Prevalence of snoring and sleep-disordered breathing in a group of commercial bus drivers in Hong Kong

Objectives: To assess the prevalence of sleep‐­disordered breathing (SDB) and its associated symptoms in a group of commercial bus drivers in Hong Kong. Methods: Two hundred and sixteen of 410 bus drivers from three different shifts were interviewed with the Sleep & Health Questionnaire (SHQ) and the Epworth sleepiness scale (ESS) at a Hong Kong bus depot. Seventeen subjects from each shift were then randomly selected for at‐home sleep study using the Mesam IV device (Madaus Medizin?Elektronik, Freiburg, Germany). Results: There were 207 men and nine women (mean age 42.4 ± 7.5 years; body mass index (BMI) 25.4 ± 4.5 kg/m²; ESS 5.3 ± 4.2). From the SHQ it was discovered that: (i) daytime sleepiness was reported by 87 subjects (40%), (ii) snoring ≥ 3 times per week was reported by 80 subjects (37%), (iii) witnessed apnoea was reported by 17 subjects (7.9%) and (iv) 29 subjects (13.4%) reported having fallen asleep during driving. Among the 51 subjects who underwent the at‐home sleep study: (i) 31 subjects (61%) had respiratory disturbance index (RDI) ≥ 5 per hour of sleep, (ii) 21 subjects (41%) had RDI ≥ 10 per hour of sleep, (iii) 12 subjects (24%) had RDI ≥ 15 per hour of sleep and (iv) 35 subjects (68.6%) snored objectively ≥ 10% of the night. Ten subjects (20%) had RDI ≥ 5 and sleepiness at work, while five subjects (9.8%) had RDI ≥ 5 and ESS > 10. No significant differences were noted in the SHQ responses, ESS, objective snoring or RDI among the three groups. Multiple regression analysis showed that BMI and witnessed apnoea were the only positive independent predictors of RDI. Conclusions: This study showed a high prevalence of objective snoring and SDB in a group of commercial bus drivers. Neither self‐reported sleepiness nor the ESS could identify subjects with SDB. (Intern Med J 2002; 32: 149?157)     

High prevalence of previously unknown subclinical hypothyroidism in obese patients referred to a sleep clinic for sleep disordered breathing

BACKGROUND AND AIM: To evaluate the prevalence of previously unknown hypothyroidism in adult male and female patients with a wide range of body mass index (BMI) values, referred to a Sleep Clinic because of sleep disordered breathing (SDB). METHODS AND RESULTS: Serum concentrations of thyroid stimulating hormone (TSH) and free thyroxin (fT4), as well as forced vital capacity (FVC), PaO2, PaCO2, the Epworth sleepiness scale (ESS), respiratory disturbance index (RDI), loud snoring, and the percentage of total sleep time (TST) with <90% oxyhemoglobin saturation (TST(saO2<90%)) were measured in 78 overweight and obese adult subjects with no previous diagnosis of hypothyroidism (age: 18-72 years). The prevalence of previously undiagnosed subclinical hypothyroidism in the population as a whole was 11.5%. BMI, TSH and ESS were significantly higher in the hypothyroid than the euthyroid subjects, but there was no significant between-group difference in RDI, TST(saO2<90%) or the other investigated variables, including the prevalence of obstructive sleep apnea (OSA). Among the hypothyroid individuals, BMI, neck circumference, ESS, RDI and TST(Sao2<90%) were significantly higher in those with than in those without OSA. Furthermore, there was a clear trend towards a lower FVC% and higher snoring score in the OSA patients. CONCLUSIONS: Our results demonstrate a higher prevalence of hypothyroidism than that commonly reported in overweight and obese individuals referred to a Sleep Clinic for polysomnography because of SDB, thus suggesting that thyroid function should be evaluated in all obese patients suffering from SDB despite economic concerns.     

