Ocular surface disturbance in patients after acute COVID-19.

BACKGROUND: We investigated the ocular surface disturbances in COVID-19 patients discharged from the hospital. METHODS: One hundred and seventy-nine eyes of 109 healthy participants and 456 eyes of 228 post-COVID-19 patients received comprehensive eye examinations; the latter were interviewed with questionnaires on ocular symptoms before and after COVID-19 diagnosis. Associations of ocular surface manifestations with virological and ophthalmic parameters were evaluated by multivariable mixed linear or logistic regression models. RESULTS: Mean interval between COVID-19 diagnosis and ophthalmic evaluation was 52.23 ± 16.12 days. The severity of meibomian gland dysfunction (MGD) based on clinical staging was higher in post-COVID-19 than healthy eyes (1.14 ± 0.67 vs. 0.92 ± 0.68, p = 0.002) and so was ocular surface staining score (0.60 ± 0.69 vs. 0.49 ± 0.68, p = 0.044). Patients requiring supplementary oxygen during hospitalisation had shorter tear break-up time (ß -1.63, 95% CI -2.61 to -0.65). Cycle threshold (Ct) value from upper respiratory samples (inversely correlated with viral load) at diagnosis had an OR = 0.91 (95% CI 0.84-0.98) with new ocular surface symptoms 4 weeks after diagnosis. The presence of ocular surface symptoms 1 week prior to COVID-19 diagnosis showed an OR of 20.89 (95% CI 6.35-68.66) of persistent or new ocular symptoms 4 weeks afterward. CONCLUSIONS: MGD and ocular surface staining are more common and severe in post-COVID-19 patients. Patients with higher viral loads have greater risks of ocular surface symptoms. Patients requiring supplementary oxygen are more likely to show tear film instability. Ocular surface evaluation should be considered 1-3 months following hospital discharge for any COVID-19 patient.

Effect of Weight Loss and Continuous Positive Airway Pressure on Obstructive Sleep Apnea and Metabolic Profile Stratified by Craniofacial Phenotype: A Randomized Clinical Trial.

Rationale: Craniofacial structure is believed to modulate the effect of weight loss on obstructive sleep apnea (OSA), but whether this affects metabolic profile after weight loss compared with continuous positive airway pressure (CPAP) is unknown among obese Chinese patients with OSA. Objectives: To compare the change in metabolic profile between a lifestyle modification program (LMP), stratified by craniofacial phenotype, and CPAP therapy for 6 months. Methods: We randomly assigned 194 patients with body mass index ⩾ 25 kg/m2 and moderate to severe OSA to participate in the LMP or receive CPAP therapy for 6 months in a 2:1 ratio. Assessments included computed tomography for assessing maxillomandibular volume (MMV), hsCRP (high-sensitivity C-reactive protein), and insulin sensitivity. Measurements and Main Results: Among 128 and 66 subjects in the LMP and CPAP groups, respectively, hsCRP was reduced more in the LMP group than the CPAP group (median [interquartile range], -0.7 [-1.4 to -0.0] vs. -0.3 [-0.9 to 0.4] mg/L; P = 0.012). More patients in the LMP group achieved low hsCRP (<1 mg/L) than the CPAP group (21.1% vs. 9.1%; P = 0.04). Insulin sensitivity improved only in the LMP group, with 3.1 (95% confidence interval, 1.5-6.6) times more patients with normal glucose regulation after intervention. The LMP group was stratified into LMP-small MMV (n = 64) and LMP-large MMV (n = 64) groups according to the median MMV value of 233.2 cm3. There was no significant difference in hsCRP (median [interquartile range], -0.7 [-1.3 to 0.1] vs. -0.7 [-1.5 to -0.2] mg/L; P = 0.884) and insulin sensitivity (median [interquartile range], 0.5 [-0.2 to 1.9] vs. 0.6 [0.1 to 2.0]; P = 0.4860) between the LMP-small MMV and LMP-large MMV groups. Conclusions: Weight reduction alleviated subclinical inflammation and improved insulin sensitivity more than CPAP among obese Chinese patients with moderate to severe OSA, and this effect was not influenced by craniofacial structure. Clinical trial registered with www.clinicaltrials.gov (NCT03287973).

Collection of lower respiratory specimen by bronchoscopy for the diagnosis of COVID-19.

