Periodic limb movements and sleepiness in obstructive sleep apnea patients

BACKGROUND AND PURPOSE: The aim of this study was to assess the possibility that periodic limb movements during sleep (PLMS) could play an additive role in the sleepiness associated with obstructive sleep apnea syndrome (OSAS) before treatment, or could account for residual sleepiness in successfully CPAP-treated patients. PATIENTS AND METHODS: In order to test this hypothesis, we compared objective sleepiness, assessed by the Multiple Sleep Latency Test (MSLT) and subjective sleep propensity, assessed by the Epworth Sleepiness Scale (ESS), in a clinical series of 57 patients consecutively diagnosed with OSAS (apnea/hypopnea index, 53.3+/-26.15), before and after 1 year of treatment with CPAP. RESULTS: Twenty-two patients (38.5%) had significant PLMS (at least 5 PLMS/h of sleep; mean 52.9+/-53.9) in absence of apneas (with CPAP). The two groups (with and without PLMS) were similar in gender distribution, BMI, apnea/hypopnea index or CPAP level. Patients with PLMS were older than those without PLMS. Sleepiness measurements following OSAS diagnosis and after 1 year of CPAP treatment were similar in patients PLMS compared to those without significant PLMS. There was no correlation in the PLMS patient group between the PLM index, Epworth Sleepiness Scale score and mean latency in the MSLT. CONCLUSION: In this study we did not find a link between PLMS and increased objective or self-evaluated sleepiness in OSAS patients, before or after treatment with CPAP.     

Prospective randomized comparison of impedance-controlled auto-continuous positive airway pressure (APAP(FOT)) with constant CPAP

Background: The measurement of impedance permits reliable detection of obstructive apneas, hypopneas and upper airways resistance syndrome.Objective: To establish whether impedance-controlled self-adjusting positive airway pressure therapy (APAP(FOT)) is equally as good as constant continuous positive airway pressure (CPAP) in the treatment of sleep apnea syndrome (OSAS).Methods: Twenty men and five women with OSAS (age 52.8+/-9.0 years, body mass index (BMI) 31.4+/-5.0 kg/m(2), AHI 32.2+/-18.1/h (mean+/-SD)) underwent baseline polysomnography, manual CPAP titration and two nights of treatment, one with APAP(FOT), one with constant CPAP.Results: With both modes, a significant reduction in respiratory disturbances was seen (apnea/hypopnea index (AHI) baseline 32.2+/-18.1/h, constant CPAP 6.6+/-8.7, APAP(FOT) 5.5+/-3.8/h, P<0.001 baseline vs. each treatment mode). Under APAP(FOT), the sleep profile was normalized (S3/4 baseline 16.3+/-13.9% total sleep time (TST), APAP(FOT) 21.6+/-10.9% TST, P<0.05, rapid eye movement (REM) 14.2+/-6.7% TST vs. 20.3+/-7.3% TST, P<0.01), while with constant CPAP, a tendency towards improvement was found. The mean treatment pressure with APAP(FOT) was significantly lower than the constant CPAP (5.7+/-2.1 vs. 8.3+/-1.6 mbar, P<0.001).Conclusion: We conclude that APAP(FOT) is at least as effective as constant CPAP in normalizing sleep and breathing in OSAS.     

