility, and their joint effects with smoking habits on lung cancer risk is discussed.

MATERIALS AND METHODS

Three hundred and fifty-eight patients with lung cancer and 716 healthy controls from the China Medical Hospital in central Taiwan were genotyped.

RESULTS

The Cox-2 intron 6 (rs2066826) genotypes were distributed differently between the lung cancer and control groups. The A allele of Cox-2 intrin 6 was found more frequently in the cancer patient group than in the controls. Furthermore, the interactions of smoking with genetic factors were significant for the Cox-2 intron 6 genotypes. Patients who smoked and had the Cox-2 intron 6 AG or AA genotype had an increased risk of 2.21 (95% confidence interval=1.53-3.27) for developing lung cancer.

CONCLUSION

These results provide evidence that the A allele of Cox-2 intron 6 may be associated with the development of lung cancer and may be a useful marker for early detection and treatment of lung cancer.

Interaction of methylenetetrahydrofolate reductase genotype and smoking habit in Taiwanese lung cancer patients

The aim of this study was to evaluate the association and interaction of genotypic polymorphisms in methylenetetrahydrofolate reductase (MTHFR) and environmental factors with lung cancer in Taiwan. Two well-known polymorphic variants of MTHFR, C677T (rs1801133) and A1298C (rs1801131), were analyzed in association with lung cancer susceptibility, and discussed their joint effects with individual habits on lung cancer risk.

PATIENTS AND METHODS

In total, 358 patients with lung cancer and 716 healthy controls recruited from the China Medical Hospital in central Taiwan were genotyped.

RESULTS

The MTHFR C677T genotype, but not the A1298C, was differently distributed between the lung cancer and control groups. The T allele of MTHFR C677T was significantly more frequently found in controls than in cancer patients. As for A1298C polymorphism, there was no difference in distribution between the lung cancer and control groups. Gene interactions with smoking were significant for MTHFR C677T polymorphism. The MTHFR C677T CT and TT genotypes in association with smoking conferred a decreased risk of 0.706 (95% confidence interval=0.531-0.939) for lung cancer.

CONCLUSION

Our results provide the first evidence that the C allele of MTHFR C677T may be associated with the development of lung cancer and may be a novel useful marker for primary prevention and anticancer intervention.

Comparison of the indices of oxyhemoglobin saturation by pulse oximetry in obstructive sleep apnea hypopnea syndrome

OBJECTIVES

To comprehensively evaluate the ability and reliability of the representative previously proposed oxyhemoglobin indexes derived automatically for predicting the severity of obstructive sleep apnea hypopnea syndrome (OSAHS).

METHODS

Patients with a diagnosis of OSAHS by standard polysomnography were recruited from China Medical University Hospital Centre. There were 257 patients in the learning set and 279 patients in the validation set. The presence of OSAHS was defined as apnea-hypopnea index (AHI) > 5/h. Three kinds of oxyhemoglobin indexes, including the oxyhemoglobin desaturation index (ODI), time-domain index, and frequency-domain index, were used. Degrees of severity were AHI > 15/h and AHI > 30/h, representing moderate and severe OSAHS. A total of 28 oxyhemoglobin indexes were tested in our study.

RESULTS

Among the three kinds of indexes, ODI had a better diagnostic performance than the time-domain and frequency-domain indexes, with the results coincident in the validation set and learning set. For predicting the severity of OSAHS with AHI > 15/h or > 30/h, the ODI clinically had the higher correlation with AHI than time-domain and frequency-domain indexes, with sensitivity/specificity achieving 84.0%/84.3% in AHI > 15/h and 87.8%/96.6% in AHI > 30/h, respectively.

CONCLUSIONS

Based on the smaller SEE of the AHI, the ODI had a significantly smaller SEE than the time-domain and frequency-domain indexes. The ODI index provided a high level of diagnostic sensitivity and specificity at different degrees of OSAHS severity.

An empirical comparison of the WHOQOL-BREF and the SGRQ among patients with COPD

Aims

To compare the psychometric properties of the World Health Organization Quality of Life-BREF (WHOQOL-BREF) instrument and the St. George’s Respiratory Questionnaire (SGRQ), and to examine the association between pulmonary function and domains and items of these questionnaires in patients with chronic obstructive pulmonary disease (COPD).

Methods

The WHOQOL-BREF and the SGRQ were administered to 211 patients. The reliability and validity of, and correlations among, the domain scores were examined. Multiple regression analyses were performed to identify which items were independently associated with subjects’ lung functions.