Bronchoscopy, as an aerosol-generating procedure, is not routinely performed in patients with high-risk of coronavirus disease-2019 (COVID-19) owing to potential transmission to healthcare workers. However, to obtain lower respiratory specimens from bronchoscopy with bronchoalveolar lavage (BAL) is necessary to confirm COVID-19 or other diagnosis that will change clinical management. We report a case of diagnostic difficulty with five negative SARS-CoV-2 RT-PCR testing in four upper respiratory tract and one stool samples following presentation with fever during the quarantine period and a strong epidemiological linkage to an index patient with COVID-19. The final diagnosis was confirmed by BAL. Special precautions to be taken when performing bronchoscopy in high-risk non-intubated patients were discussed.

Impact of diabetes on COVID-19 and other infection: Report from the 22nd Hong Kong Diabetes and Cardiovascular Risk Factors-East Meets West Symposium.

The coronavirus disease 2019 (COVID-19) pandemic has posed enormous challenges to healthcare systems worldwide. The negative impact of COVID-19 is widespread and includes not only people who contracted the disease but also those with chronic morbidities such as diabetes whose care is compromised due to diversion of medical resources. People with diabetes are generally more susceptible to infection as a result of altered immunity. People with diabetes have a worse prognosis from COVID-19 and there is evidence to suggest that severe acute respiratory syndrome coronavirus 2 may directly affect pancreatic function precipitating hyperglycaemic crises. In the United Kingdom, one of the most heavily affected countries, guidelines are in place to unify the management of people with diabetes hospitalized for COVID-19. Diabetes services are re-organized to ensure that medical care of people with diabetes is maintained despite resource and other practical constraints. Public health measures including social distancing, hand hygiene and the use of face masks are crucial in containing community transmission of the virus. Hong Kong, one of the most densely populated city in the world, is particularly vulnerable and has in place a stringent containment policy and aggressive contact tracing to ensure public safety during this pandemic.

Continuous Positive Airway Pressure Does Not Improve Nonalcoholic Fatty Liver Disease in Patients with Obstructive Sleep Apnea. A Randomized Clinical Trial.

Rationale: Obstructive sleep apnea (OSA) is associated with development of nonalcoholic fatty liver disease (NAFLD). The effects of continuous positive airway pressure (CPAP) on NAFLD in patients with concomitant OSA are unknown.Objectives: To investigate the effects of autoadjusting CPAP versus subtherapeutic CPAP treatment over 6 months on NAFLD activities.Methods: Patients with NAFLD and OSA, as defined by respiratory event index ≥5/h diagnosed by a validated level 3 Embletta device, were randomized into group A) autoadjusting CPAP (4-20 cm H2O) or group B) subtherapeutic CPAP (pressure fixed at 4 cm H2O). The primary endpoint was the difference in changes in intrahepatic triglyceride as measured by proton magnetic resonance spectroscopy after 6 months of therapy. Key secondary endpoints included changes in controlled attenuation parameter (CAP) and liver stiffness measurement measured with transient elastography, and serum cytokeratin-18 fragment.Measurements and Main Results: A total of 120 patients were randomized equally into two groups. There were significant correlations between CAP and respiratory event index (r = 0.203, P = 0.026), percentage of total recording time with SaO2 < 90% (r = 0.265, P = 0.003), and oxygen desaturation index (r = 0.214, P = 0.019). After 6 months of treatment, there were no significant differences of changes in primary and secondary endpoints between the two treatment groups. Regression analysis showed that weight change over 6 months correlated with changes in both intrahepatic triglyceride and CAP (P < 0.001).Conclusions: Despite significant correlations between hepatic steatosis and markers of severity of OSA, CPAP alone did not improve hepatic steatosis and fibrosis. However, the additional role of weight reduction through lifestyle modification deserves further investigation.

Continuous positive airway pressure for obstructive sleep apnoea does not improve asthma control.