Erectile dysfunction, obstructive sleep apnea syndrome and nasal CPAP treatment

BACKGROUND AND PURPOSE: To evaluate the effect of one month of continuous positive airway pressure (CPAP) in a subgroup of obstructive sleep apnea (OSA) patients with erectile dysfunction (ED) and compare this subgroup with age- and body mass index (BMI)-matched OSA patients without ED. PATIENTS AND METHODS: Prospective general, sleep, psychiatric and sexologic evaluations were conducted. Epworth Sleepiness Scale (ESS), Beck Depression Inventory (BDI), Sleep Disorders Questionnaire (SDQ), Quality of Life SF-36, and polysomnography were used. Seventeen OSA patients with ED were compared prior to CPAP treatment and during CPAP treatment with age- and BMI-matched OSA patients without ED. Parametric and non-parametric statistics, chi-square, Fisher exact test and multiple regression analyses were performed. RESULTS: Ninety-eight men (BMI=28.8 kg/m2, apnea-hypopnea index (AHI)=49.6 events/h, ESS=14.8, BDI=8.4, and lowest SaO2=75.3%) were divided into subgroups of lowest SaO2>80% (A) and lowest SaO2< or =80% (B). (A) Forty-six men had a mean lowest SaO2 of 85.7%+/-2.9, AHI=29.5+/-17.6, age=46.3+/-9.3 years, ESS=13.6+/-4.2, BMI=25.8+/-4.8. Seven of the patients had ED. (B) Fifty-two men had a mean lowest SaO2=60.10+/-10.0%, AHI=67.4+/-24.5, BDI=9.0+/-6.9, age=47.4+/-9.4 years, ESS=16.2+/-4.4, BMI=31.4+/-5.1. Twenty-one of the patients had ED (chi2: P=0.006). Significant variables for ED were lowest SaO2 and age (r=0.17). CPAP-treated subgroup: ED subjects had significantly lower SaO2, ESS, BDI and SF-36 subscale scores than OSA controls. Nasal CPAP eliminated the differences between groups, and ED was resolved in 13 out of 17 cases. CONCLUSIONS: ED in OSAS is related to nocturnal hypoxemia, and about 75% of OSAS patients with ED treated with nasal CPAP showed remission at one-month follow-up, resulting in significant improvement in quality of life.     

Gender differences on polysomnographic findings in Greek subjects with obstructive sleep apnea syndrome

BACKGROUND AND PURPOSE: Studies from North American clinics have reported that females with obstructive sleep apnea syndrome (OSAS) are about the same age as males but are heavier, have less severe apnea and make up a much smaller proportion of cases. We examined polysomnographic differences between Greek men and women with OSAS in order to study the influence of gender on clinical presentation and laboratory findings. PATIENTS AND METHODS: This retrospective study included a cohort of 1,010 Greek patients (844 males, 166 females) diagnosed with OSAS by overnight polysomnography (PSG), who were referred to the Sleep Disorders Center of Evangelismos Hospital, Athens Medical School, University of Athens. All patients were studied over a period of three consecutive years, during which time clinical and polysomnography (PSG) findings were compared. RESULTS: Body mass index (BMI) was similar in men and women with OSAS (BMI=31.6+/-5.5kg/m(2) in men versus BMI=32.5+/-8.1 (SD) kg/m(2) in women). Female patients were significantly older than male patients (56.9+/-10.6 versus 50.6+/-11.7 year, P=0.001). The mean apnea-hypopnea index (AHI) during total sleep time was higher in men than in women (42.4+/-28.2 versus 33.2+/-27.7 events/h, P<0.001). The AHI in non-rapid eye movement (NREM) sleep was higher in men than in women (42.9+/-28.9 versus 32.6+/-28.7 events/h, P<0.001), but in rapid eye movement (REM) sleep AHI was similar in men and women (36.0+/-23.3 versus 34.9+/-25.4 events/h). Forty percent of men had AHI-REM sleep >AHI-NREM compared to 62% of women, and the difference between REM and NREM-AHI was significantly less in men than in women (14.21+/-11.18 versus 19.76+/-13.43 events/h, P<0.001)). Several aspects of sleep were worse in women versus men: sleep efficiency index was lower (79.4+/-16.1% versus 85.1+/-12.5%, P<0.001); sleep onset latency (27.7+/-27.7 versus 17.9+/-18.1min, P<0.001), and REM onset latency (161.5+/-76.2 versus 145.7+/-71.4min, P<0.018) were longer; wake time after sleep onset (WASO) was also greater in women (42.6+/-46.5 versus 30.7+/-34.9min, P<0.003). CONCLUSIONS: In Greek subjects with OSAS, there was no difference in BMI, and female patients were significantly older than male patients. OSAS was diagnosed in men five times more often than in women. AHI was greater in men than in women, but women are more likely than men to have a higher AHI in REM than NREM. Sleep quality is worse in female than in male patients.     