Results

Both questionnaires showed good internal consistency (α > 0.8), except the SGRQ symptoms domain (α = 0.66), minimal ceiling and floor effects, and good item convergent and item discriminant validity. There were moderate correlations between physical domain of the WHOQOL-BREF and activity, impacts and total domains of the SGRQ, and between psychological domain of the WHOQOL-BREF and impacts and total domains of the SGRQ. Eighteen items were significantly associated with lung function, particularly those items relating to mobility/walking and activities of daily living (ADL).

Conclusion

Both the WHOQOL-BREF and the SGRQ showed comparable reliability and validity. Items related to mobility/walking and ADL may be useful in clinical screening for lung function impairment.

Urinary biomarker of oxidative stress correlating with outcome in critically septic patients

OBJECTIVE

To determine whether urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG), an in vivo parameter of oxidative stress, is correlated with the outcome of critically septic patients.

DESIGN AND SETTING

Clinical outcome study in an adult medical ICU.

PATIENTS

Eighty-five consecutive septic patients: 59 men and 26 women.

MEASUREMENTS AND RESULTS

Urinary 8-OHdG was analyzed using isotope-dilution liquid chromatography with tandem mass spectrometry (LC/MS/MS). ICU mortality in these 85 septic patients was 25.9% (n = 22) and hospital mortality 38.8% (n = 33). APACHE II scores of survivors on day 1, on day 3, and the difference between them differed significantly from those of nonsurvivors (day 1, 21.0 +/- 7.1 vs. 25.9 +/-8.0; day 3, 15.0 +/- 5.8 vs. 23.2 +/- 8.3; difference, 6.0 +/- 5.5 vs. 1.7 +/- 6.6). Urinary 8-OHdG was significantly lower in survivors than in nonsurvivors on day 1 (1.8 +/- 2.4 vs. 3.0 +/- 2.4). The area under receiver operating characteristic curve analysis for the association between day 1 urinary 8-OHdG and ICU mortality was 0.71. The comparison performed upon discharge from hospital revealed similar results.

CONCLUSIONS

This is a preliminary study. The excretion of the urinary 8-OHdG, as measured using isotope-dilution LC/MS/MS, as the APACHE II score, were correlated with the outcome of critically septic patients in medical ICU.

Urinary biomarker of oxidative stress correlating with outcome in critically septic patients

OBJECTIVE

To determine whether urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG), an in vivo parameter of oxidative stress, is correlated with the outcome of critically septic patients.

DESIGN AND SETTING

Clinical outcome study in an adult medical intensive care unit (ICU).

PATIENTS

85 consecutive septic patients (59 men, 26 women).

MEASUREMENTS AND RESULTS

Patient characteristics and the clinical course were examined. Urinary 8-OHdG was analyzed using isotope-dilution liquid chromatography with tandem mass spectrometry (LC/MS/MS). ICU mortality was 25.9% (22/85) and hospital mortality 38.8% (33/85). Survivors' APACHEII scores on days 1 and 3 and the difference between them differed significantly from those of nonsurvivors (day 1, 21.0+/-7.1 vs. 25.9+/-8.0; day 3, 15.0+/-5.8 vs. 23.2+/-8.3; difference, 6.0+/-5.5 vs. 1.7+/-6.6). Urinary 8-OHdG was significantly lower in survivors than in nonsurvivors on day 1 (1.8+/-2.4 vs. 3.0+/-2.4). The area under receiver operating characteristic curve analysis for the association between day 1 urinary 8-OHdG and ICU mortality was 0.71. The comparison performed upon discharge from hospital revealed similar results.

CONCLUSIONS

This is a preliminary study. Excretion of urinary 8-OHdG, as measured using isotope-dilution LC/MS/MS, and the APACHE II score were correlated with the outcome of critically septic patients in medical ICU.

Sonographic septation in lymphocyte-rich exudative pleural effusions: a useful diagnostic predictor for tuberculosis

OBJECTIVE

The purpose of this study was to evaluate the role of the sonographic features of lymphocyte-rich exudative pleural effusions in the differential diagnosis of tuberculosis and lung cancer in an area with a high incidence of tuberculosis.

METHODS

Medical records of patients undergoing chest sonography between January 2003 and June 2005 (30 months) were reviewed retrospectively. The enrolled patients included 73 with lung cancer-related pleural effusions and 93 with tuberculous pleural effusions. The sonographic appearances of the pleural effusions were defined in terms of 4 patterns: anechoic, homogeneously echogenic, complex septated, and complex nonseptated.