BACKGROUND AND OBJECTIVE: Unrecognized obstructive sleep apnoea syndrome (OSAS) may lead to poor asthma control despite optimal therapy. We assessed asthma control, airway responsiveness, daytime sleepiness and health status at baseline and 3 months after continuous positive airway pressure (CPAP) treatment among asthma patients with nocturnal symptoms and OSAS. METHODS: Patients with nocturnal asthma symptoms despite receiving at least moderate-dose inhaled corticosteroid and long-acting bronchodilators underwent a home sleep study using 'Embletta' portable diagnostic system. Patients with significant OSAS (apnoea-hypopnoea index (AHI) ≥10/h) were randomized to receive either CPAP or conservative treatment for 3 months. RESULTS: Among 145 patients recruited, 122 underwent sleep study with 41 (33.6%) having AHI ≥10/h. Patients with significant OSAS had higher BMI (27.4 (5.1) vs 25.1 (4.5) kg/m2 , P = 0.016), bigger neck circumference (36.6 (3.1) vs 34.8 (3.6) cm, P = 0.006) and lower minimum SaO2 (80.7 (6.6) vs 87.2 (3.9) %, P < 0.001). Using intention-to-treat analysis among 37 patients with AHI ≥10/h (CPAP group (n = 17) vs control group (n = 20)), there was no significant difference in Asthma Control Test score (CPAP 3.2 (2.7) vs control 2.4 (5.7), P = 0.568) but the CPAP group had a greater improvement in Epworth Sleepiness Scale (-3.0 (4.5) vs 0.5(3.8), P = 0.014), Asthma Quality of Life Questionnaire (0.6 (0.8) vs 0.02 (0.7), P = 0.022) and vitality domain in the SF-36 questionnaire (14.7 (16.8) vs 0.3 (16.2), P = 0.012) after 3 months. Data are presented as mean (SD) unless otherwise stated. CONCLUSION: A high prevalence of OSAS was found among patients with asthma and snoring. CPAP therapy for 3 months did not enhance asthma control but improved daytime sleepiness, quality of life and vitality.

Effects of CPAP therapy on visceral fat thickness, carotid intima-media thickness and adipokines in patients with obstructive sleep apnoea.

BACKGROUND AND OBJECTIVE: Obstructive sleep apnoea (OSA) is associated with an increased prevalence of metabolic syndrome. This study explores the effects of continuous positive airway pressure (CPAP) for patients with OSA on visceral and mesenteric fat thickness, carotid intima-media thickness (IMT) and adipokines. METHODS: A randomized controlled study was conducted at a teaching hospital on 90 patients newly diagnosed with OSA to receive either therapeutic CPAP or subtherapeutic CPAP for 3 months. Visceral fat thickness and carotid IMT were measured with B-mode ultrasound; adipokine levels were assessed at baseline and 3 months. RESULTS: Altogether, 45 patients received therapeutic CPAP and 45 received subtherapeutic CPAP without significant differences in age 50.3 (10.1) versus 48.7 (9.0) years, BMI 28.2 (3.9) versus 28.2 (4.5) kg/m2 , Epworth Sleepiness Scale (ESS) 12.4 (5.9) versus 11.3 (4.7), apnoea-hypopnoea index (AHI) 30.6 (21.4) versus 35.2 (25.5) /h, minimum SaO2 79.6 (10.8) versus 76.7 (12.4) % and existing co-morbidities. CPAP usage was therapeutic 4.2 (2.1) versus subtherapeutic 4.1 (2.0) h/night over 3 months. Adiponectin and irisin levels changed significantly following therapeutic CPAP for 3 months versus subtherapeutic CPAP (-1.6 vs 7.3, P = 0.042; 0.1 vs -0.1, P = 0.028 respectively) while only serum level of monocyte chemotactic protein 1 (MCP-1) at baseline was positively correlated with AHI (r = 0.278). No significant changes were observed in other adipokines, visceral fat thickness and IMT. CONCLUSION: Short-term therapeutic CPAP versus subtherapeutic CPAP does not significantly reduce visceral fat thickness and IMT, although it reduces adiponectin and increases irisin.

Mesenteric fat thickness is associated with metabolic syndrome independently of Apnoea-Hypopnoea Index in subjects with obstructive sleep apnoea.