A community study of sleep-disordered breathing in middle-aged Chinese men in Hong Kong

BACKGROUND: Sleep-disordered breathing (SDB) in Asian populations is being increasingly recognized. This study investigated the prevalence of SDB in Chinese middle-aged office-based male workers in Hong Kong. METHODS: Sleep questionnaires were distributed to 1,542 men (age range, 30 to 60 years), and 784 questionnaires were returned. Subsequently, full polysomnographic (PSG) examinations were conducted in 153 questionnaire respondents. Subjects with an apnea-hypopnea index (AHI) > or =5 were recalled for clinical assessment. RESULTS: Questionnaire respondents were similar in age and body mass index (BMI) to the general community in the target age range and gender. Habitual snoring was reported by 23% of this cohort and was associated with excessive daytime sleepiness (EDS), hypertension, witnessed abnormal breathing pattern, BMI, and leg movements during sleep. Allowing for subject bias in undergoing PSG, the estimated prevalence of SDB and obstructive sleep apnea syndrome (OSAS) (defined as SDB in the presence of EDS) at various AHI cutoff threshold values was 8.8% and 4.1% (AHI > or =5), 6.3% and 3.2% (AHI > or =10), and 5.3% and 3.1% (AHI > or =15). Multiple stepwise logistic regression analysis identified BMI, habitual snoring, time taken to fall asleep, and age as predictors of SDB at AHI > or =5. Analysis of anthropometric parameters indicated that the relative risk of OSAS attributable to obesity was less than in white subjects. CONCLUSION: This community-based study of sleep apnea among middle-aged men in Hong Kong using full PSG demonstrated an estimated prevalence of OSAS (AHI > or =5 and EDS) at 4.1%. Increasing BMI and age were associated with SDB, although factors other than adiposity may also have an important pathogenic role in OSA in Chinese subjects.     

A community study of sleep-disordered breathing in middle-aged Chinese women in Hong Kong: prevalence and gender differences

STUDY OBJECTIVES: To investigate the prevalence of sleep-disordered breathing (SDB) and obstructive sleep apnea syndrome (OSAS) in community-based, middle-aged Chinese women, and to compare the differences between gender with a similar study in men. DESIGN: A cross-sectional study conducted in Hong Kong from 1998 to 2000. SETTING: Sleep questionnaires were distributed to women (30 to 60 years old) in three offices and two community centers. All were invited to undergo full polysomnography in a sleep laboratory. PARTICIPANTS: Questionnaires were distributed to 1,532 women, and 854 questionnaires were returned. Polysomnography was conducted in 106 respondents. Measurements and results: Conservative estimated prevalence of SDB (apnea-hypopnea index [AHI] > = 5) and OSAS (AHI > or = 5 plus excessive daytime sleepiness [EDS]) were 3.7% and 2.1%, respectively. Age-specific prevalence of OSAS was 0.5%, 2.2%, and 6.1% in the 30- to 39-year-old, 40- to 49-year-old, and 50- to 60-year-old age groups, respectively. Stepwise multiple logistic regression analysis identified body mass index (BMI) and age as predictors of SDB. Compared to Chinese men, the prevalence of SDB and OSAS in women was lower, but the gender difference decreased with age. The AHI of affected women was also significantly lower despite comparable BMI. Compared to men, women with SDB had same degree of self-reported snoring and a similar degree of EDS despite the lower AHI. CONCLUSIONS: This study demonstrated an estimated prevalence of OSAS at 2.1% among middle-aged Chinese women in Hong Kong, with a 12-fold rise from the fourth to the sixth decade of life. BMI and age were significant independent predictors of SDB. Compared to men, women with SDB had lower AHIs, despite similar BMIs.     

Changes in cognitive function associated with sleep disordered breathing in older people

