Tat-On Chan

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

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.

Dietary fibre intake and constipation in children with severe developmental disabilities

Objective: Constipation is a common problem in children with severe developmental disabilities (DD). This study aimed to evaluate fibre intake of severe DD children living in a residential institution, and the possibility of reducing the use of laxatives by increasing their fibre intake.

A prospective cohort study of the long-term effects of CPAP on carotid artery intima-media thickness in Obstructive sleep apnea syndrome

ObjectiveTo examine the long-term effect of CPAP on carotid artery intima-media thickness (IMT) in patients with Obstructive sleep apnea syndrome(OSAS).MethodsA prospective observational study over 12 months at a teaching hospital on 50 patients newly diagnosed with OSAS who received CPAP or conservative treatment (CT). Carotid IMT was assessed with B-mode Doppler ultrasound from both carotid arteries using images of the far wall of the distal 10 mm of the common carotid arteries at baseline, 6 months and 12 months.Measurements and results [mean (SE)]Altogether 28 and 22 patients received CPAP and CT respectively without significant differences in age 48.8(1.8) vs 50.5(2.0)yrs, BMI 28.2(0.7) vs 28.0(1.2)kg/m2, ESS 13.1(0.7) vs 12.7(0.6), AHI 38(3) vs 39(3)/hr, arousal index 29(2) vs 29(2)/hr, minimum SaO2 75(2) vs 77(2)% and existing co-morbidities. CPAP usage was 4.6(0.3) and 4.7(0.4)hrs/night over 6 months and 1 year respectively. Carotid artery IMT at baseline, 6 months, and 12 months were 758(30), 721(20), and 705(20)micron for the CPAP group versus 760(30), 770(30), and 778(30)micron respectively for the CT group, p = 0.002.Among those free of cardiovascular disease(n = 24), the carotid artery IMT at baseline, 6 months and 12 months were 722(40), 691(40), and 659(30)micron for the CPAP group (n = 12) with usage 4.5(0.7) and 4.7(0.7) hrs/night over 6 months and 12 months whereas the IMT data for the CT group(n = 12) were 660(20), 685(10), and 690(20)micron respectively, p = 0.006.ConclusionsReduction of carotid artery IMT occurred mostly in the first 6 months and was sustained at 12 months in patients with reasonable CPAP compliance.

Relationship of urinary sodium/potassium excretion and calcium intake to blood pressure and prevalence of hypertension among older Chinese vegetarians

Objective: To examine the associations of dietary sodium and potassium, as reflected by the urinary sodium/potassium excretion, and calcium intake with blood pressure and the prevalence of hypertension among older Chinese vegetarians in Hong Kong.Design: Cross-sectional study.Setting: Research clinic in a teaching hospital in Hong Kong.Subjects: A total of 111 ambulatory vegetarians over the age of 55 were recruited from members of religious organizations or old age hostels.Main outcome measures: Hypertension was defined as supine blood pressure >140/90 mmHg or a history of hypertension. Dietary sodium, potassium and calcium intakes were assessed by 24 h recall method or fasting urinary sodium or potassium/creatinine ratios.Results: Seventy-one subjects (64%) were found to have hypertension. Compared with normotensive subjects, hypertensive subjects had lower calcium intake (411±s.d. 324 vs 589±428 mg, P=0.04), but higher urinary sodium/creatinine ratio (32.6±19.3 vs 21.0±12.4, P=0.00) and sodium/potassium ratio (4.7±2.8 vs 3.4±2.3, P=0.02). Among 88 subjects not taking diuretics or antihypertensive drugs, systolic blood pressure was related to calcium intake (r=−0.40), urinary sodium/creatinine ratio (r=0.39), urinary sodium/potassium ratio (r=0.30) and age (r=0.23). Diastolic blood pressure was related to urinary sodium/creatinine (r=0.29). Twenty-three subjects with high urinary sodium/potassium and low calcium intake and 16 subjects with low urinary sodium/potassium ratio and high calcium intake differed markedly with respect to systolic blood pressure (159±26 vs 130±15 mmHg) and prevalence of hypertension (78% vs 25%).Conclusion: Older Chinese vegetarians are predisposed to hypertension because of their sodium-rich but calcium-deficient diets.

Validation study of a portable monitoring device for identifying OSA in a symptomatic patient population.

Background and objective:  Obstructive sleep apnoea syndrome (OSAS) is a common disorder associated with early atherosclerosis, diabetes mellitus, ischaemic heart disease and cerebrovascular disease. The gold standard for confirming OSAS is based on an attended overnight polysomnography (PSG) in a sleep laboratory; however lack of health‐care resources creates long waiting times for patient access to this diagnostic test. This study evaluated the ability of a portable sleep‐monitoring device to identify patients in Hong Kong with suspected OSAS.

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.

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.

CHILDHOOD POISONING IN HONG KONG: EXPERIENCE OF THE DRUG AND POISONS INFORMATION BUREAU FROM 1988 TO 1992

Dr Cox (J. Paediatr. Child Health 1994; 30: 191 -2) will be pleased to know that the National Health and Medical Research Council (NH &MRC) has recommended that we adopt a two-dose strategy for measles, mumps, rubella (MMR) vaccine in 1994. The first dose is to be given to all children at the age of 12 months. The second dose will replace the existing rubella vaccination programme for teenage girls and is scheduled for all boys and girls aged 10-1 6 years. The vaccine will be supplied free to the States from July 1994. Some States have already made this change in the schedule, others are waiting to implement it after July 1. In 1993, nearly 4400 cases of measles were notified in Australia. This is by far the highest number for many years. Dr Cox was concerned about the proportion of teenagers among these cases and about the possibility of waning vaccine-induced immunity. While this may be responsible for some cases, by far the majority of cases of measles in Australia occur in children who have never been vaccinated. The introduction of the second dose of vaccine should not divert attention from the importance of increasing compliance for the first dose of MMR, which should be given promptly at the age of 12 months. Measles still has its highest morbidity and mortality in younger children. In the USA, in 1989, although only 37% of cases occurred in children under the age of 5 years, these caused 70% of the deaths.’ The new two-dose strategy for MMR is important and timely. However, we could just complacently revaccinate the vaccinated! More attention must be given to targeting immunization services to children who are disadvantaged. Immunization histories should be checked at every health care visit and deficiencies updated ‘on the spot’2 Health care providers should be familiar with the real contraindications to immunization and should not allow trivial reasons to postpone doses. One-third of the children presenting with measles in recent large measles outbreaks in the USA had had health care visits in the previous 6 weeks in which an opportunity had been missed to immunize them; these cases could have been p r e ~ e n t e d . ~ . ~ It is very likely that this is also occurring in Australia.

A randomized controlled trial of an ambulatory approach versus the hospital-based approach in managing suspected obstructive sleep apnea syndrome

Comparisons of home-based versus hospital-based approach in managing patients with suspected obstructive sleep apnoea syndrome(OSAS). A prospective, controlled CPAP parallel study of new referrals with suspected OSAS randomized into group A) home-based or B) hospital-based approach. Following detection of AHI ≥ 15/hr by Embletta sleep study (group A) or polysomnography (group B), patients received CPAP for 3 months after an overnight autoCPAP titration at home or in hospital respectively. Modified intention-to-treat analysis of those with AHI ≥ 15/hr on CPAP (n = 86 vs 86) showed no difference in Epworth sleepiness score, the primary endpoint, but greater improvement in Sleep-Apnoea-Quality-of-Life-Index[difference 0.3,(95%CI 0.02, 0.6), p = 0.033] at 3 months in group A. The mean costs for the patients in group A and group B were HK

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

8479(989) and HK