BACKGROUND AND OBJECTIVE: Mesenteric fat thickness (MFT) was associated with metabolic syndrome (MetS) and obstructive sleep apnoea (OSA) in separate studies. This study aimed to assess whether the association of MFT with MetS was independent of OSA in subjects with suspected OSA. METHODS: Two hundred forty-two subjects (men: 181; women: 61) with suspected OSA underwent ultrasound examinations for measurements of mesenteric, subcutaneous and preperitoneal fat thicknesses after overnight polysomnography. Anthropometric measurements and metabolic risk profile were assessed. RESULTS: Two hundred twenty-one (91%) subjects were confirmed to have OSA with Apnoea-Hypopnoea Index (AHI) >5/h. MFT had significant correlation (P < 0.01) with AHI and most MetS components. In partial correlation with adjustment for AHI, MFT had significant correlation (P < 0.01) with most MetS components including fasting plasma glucose (r = 0.25), triglycerides (r = 0.24), HDL cholesterol (r = -0.29) and waist circumference (r = 0.56). In multivariate logistic regression with adjustments for the confounding variables including AHI, MFT was the only variable independently associated with MetS, with the odds ratio of 5.48 (95% CI: 1.5-20.0) for every 1 cm increase of MFT. When the subjects were subdivided into obese (BMI ≥ 27.5 kg/m(2) ) and non-obese (BMI < 27.5 kg/m(2) ) groups, the positive association of MFT with MetS persisted in the non-obese group only, with the odds ratio of 22 (95% CI 2.8-174.1) for every 1 cm increase of MFT. The AHI had significant association with MetS in male subjects only. CONCLUSION: MFT, rather than AHI, is the major independent determinant of MetS in subjects with suspected OSA, particularly in non-obese subjects. See Editorial, page 408.

Prevalence of obstructive sleep apnea syndrome and CPAP adherence in the elderly Chinese population.

BACKGROUND: This study assessed the prevalence of obstructive sleep apnea syndrome (OSAS) and CPAP adherence in the elderly Chinese in Hong Kong. METHODS: We conducted a sleep questionnaire survey among the elders aged ≥60 years in the community centres followed by level 3 home sleep study (Embletta). Subjects with an apnea hypopnea index (AHI) ≥ 15/hr alone and those with AHI ≥ 5/hr plus either cardiovascular risk factors or Epworth Sleepiness Score (ESS) ≥ 10 were offered CPAP treatment. RESULTS: Altogether 819 subjects were interviewed with mean (SD) age of 73.9 (7.5) years, BMI 24.2 (3.6) kg/m2, neck circumference 34.9 (3.4) cm and ESS 6.6 (5.2). Daytime sleepiness was reported by 72.4%, snoring loudly 5.1% and witnessed apnea 4%. Among 234 subjects who underwent home sleep study, 156 (66.7%), 102 (43.6%), 70 (29.9%) and 45 (19.2%) had AHI ≥ 5, ≥ 10, ≥ 15 and ≥ 20/hr respectively, with the prevalence increasing with age and BMI. In the sample, 149 subjects (63.7%) were classified as having OSAS, as defined by an AHI ≥ 5/hr with associated symptoms, involving 81 men (74.3%) and 68 women (54.4%). Neck circumference and snoring frequency were the only positive independent factors associated with the AHI and the diagnosis of OSAS. Among 141 subjects who were offered CPAP treatment, 30 accepted CPAP prescription with improvement of ESS and cognitive function over 12 months with CPAP usage of 4.2 (2.2) h/night. CONCLUSION: This study showed a high prevalence of OSAS among the community elders in Hong Kong. Home CPAP acceptance was low but there was significant improvement of subjective sleepiness and cognitive function among those on CPAP treatment.

A Randomized Controlled Study to Examine the Effect of a Lifestyle Modification Program in OSA.

BACKGROUND: Obesity is an important risk factor for OSA. This study aimed to assess the effect of weight reduction through a lifestyle modification program (LMP) on patients with moderate to severe OSA. METHODS: This was a parallel group, randomized controlled trial. Altogether, 104 patients with moderate to severe OSA diagnosed on portable home sleep monitoring were randomized to receive a dietician-led LMP or usual care for 12 months. The primary outcome was reduction of apnea-hypopnea index (AHI) at 12 months as assessed by portable home sleep monitoring. RESULTS: In the intention-to-treat analysis (ITT), LMP (n = 61) was more effective in reducing AHI from baseline (16.9% fewer events in the LMP group vs 0.6% more events in the control group, P = .011). LMP was more effective in reducing BMI (-1.8 kg/m2, 6.0% of the initial BMI; -0.6 kg/m2, 2.0% of the initial BMI in control group; P < .001). The reduction in daytime sleepiness as assessed by Epworth Sleepiness Scale was not significant in ITT but was more in the LMP group (-3.5 in the LMP group vs -1.1 in the control group, P = .004) by treatment per protocol analysis. There was modest improvement in mental health in the Short Form Health Survey. Eating behavior was improved with increased intake of protein and fiber. These changes were observed 4 months after the initial intensive diet counseling and persisted at 12 months. CONCLUSIONS: LMP was effective in reducing the severity of OSA and daytime sleepiness. The beneficial effect was sustained in 12 months. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT01384760; URL: www.clinicaltrials.gov.