OBJECTIVES: Sleep disordered breathing (SDB) is very common in older people and is known to be associated with complaints of impaired daily functioning, including excessive daytime sleepiness and cognitive impairments. As part of a larger study on SDB and aging, it became possible to examine the relationship between SDB and cognition in older men and women. DESIGN: A population-based longitudinal study. SETTING: In-home interviews and home sleep recordings in the greater San Diego area. PARTICIPANTS: Community-dwelling people age 65 and older with high risk for SDB were originally studied from 1981 through 1985 and then followed every 2 years. Data from the 46 subjects who completed Visit 3 and Visit 4 are presented. MEASUREMENTS: Subjects were interviewed in the home about their sleep and medical condition before each visit. Cognitive function was assessed using the Mini-Mental State Examination (MMSE). Daytime sleepiness was based on self-report. Objective sleep was recorded in the home and scored for sleep, apneas and hypopneas, and oximetry variables. RESULTS: Increases in respiratory disturbance index (RDI) (P= .036) and increases in daytime sleepiness (P= .002) were associated with decreases in cognitive performance (i.e., increases in cognitive impairment). Increases in RDI were also associated with increases in daytime sleepiness (P= .012). Change in MMSE scores was therefore regressed onto changes in RDI, daytime sleepiness, age, and education, resulting in decreases in MMSE scores being associated with increases in daytime sleepiness (P= .019) but not with changes in RDI (P= .515). There was no significant relationship between changes in oxygen saturation levels and changes in MMSE. CONCLUSIONS: The results of this study suggest that declining cognitive function is associated primarily with increases in daytime sleepiness. Although cognitive decline was also associated with increases in RDI, this association did not hold in the more inclusive model which also included variable of SDB, oximetry, sleep and subjective report. One theoretical model could suggest that any relationship between SDB and cognitive function may be mediated by the effect of SDB on daytime sleepiness. These results suggest that older patients suffering from mild to moderate SDB may benefit from the treatment of SDB, even if they are not markedly hypoxemic.     

Prevalence of sleep-disordered breathing and continuous positive airway pressure compliance: results in chinese patients with first-ever ischemic stroke

OBJECTIVE: To assess the prevalence of sleep-disordered breathing (SDB), continuous positive airway pressure (CPAP) acceptance, and CPAP compliance in patients who have experienced ischemic stroke. DESIGN: A case-controlled study. SETTING: A university hospital. MEASUREMENTS AND RESULTS: We recruited 23 women and 28 men, who were admitted to the hospital within 4 days of stroke onset, with a mean (+/- SD) age of 64.2 +/- 13.0 years and a body mass index (BMI) of 24.3 +/- 4.4 kg/m(2) for this study. Twenty-seven patients (53%) and 9 patients (17.6%), respectively, reported a history of snoring and severe daytime sleepiness prior to experiencing a stroke, while the mean Epworth sleepiness scale score was 6.8 +/- 3.6. Polysomnography revealed 34 patients (67%) with an apnea-hypopnea index (AHI) of > or = 10 events per hour, 31 patients (61%) with an AHI of > or = 15 events per hour, and 25 patients (49%) with an AHI of > or = 20 events per hour. Significant obstructive SDB, defined as an AHI of > or = 20/h, was more prevalent in ischemic stroke patients than in control subjects (49% vs 24%, respectively; p = 0.04) and was associated with a higher BMI (p = 0.046). Among the 34 patients with an AHI of > or = 10/h, CPAP titration was tolerated by 16 patients, but only 4 patients who had typical sleep apnea features proceeded to home CPAP treatment with objective compliance over a period of 3 months of 2.5 +/- 0.6 h per night. A subgroup of 20 patients not receiving CPAP showed partial spontaneous improvement of SDB at 1 month (baseline AHI, 32.3 +/- 17.6 events per hour; AHI at 1 month, 23.0 +/- 18.8 events per hour; p = 0.01) with a trend toward improvement for the obstructive but no significant change for the central events, whereas no improvement in AHI was noted for the four patients receiving CPAP. CONCLUSION: There is a high prevalence of obstructive SDB in patients who have experienced acute ischemic stroke, which, in many cases, is different from classic obstructive sleep apnea syndrome, and this is reflected by the lack of significant sleepiness, poor CPAP acceptance, and partial spontaneous improvement at 1 month.     

Prevalence of sleep abnormalities and their association with metabolic syndrome among Asian Indians: Chennai Urban Rural Epidemiology Study (CURES-67)

Objective

To estimate the prevalence of sleep abnormalities and their association with glucose intolerance and metabolic syndrome (MS) in the normal-weight urban South Indian population.