RESULTS

Among the 73 lung cancer-related pleural effusions, there were sonographic appearances of an anechoic pattern in 11% (8/73), a complex septated pattern in 4% (3/73), and a complex nonseptated pattern in 85% (62/73). In 93 tuberculous pleural effusions, there were sonographic appearances of an anechoic pattern in 12% (11/93), a complex septated pattern in 47% (44/93), and a complex non-septated pattern in 41% (38/93). Apparently, a complex septated pattern in the sonographic appearance of lymphocyte-rich pleural effusions is a useful diagnostic predictor for differentiating tuberculosis from lung cancer (95% confidence interval, -0.57 to -0.29). If we define the complex septated pattern in the sonographic appearance of lymphocyte-rich exudative pleural effusions as a predictor for tuberculous pleural effusions, we can achieve sensitivity, specificity, positive predictive value, negative predictive value, and positive likelihood ratio values of 47%, 96%, 94%, 59%, and 12, respectively.

CONCLUSIONS

A complex septated pattern in the sonographic appearance is a useful predictor of tuberculosis in lymphocyte-rich exudative pleural effusions.

The changing pathogens of complicated parapneumonic effusions or empyemas in a medical intensive care unit

OBJECTIVES

To assess the incidence, pathogens, and outcome of complicated parapneumonic effusions or empyemas in a medical intensive care unit (MICU) patients with pleural effusions.

DESIGN AND SETTING

Prospective study of febrile MICU patients with pleural effusion carried out in a tertiary care hospital between April 2001 and September 2003.

PATIENTS

The study included 175 patients with a temperature above 38 degrees for more than 8 h with evidence of pleural effusion confirmed by chest radiography and ultrasound.

INTERVENTION

Routine thoracentesis and effusion cultures.

RESULTS

The prevalence of complicated parapneumonic effusions or thoracic empyemas in febrile MICU patients with pleural effusions was 45% (78/175). A total of 78 micro-organisms were isolated from the pleural fluid of 58 patients (positive microbiological culture 74%) including aerobic Gram-negative (n=45), aerobic Gram-positive (n=23), anaerobic (n=5), Myobacterium tuberculosis (n=3), and Candida (n=2). The infection-related mortality rate of complicated parapneumonic effusions or empyemic patients in the MICU was 41% (32/78).

CONCLUSION

The development of complicated parapneumonic effusions or thoracic empyemas in MICU patients is a high-mortality disease. The increasing incidence of aerobic Gram-negative pathogens in empyema has become a more urgent problem.

A pilot trial of quantitative Tc-99m HMPAO and Ga-67 citrate lung scans to detect pulmonary vascular endothelial damage and lung inflammation in patients of collagen vascular diseases with active diffuse infiltrative lung disease

Diffuse infiltrative lung disease (ILD) includes a heterogeneous group of disorders predominantly affecting lung parenchyma and sparing the airway. To assess the degree of pulmonary vascular endothelial damage in active ILD, lung/liver uptake ratios (L/L ratio) on technetium-99m hexamethylpropylene amine oxime (Tc-99m HMPAO) lung scan were determined in 30 patients with active ILD. Meanwhile, the gallium-67 citrate (Ga-67) uptake index (GUI) on Ga-67 lung scan was used to evaluate the severity of lung inflammation in active ILD. In this study, high-resolution CT (HRCT) was used to evaluate disease activity in ILD. The results show statistically significant differences between normal controls and patients with active ILD as shown in L/L ratios and GUI. However, when the patients were divided into two groups of 15 patients with normal chest X-ray findings and 15 with abnormal X-ray findings, there was no significant difference in those parameters. In addition, there was no statistically significant difference between the groups in HRCT scoring. No good correlation between the degree of pulmonary vascular endothelial damage and the severity of lung inflammation was found. In addition, there were no good correlations between HRCT scoring vs GUI and HRCT vs L/L ratio in different study subgroups. In conclusion, L/L ratios on Tc-99m HMPAO and GUI on Ga-67 lung scans differ from chest X-ray findings and have the potential to detect the degree of pulmonary vascular endothelial damage and severity of lung inflammation in active IDL. However, the relationships between HRCT scoring, GUI, and L/L ratio in patients with collagen vascular diseases and active ILD are not significant.