COPD care programme can reduce readmissions and in-patient bed days.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a common disease worldwide with significant morbidity and mortality. AIM: To investigate the effect of a comprehensive COPD management programme in decreasing COPD readmissions 1 year before and 1 year after the programme. METHOD: 185 (166 males) patients admitted for acute exacerbation of COPD (AECOPD) were recruited between September 2010 and December 2012. COPD care team provided crisis support and maintenance therapy for the COPD patients for a total of 16 weeks. The protocol included COPD clinic run by respiratory physicians, COPD education and nurse clinics by respiratory nurses, out-patient pulmonary rehabilitation programme by physiotherapists, fast track doctor's clinic, telephone hotline for patients and nurse telephone calls to patients. Readmissions over a period of 1 year were assessed. RESULTS: The mean (SD) age of the subjects and FEV1 % predicted normal were 76.9 ± 7.37 yrs and 44.4 ± 20.7% respectively. 40 (21.6%) patients required non-invasive positive pressure ventilation during the recruitment admission. Admissions for AECOPD decreased from 2.39 ± 2.05 one year before programme to 1.65 ± 2.1 one year after programme (mean difference 0.75 ± 2.11 episodes, p < 0.001). The length of hospital stay was reduced from 12.17 ± 9.14 days one year before programme to 9.09 ± 12.1 days one year after the programme (mean difference 3.09 ± 12.1 days, p < 0.001). The FEV1 percentage predicted and quality of life measured by St George's Respiratory Questionnaire showed no significant improvement at 16 weeks after recruitment into the programme as compared to at 6 weeks. CONCLUSION: COPD care programme is effective in decreasing readmissions and length of hospital day for COPD patients.

Mesenteric fat thickness is associated with increased risk of obstructive sleep apnoea.

BACKGROUND AND OBJECTIVE: Mesenteric fat is a type of intraperitoneal adipose tissue draining into portal circulation. The objective of this study was to investigate the relationships between mesenteric fat thickness and obstructive sleep apnoea (OSA) in patients with suspected OSA. METHODS: One hundred forty-nine subjects (men: 114; women: 35) with suspected OSA underwent ultrasound examinations of mesenteric, preperitoneal and subcutaneous fat thickness after overnight polysomnography. Body mass index (BMI) and neck circumference were recorded. RESULTS: The subjects with OSA (n = 130, apnoea/hypopnoea index (AHI) >5/h) had greater neck circumference, higher BMI, and greater mesenteric and preperitoneal fat thickness than those without OSA (n = 19, AHI ≤ 5/h). There was positive correlation of AHI with mesenteric (r = 0.43, P < 0.001) and preperitoneal fat thickness (r = 0.3, P < 0.001), whereas no significant association was observed between AHI and subcutaneous fat thickness (r = 0.09, P = 0.27). On multivariate logistic regression, after adjustments for gender, age, BMI, neck circumference, and preperitoneal and subcutaneous fat thickness, the mesenteric fat thickness had a positive association with the presence of moderate OSA and severe OSA, with odds ratios of 7.18 and 7.45 for every 1 cm increase in mesenteric fat thickness when AHI was defined as ≥15/h and AHI ≥ 30/h, respectively. CONCLUSIONS: Mesenteric fat thickness is associated with increased risk of OSA, independent of other abdominal fat thickness, BMI and neck circumference. Sonographic measurement is potentially a useful tool for further evaluating the complex association of visceral fat, metabolic syndrome and OSA.

Evaluation of the asthma control test: a reliable determinant of disease stability and a predictor of future exacerbations.