Methods

This population-based, cross-sectional study was carried out in 358 subjects aged 20–76 years randomly selected from the Chennai Urban Rural Epidemiology Study in South India. A validated questionnaire assessing various sleep abnormalities (snoring, daytime sleepiness, lack of refreshing sleep, and number of hours of sleep) was administered. All subjects underwent an oral glucose tolerance test, and anthropometric biochemical measurements were obtained to assess cardiometabolic risk factors including glucose intolerance. Diabetes risk was assessed using a previously validated Indian Diabetes Risk Score (IDRS).

Results

The overall prevalence of snoring and daytime sleepiness was 40% and 59%, respectively. Snorers were more male, older, smokers, and had higher levels of cardiometabolic risk factors. Subjects with daytime sleepiness had higher body mass index (BMI) and abdominal obesity. Both snoring (50.9% vs 30.2%, p < 0.001) and daytime sleepiness (68% vs 49.7%, p < 0.001) were more prevalent among subjects with impaired glucose metabolism compared to those with normal glucose metabolism. Both sleep measures were associated with higher diabetes risk scores, as assessed by the IDRS (snoring: trend χ², 11.14, p = 0.001; daytime sleepiness: trend χ², 5.12, p = 0.024). Metabolic syndrome was significantly associated with snoring even after adjusting for age, sex, family history of diabetes, physical activity, smoking, and alcohol.

Conclusion

The prevalence of snoring and daytime sleepiness is high among urban South Indians and these two sleep measures are associated with glucose intolerance, MS, and higher diabetes risk scores.     

The effect of race and sleep-disordered breathing on nocturnal BP "dipping": analysis in an older population

STUDY OBJECTIVES: BP normally drops (or "dips") by approximately 10% at nighttime; however, in a number of illnesses there is an increased amount of "nondipping" of nocturnal BP. This study examined whether nondipping in older African Americans and older white subjects is related to the presence of sleep-disordered breathing (SDB) and hypertension. DESIGN: Prospective study with a convenience sample. SETTING: All data were collected in the subjects' homes. PARTICIPANTS: Seventy self-defined African Americans with complaints of snoring or excessive daytime sleepiness, and 70 age-matched and gender-matched white subjects. Measurements and results: Sleep was recorded for 2 nights, with 1 night of oximetry. BP was recorded on a separate 24-h period. African Americans had higher dipping ratios than white subjects even after accounting for covariates such as respiratory disturbance index (RDI), oxygen desaturation index (ODI), body mass index, and average 24-h mean arterial pressure (p = 0.025). Higher values of RDI (R(2) = 0.0686, p = 0.021) and ODI (R(2) = 0.042, p < 0.03) were correlated with higher dipping ratios in both African Americans and white subjects. However, there was a three-way interaction such that higher RDIs were correlated primarily with nondipping in African Americans receiving antihypertensive medication (R(2) = 0.0373, p = 0.022). CONCLUSIONS: These results demonstrated that African Americans tend to be "nondippers," while white subjects tended to be "dippers." This nondipping was not a result of weight, gender, or of having SDB. The analyses also confirmed that, in both races, the dipping ratio was greatest in those with SDB and hypertension. The third hypothesis, that RDI would be greatest in the nondipping hypertensive subjects, was true only for the African Americans.     

Sleep-related breathing disorders, loud snoring and excessive daytime sleepiness in obese subjects