BACKGROUND AND OBJECTIVE: This study assessed the asthma control test (ACT) cut-off values for asthma control according to the Global Initiative for Asthma guideline in adults and the effectiveness of ACT scores in predicting exacerbations and serial changes in ACT scores over time in relation to treatment decisions. METHODS: Subjects completed ACT together with same-day spirometry and fractional concentration of exhaled nitric oxide (FeNO) measurement at baseline and at 3 months. Physicians, blinded to the ACT scores and FeNO values, assessed the patient's asthma control in the past month and adjusted the asthma medications according to management guidelines. Asthma exacerbations and urgent health-care utilization (HCU) at 6 months were recorded. RESULTS: Three hundred seventy-nine (120 men) asthmatics completed the study. The ACT cut-off for uncontrolled and partly controlled asthma were ≤19 (sensitivity 0.74, specificity 0.67, % correctly classified 69.5) and ≤22, respectively (sensitivity 0.73, specificity 0.71, % correctly classified 72.1). Baseline ACT score had an odds ratio of 2.34 (95% confidence interval: 1.48-3.69) and 2.66 (1.70-4.18) for urgent HCU and exacerbations, respectively, at 6 months (P < 0.0001). However, baseline FeNO and spirometry values had no association with urgent HCU and exacerbations. The 3-month ACT score of ≤20 correlated best with step-up of asthma medications (sensitivity 0.65, specificity 0.81, % correctly classified 72.8). For serial changes of ACT scores over 3 months, the cut-off value was best at ≤3 for treatment decisions with low sensitivity (0.23) and % correctly classified (57.3%) values. CONCLUSIONS: Single measurement of ACT is useful for assessing asthma control, prediction of exacerbation and changes in treatment decisions.

A longitudinal study of serial BODE indices in predicting mortality and readmissions for COPD.

INTRODUCTION: BODE index comprises Body mass index, Obstruction of the airway [FEV(1)], Dyspnoea score [modified Medical Research Council questionnaire] and Exercise capacity [6 min walk test]. This study assessed the role of serial changes in BODE index in predicting mortality and readmissions of COPD patients. METHODS: A prospective cohort study involving 243(208 males) COPD patients hospitalized for acute exacerbations of COPD [AECOPD]. BODE index was assessed at 6 weeks(baseline), 6, 12, 18 and 24 months post hospital discharge. Mortality and readmissions in the subsequent 3 years were recorded. All the patients were managed by usual care without additional intervention. RESULTS: The mean (SD) age and FEV(1)% predicted were 74.2(7.8) yrs and 51.7(21.6)% respectively. Over the 3 years, 25.1% died whereas 76.5% had at least 1 readmission for AECOPD. Baseline BODE index was predictive of both the survival and readmissions to hospital for AECOPD by Cox regression analysis (p < 0.001 for both survival and readmissions). Over 24 months, 71(40.1%), 94(53.1%), 12(6.8%) patients had increased (>1 point), no change, and decreased in BODE (>1 point) index respectively. Serial changes in BODE index at 6 month was marginally associated with mortality, but not at 12-, 18- and 24-month. The 6-, 12- and 24-month BODE indices were predictive of the readmissions for AECOPD when compared to baseline. CONCLUSION: Baseline BODE index could predict both survival and readmissions for AECOPD, whereas serial BODE indices were not predictive of survival at 3 years. Single rather than serial measurements of BODE index is sufficient for prediction of survival and readmissions for patients treated with usual care.

Validation of Embletta portable diagnostic system for identifying patients with suspected obstructive sleep apnoea syndrome (OSAS).

UNLABELLED: The Embletta portable diagnostic system is highly sensitive and specific in quantifying the AHI and differentiating obstructive and supine events when compared against hospital-based PSG in patients with suspected OSAS. The simple device may be useful for screening and diagnostic purpose when access to PSG is limited. BACKGROUND AND OBJECTIVES: This study aimed to evaluate the diagnostic accuracy of Embletta portable diagnostic system (PDS, Medcare, Reykjavik, Iceland) for the screening of sleep apnoea in clinical practice. METHODS: The Embletta PDS is a digital three-channel recording device that measures airflow through a nasal cannula connected to a pressure transducer, oxygen saturation plus both respiratory and abdominal movements via built-in effort and body position sensors. An AHI is determined based on recording time. Nocturnal polysomnography (Alice 4, Healthdyne, Atlanta, USA), with airflow measured by a nasal pressure transducer (PTAF2, Pro-Tech, Woodinville, WA, USA)) and Embletta PDS recordings, was performed simultaneously in consecutive patients with suspected OSA syndrome. The PSG recordings were analysed manually by a blinded investigator. RESULTS: Ninety subjects were recruited and 10 failed Embletta PDS studies due to measurement failure. Among the remaining 80 subjects, 63 were males. The mean age (SD) was 51.4 (11.9) years old, BMI 27.1(4.2) kg/m2, neck circumference 38.6 (3.6) cm and Epworth Sleepiness Score 9.7 (5.3). The AHI obtained by the Embletta PDS correlated closely with that obtained by PSG (Pearson correlation, r=0.979, P<0.001). Comparison of AHI based on the Embletta PDS against the PSG demonstrated high sensitivity at AHI>or=5/h (sensitivity 0.924 and specificity 0.857) and high specificity at AHI>or=20/h (sensitivity 0.853 and specificity 0.957). CONCLUSIONS: The Embletta PDS is a highly sensitive and specific screening device in quantifying AHI when compared against PSG in patients with suspected OSA syndrome.