OBJECTIVE: To investigate the prevalence of sleep breathing disorders, loud snoring and excessive daytime sleepiness in a group of obese subjects, and to identify the predictors of obstructive sleep apnea (OSA) severity in these patients. SUBJECTS: A total of 161 consecutive obese patients (body mass index (BMI)> or =30.0 kg/m(2)), ranging between 30.0 and 67.3, represented by 57 men and 104 women, aged 16-75 y. Forty (15 men and 25 women) age-matched (20-70 y) nonobese (BMI<27 kg/m(2)) volunteers were also recruited for the study. MEASUREMENTS: Respiratory function parameters, nocturnal sleep quality (evaluated by a specific questionnaire), nocturnal hypoventilation and OSA (evaluated by night polysomnography) were examined in all subjects. Anthropometric parameters (neck circumference, waist circumference, waist-to-hip ratio) were also investigated. RESULTS: Eighty-three obese patients (51.5% of the obese group) had a respiratory disturbance index (RDI)> or =10, corresponding to a moderate or severe sleep apnea. In particular, 24.8% (40/161), ie a quarter of all obese patients, were affected by severe OSA and this alteration was present in 42.1% of obese men (24/57) and in 15.4% (16/104) of obese women. When a stepwise multiple regression analysis was performed, neck circumference in men and BMI in women were shown to be the strongest predictors of sleep apnea. Twenty-nine percent of all obese subjects (40.3% of men and 23.1% of women) showed nocturnal hypoventilation; however, it was present as a unique breathing alteration in only 5% of the obese population. The percentage of patients having excessive daytime sleepiness was significantly higher than in nonobese subjects, even when only nonapneic obese patients were considered (P<0.001). CONCLUSION: This study shows that OSA is present in more than 50% of a population of obese patients with a mean BMI higher than 40.0, this percentage being much higher than that commonly reported in previous studies, particularly in women. Neck circumference in men and BMI in women seem to be the strongest predictors of the severity of OSA in obese patients. Nocturnal hypoventilation seems to be present in more than 29% of a severe obese population. Moreover, this study indicates that morbid obesity can be associated with excessive daytime sleepiness even in the absence of sleep apnea.     

Gender differences in the expression of sleep-disordered breathing : role of upper airway dimensions.

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is a common disorder that is characterized by repetitive episodes of upper airway narrowing and collapse. Obesity is a major risk factor for OSA. Compared with men, women have greater total body fat and are more obese, and yet the prevalence of OSA is much higher in men. The airway size and compliance and pharyngeal muscle tone are important determinants of upper airway patency during sleep. The discrepancy between greater frequency of obesity and lower prevalence of OSA in women has not been explained and suggests a different pathogenetic mechanism underlying this condition. Most clinical studies in OSA have either combined the sexes or have described results from men only. The object of this study was twofold: (1) to examine the effect of obesity on pharyngeal size in both men and women, and (2) to determine the role of upper airway dimensions in the expression of sleep-disordered breathing (SDB) and its relationship to gender. DESIGN: Prospective study of subjects referred for evaluation of SDB. SETTING: University-based sleep center. SUBJECTS: Seventy-eight male patients (mean +/- SE age, 49.2 +/- 1.5 years) and 52 female patients (mean age, 47.4 +/- 1.5 years). MEASUREMENTS AND RESULTS: All subjects underwent in-laboratory polysomnography with measurement of upper airway size using the acoustic reflectance method. Although the two groups were similar in age, the female patients were slightly heavier than the male patients (body mass index [BMI], 36.0 +/- 1.7 kg/m(2) vs 33.3 +/- 0.8 kg/m(2), respectively; p < 0.0001). Despite similar clinical presentation of snoring and excessive daytime sleepiness, women had mild OSA (respiratory disturbance index [RDI], 9.2 +/- 2.7 events per hour) or increased upper airway resistance syndrome compared with men with more severe OSA (RDI, 28.0 +/- 3.5 events per hour; p < 0.0001). In contrast, women had a significantly smaller oropharyngeal junction and pharynx than men (p < 0.02). Upper airway size correlated significantly with the severity of sleep apnea in men only. There was no correlation between BMI and pharyngeal size in either gender. CONCLUSIONS: This study demonstrates that the static properties of upper airway in awake men but not women correlate with the severity of sleep apnea. This suggests inherent structural and functional differences in upper airway during sleep between men and women with more favorable airway mechanics in women.     

Echocardiographic features of the right heart in sleep-disordered breathing: the Framingham Heart Study

The effect of sleep-disordered breathing (SDB) on right heart structure and function is controversial. Studies of patients referred for evaluation of possible sleep apnea have yielded conflicting results, and the impact of SDB on the right heart has not been investigated in the general population. We examined the echocardiographic features of subjects with SDB at the Framingham Heart Study site of the Sleep Heart Health Study. Of 1,001 polysomnography subjects, 90 with SDB defined as a respiratory disturbance index (RDI) score > 90th percentile (mean RDI = 42) were compared with 90 low-RDI subjects (mean RDI = 5) matched for age, sex, and body mass index. Right heart measurements, made without knowledge of clinical status, were compared between groups. The majority of the subjects were male (74%). After multivariable adjustment, right ventricle (RV) wall thickness was significantly greater (p = 0.005) in subjects with SDB (0.78 +/- 0.02 cm) than in the low-RDI subjects (0.68 +/- 0.02 cm). Right atrial dimensions, RV dimensions, and RV systolic function were not found to be significantly different between subjects with SDB and the low-RDI subjects. We conclude that in this community-based study of SDB and right heart echocardiographic features, RV wall thickness was increased in subjects with SDB. Whether the RV hypertrophy observed in persons with SDB is associated with increased morbidity and mortality remains unknown.     

A 3-year longitudinal study of sleep disordered breathing in the elderly

Limited and controversial data exist on the natural evolution of sleep disordered breathing (SDB) in untreated individuals. This study examines the evolution of SDB over a 3-yr period in a community-based sample of elderly subjects. From the initial cohort of 854 healthy subjects aged mean±sd 68.4±0.8 yrs, 519 untreated subjects accepted clinical and instrumental follow-up 3.6±1.6 yrs later. SDB was defined as a respiratory disturbance index (RDI) >15 events·h(-1). At baseline, 202 (39%) subjects had an RDI ≤15 events·h(-1) and 317 (61%) had an RDI >15 events·h(-1). 3 yrs later, 280 (54%) subjects were non-SDB and 239 (46%) had SDB. Between evaluations, the RDI decreased from 22.3±16.2 to 16.4±13.0 events·h(-1), with a greater decrease in the number of cases with an RDI >30 events·h(-1) that in those with RDI ≥30 events·h(-1). In the non-SDB group, 81% had a stable RDI and 19% increased their RDI by a mean of 13.7 events·h(-1). In the SDB group, the RDI decreased to values ≤15 events·h(-1) in 36.6% of cases, 63.4% still having SDB. The RDI changes did not depend on weight changes. In healthy elderly subjects, the prevalence and severity of SDB did not show a tendency toward natural worsening, some cases having improvement or a remission independent of weight changes. These findings also suggest that in the elderly, natural SDB progression is still hypothetical.     

Sleep disordered breathing in the elderly

Sleep disordered breathing (SDB), i.e., obstructive, central or mixed sleep apneas, has been recognized as a common occurrence in the elderly. Aging is per se associated with a decrease in the quality of sleep; SDB may further disrupt the sleep architecture in older subjects. The prevalence of obstructive sleep apnea (OSA) increases with aging; available studies report prevalence rates of 11-62%. Furthermore, OSA has been associated with increased mortality in older adults. Central apneas and periodic breathing occur with increased frequency either in subjects with neurological disorders such as infarction, tumor, sequelae of infection, diffuse encephalopathies, or in chronic heart failure. Patients with cerebrovascular disease (stroke, or transient ischemic attacks) have a markedly high prevalence of SDB, mainly OSA. In these patients, SDB is associated with a poorer functional prognosis at 3 and 12 months after the acute event, and a higher mortality. The clinical impact of SDB on cognitive function appears to be modest in patients without dementia, although there is a moderate increase in daytime sleepiness. In Alzheimer's disease (AD) however, SDB occurs more frequently than in non-demented older subjects, and its severity is correlated with the degree of cognitive impairment. The hypothesis of a causal relationship between AD and SDB remains a subject of controversy. The possibility of SDB should be considered in the elderly in the differential diagnosis of "reversible dementias", increased daytime sleepiness, or unexplained right-sided heart failure.     