A one-year prospective study of infectious etiology in patients hospitalized with acute exacerbations of COPD and concomitant pneumonia.

AIM: This study assessed the infectious etiology of patients hospitalized for acute exacerbations of chronic obstructive pulmonary disease (AECOPD) with concomitant pneumonia. METHODS: Patients admitted to medical wards in an acute hospital were recruited prospectively from May 1, 2004 to April 30, 2005. Sputum culture, blood culture, paired serology, and nasopharyngeal aspirates (NPA) viral culture and polymerase chain reaction (PCR) studies were performed. Spirometry was assessed in stable phase at 2-3 months post-hospital discharge. RESULTS: Seventy eight subjects were admitted for AECOPD with concomitant pneumonia. The mean (SD) age was 77.1 (7.5) years, with FEV(1) of 41.5 (20.8)% predicted normal. Overall, an infectious etiology could be established in 48.7% of the subjects. Among the 71 subjects with sputum collected, 40.8% had positive bacterial culture. The commonest bacteria identified were Streptococcus pneumoniae (8[11.3%]), Pseudomonas aeruginosa (7[9.9%]) and Haemophilus influenzae (7[9.9%]). Among the 66 subjects with NPA collected, 9.0 and 12.2% had positive viral culture and PCR results, respectively. The commonest viruses identified by NPA PCR were influenza A (4[6.1%] subjects) and rhinovirus (2[3.0%]). Paired serology was positive in 4.4%. Patients on high dose inhaled corticosteroid (ICS) (>1000 mcg beclomethasone-equivalent/day) had a higher rate of positive sputum bacterial culture than those on low-medium dose of ICS (50.0% vs 18.2%, p=0.02). CONCLUSION: An infectious etiology could be established in about half of patients hospitalized with AECOPD and concomitant pneumonia. The majority of identifiable causes were bacterial. Patients on high dose ICS might have impaired airway defense as reflected by the higher rate of positive sputum culture.

Viral etiology of acute exacerbations of COPD in Hong Kong.

INTRODUCTION: Viral respiratory infections may precipitate acute exacerbations of COPD (AECOPD). However, little is known about viral etiology related to AECOPD in Asia. We aimed to study the viral etiology of AECOPD in Hong Kong. METHODS: Patients admitted to an acute hospital in Hong Kong with AECOPD were recruited prospectively from May 1, 2004, to April 30, 2005. Nasopharyngeal aspirate was collected and assessed by polymerase chain reaction (PCR) and viral culture. Spirometry was performed in the stable phase at 2 to 3 months after hospital discharge. RESULTS: There were 262 episodes of AECOPD among 196 patients (mean age, 75.7 +/- 7.7 years [+/- SD]; 160 men). Mean FEV(1) was 39.6 +/- 18.9% of predicted normal, and FEV(1)/FVC ratio was 58.0 +/- 15.2%. Fifty-eight episodes (22.1%) yielded positive viral PCR results. The viruses identified were influenza A (7.3%), coronavirus OC43 (4.6%), rhinovirus (3.1%), influenza B (2.7%), and respiratory syncytial virus (2.3%). The diagnostic yield of viral identification by PCR was 2.7 times higher than that based on conventional viral culture. The rates of identifying a positive viral etiology by PCR were similar among the subjects with FEV(1) >or= 50%, >or= 30 to 50%, and < 30% of predicted normal. Viral infection appeared to have no effect on subsequent readmissions or mortality rate over a study period of 1 year CONCLUSION: Influenza A and two less-attended viruses, coronavirus OC43 and rhinovirus, were the common etiologic agents in patients hospitalized with AECOPD in Hong Kong. These should be considered in developing diagnostic and intervening strategies pertaining to AECOPD.