Habitual loud snoring. A study of prevalence and associations in 850 middle-aged French males

BACKGROUND: Most studies on habitual snoring have focused on its prevalence. However, from the clinical point of view, the intensity of snoring is of upmost importance, as it suggests the existence of sleep apnoeas. OBJECTIVES: The aim of the study was to assess the prevalence of loud snoring using a standard questionnaire and to evaluate the anthropometric and sleep characteristic differences between loud and light snorers in a sample of middle-aged males. METHODS: The subjects were middle-aged active male employees. They completed a structured sleep questionnaire and had standard anthropometric measurements. Subjects reporting habitual snoring (> or =3 nights/week) were further classified as loud or light snorers. RESULTS: Of the 850 male subjects volunteering, 149 (17.5%) were habitual loud snorers. Loud snorers were older and had a greater waist-to-hip ratio as compared with light snorers. In univariate analysis, loud snoring was associated with gasping/snorting during sleep, breathing stops during sleep, waking up too early, excessive daytime sleepiness and falling asleep while watching TV. Logistic regression identified four independent associates of loud snoring: gasping during sleep, excessive daytime sleepiness, falling asleep watching TV and age. CONCLUSIONS: Loud snoring is present in a significant proportion of middle-aged men and is associated with central obesity and age. It disturbs sleep and elicits significant daytime sleepiness. Its association with breathing pauses (univariate) and its independent association with gasping during sleep suggests that loud snoring could be considered a clinical correlate of obstructive sleep apnoeas.     

Obstructive sleep apnoea syndrome is common in subjects with chronic bronchitis. Report from the Obstructive Lung Disease in Northern Sweden studies.

BACKGROUND: In previous studies we have found that subjects with bronchitis have a higher prevalence of 'snoring as a problem' than respiratory healthy subjects. OBJECTIVES: We aimed to study whether the high prevalence of snoring among subjects with bronchitis also represents a high prevalence of obstructive sleep apnoea (OSA). METHOD: Subjects in three age groups born 1919-1920, 1934-1935 and 1949-1950 had been identified as bronchitic in an earlier study (n = 471) and without respiratory symptoms (n = 108). Of the 91 subjects reporting snoring to be a problem, 70 were invited to participate in the study. Sleep investigation was performed in 52 of these 70 subjects. RESULTS: 'Snoring as a problem', predicted OSA to a similar degree in both bronchitic and respiratory healthy subjects. The estimated prevalence for obstructive sleep apnoea with an apnoea/hypopnoea index (AHI) 10 as the cut-off point and concomitant daytime symptoms such as daytime sleepiness or liability to nodding off during breaks in activity in the daytime, was 5.4% for bronchitic subjects and 2.3% for respiratory healthy subjects. Apnoea in addition to snoring predicted OSA better than did snoring alone. Age correlated significantly with AHI, and OSA was most common in the middle-aged group, 61-62 years old. CONCLUSION: OSA is twice as common in subjects with chronic bronchitis as in subjects free of pulmonary disease or symptoms.     

Refractory Insomnia and Sleep-Disordered Breathing: A Pilot Study

Objective: To assess an uncontrolled, open-label trial of sleep-disordered breathing (SDB) treatment on two different samples of chronic insomnia patients. Method: In Study 1 (Retrospective), data from one diagnostic and one continuous positive airway pressure (CPAP) titration polysomnogram were compiled from 19 chronic insomnia patients with SDB. Objective polysomnogram indicators of sleep and arousal activity and self-reported sleep quality were measured. In Study 2 (Prospective), clinical outcomes were assessed after sequential cognitive-behavioral therapy (CBT) and SDB therapy (CPAP, oral appliances, or bilateral turbinectomy) were provided to 17 chronic insomnia patients with SDB. Repeat measures included the Insomnia Severity Index, Functional Outcomes of Sleep Questionnaire, Pittsburgh Sleep Quality Index, and self-reported insomnia indices and CPAP use. Results: In Study 1, seven objective measures of sleep and arousal demonstrated or approached significant improvement during one night of CPAP titration. Sixteen of 19 patients reported improvement in sleep quality. In Study 2, Insomnia Severity Index, Functional Outcomes of Sleep Questionnaire, and Pittsburgh Sleep Quality Index improved markedly with CBT followed by SDB treatment and achieved an average outcome equivalent to curative status. Improvements were large for each treatment phase; however, of 17 patients, only 8 attained a nonclinical level of insomnia after CBT compared with 15 patients after SDB therapy was added. Self-reported insomnia indices also improved markedly, and self-reported SDB therapy compliance was high. Conclusions: In one small sample of chronic insomnia patients with SDB, objective measures of insomnia, arousal, and sleep improved during one night of CPAP titration. In a second small sample, validated measures of insomnia, sleep quality, and sleep impairment demonstrated clinical cures or near-cures after combined CBT and SDB therapies. These pilot results suggest a potential value in researching the pathophysiological relationships between SDB and chronic insomnia, which may be particularly relevant to patients with refractory insomnia.     

Sleep-disordered breathing and quality of life of railway drivers in Greece

BACKGROUND: Sleep-disordered breathing (SDB) and especially obstructive sleep apnea (OSA) are associated with daytime sleepiness and an increased risk for motor vehicle crashes. Previous studies have assessed the prevalence of OSA among professional drivers, but no study so far has focused on railway drivers. The aim of this study was to assess the prevalence of SDB among Greek railway drivers, and correlate it with daytime sleepiness, quality of life, and symptoms. METHODS: The following three different questionnaires were anonymously answered by 226 train drivers: a general questionnaire on their demographics and sleep habits; the Greek version of the Epworth sleepiness scale (ESS); and the Medical Outcomes Study 36-item short form (SF-36). Of the 226 drivers, 50 underwent a sleep study, a physical examination, and an assessment of their respiratory function. RESULTS: Participants were all men, had a mean (+/-SD) age of 46.9+/-3.9 years, were overweight (mean body mass index [BMI], 28.7+/-3.7 kg/m2), and were smokers (59.7%). Snoring was reported by 69.9% of them, and apneas by 11.5%. The mean ESS score was 5.4+/-3.2. SF-36 scores were similar to those of the Greek population. The mean apnea-hypopnea index (AHI) was 11+/-14 events per hour, and the mean pulse oximetric saturation was 93.2+/-2.5%. According to AHI severity, they were divided into the following three groups: group 1, normal breathing function in sleep (n=19; AHI, <5 events per hour); group 2, mild OSA (n=20; AHI, 5.1 to 15 events per hour); group 3, moderate/severe OSA (n=11; AHI, >15 events per hour). The three groups differed in terms of BMI, and neck, waist, and hip circumferences. No difference was detected, though, in ESS and SF-36 scores. CONCLUSION: The majority of the Greek railway drivers are overweight and smokers. The most common reported symptom in the questionnaires is snoring, without significant daytime impairment, while sleep studies show a potentially higher prevalence of OSA. Trial registration: Democritus University of Thrace Identifier: 2979/5-2003. Trial registration: Union of the Greek Railway Drivers Identifier: 536/10-2003.     

承德市区居民睡眠呼吸暂停低通气综合征患病率入户调查

目的 了解承德市区30岁以上居民唾眠呼吸暂停低通气综合征(SAHS)的患病率，为该病的防治提供依据。方法 按照随机整群抽样法，对承德市双桥区部分30岁以上居民进行入户调查，对部分2级及2级以上打鼾进行整夜唾眠呼吸监测。结果 在调查的1168人中打鼾为53．76％，≥2级打鼾为28．25％。≥2级打鼾男性(39．27％)高于女性(17．65％)，统计学上差异有非常显性意义(P＝0．000)。随着年龄增加，打鼾率明显增加。≥2级打鼾在不同职业比较差异均有显性(P＝0．000)，司机组最高(42．00％)。≥2级打鼾中吸烟(41．23％)和饮酒(40．50％)均高于非吸烟(21．36％)和非饮酒(19．73％)。被调查中55．82％认为打鼾不是病，不需要治疗。按唾眠呼吸暂停低通气指数(AHU)≥5次/h为标准，OSAHS患病率为22．64％，按AHI≥5次/h加Epworth嗜唾量表(ESS)评分≥9分为标准判断，人群患病率为4．63％。结论 承德市30岁以上人群中SAHS患病率为4．63％，打鼾及SAHS是严重危害广大人民群众健康的疾病之一，但未引起人们重视．因此需要进一步搞好宣传教育工作。