持续气道正压通气治疗癫(痫)与阻塞性睡眠呼吸暂停综合征共病疗效的系统评价

目的 评价持续气道正压通气治疗癫(痫)与阻塞性睡眠呼吸暂停综合征共病的有效性.方法 以sleep apnoea、obstructive sleep apnoea、OSA、obstructive sleep apnoea syndrome、OSAS、sleepapnoea syndromes、sleep-related breathing disorder、epilepsy、continuous positive airway pressure、CPAP等英文词汇计算机检索1980年1月1日-2017年2月28日美国国立医学图书馆生物医学信息检索系统(PubMed)、荷兰医学文摘(EMBASE/SCOPUS)、Cochrane图书馆等数据库收录的关于持续气道正压通气治疗癫痼与阻塞性睡眠呼吸暂停综合征共病的随机对照临床试验、临床指南、系统评价(包括Meta分析)、病例对照研究、回顾性队列研究等.采用Jadad量表、Cochrane系统评价手册和RevMan 5.3统计软件进行文献质量评价和Meta分析.结果 共获得1197篇英文文献,经剔除重复和不符合纳入标准者,最终纳入17篇文献,包括临床指南1篇、系统评价和Meta分析各1篇、随机对照临床试验l篇、病例对照研究10篇、回顾性队列研究3篇.结果显示:(1)持续气道正压通气可以减少癫(痫)与阻塞性睡眠呼吸暂停综合征共病患者癫(痫)发作频率甚至无发作.(2)持续气道正压通气可以减少难治性癫(痫)与阻塞性睡眠呼吸暂停综合征共病患者癫(痫)发作频率.(3)持续气道正压通气可以减少老年癫(痫)与阻塞性睡眠呼吸暂停综合征共病患者癫(痫)发作频率.(4)对3项Jadad评分≥4分的临床研究共153例癫(痫)与阻塞性睡眠呼吸暂停综合征共病患者进行Meta分析,与未接受持续气道正压通气组相比,接受持续气道正压通气组癫(痫)发作频率减少＞50％的病例数增加(RR=3.170,95％ CI:1.650 ～ 6.090;P=0.001).结论 持续气道正压通气可以减少癫(痫)与阻塞性睡眠呼吸暂停综合征共病患者癫(痫)发作频率,其治疗效果取决于患者依从性,突然停止或压力不足可能导致癫痫发作频率增加,这一结论尚待更多随机对照临床试验证实.     

A pilot study evaluating acute use of eszopiclone in patients with mild to moderate obstructive sleep apnea syndrome

OBJECTIVE: To evaluate the effects of eszopiclone on measures of respiration and sleep using polysomnography in patients with mild to moderate obstructive sleep apnea syndrome (OSAS). METHODS: This double-blind, randomized crossover study included patients (35-64 years) with mild-to-moderate OSAS [apnea and hypopnea index (AHI) range 10 and 40]. Patients received either eszopiclone 3mg or placebo for two consecutive nights, with a 5-7 day washout between treatments. Continuous positive airway pressure (CPAP) was not allowed on nights in the sleep laboratory. RESULTS: The primary endpoint, mean total AHI, was not significantly different from placebo (16.5 with placebo and 16.7 with eszopiclone; 90% confidence interval (CI) -1.7, 1.9). No significant differences in total arousals, respiratory arousals, duration of apnea and hypopnea episodes, or oxygen saturation were noted. Significant differences in spontaneous arousals (13.6 versus 11.4 for placebo and eszopiclone, respectively; 90% CI -3.7, -0.7), sleep efficiency (85.1% and 88.4%; p=0.0075), wake time after sleep onset (61.8 and 48.1 min; p=0.0125), and wake time during sleep (55.9 and 43.2 min; p=0.013) were noted after eszopiclone treatment. Eszopiclone was well tolerated. CONCLUSIONS: In this pilot study, eszopiclone did not worsen AHI, and it improved sleep maintenance and efficiency. Further study is warranted to determine whether eszopiclone could improve CPAP compliance or next-day function in patients with OSAS.     

Influence of nocturnal hypoxemia on the function of the visual tract in the course of the obstructive sleep apnea syndrome

BACKGROUND AND PURPOSE: In patients with obstructive sleep apnea (OSA) syndrome the episodes of upper airway obstruction lead to hypoxemia during sleep. The aim of the study was to establish the influence of sleep hypoxemia on the function of the visual tract in OSA patients. MATERIAL AND METHODS: The latency and amplitude of wave P100 of visual evoked potentials have been studied in 35 patients with OSA syndrome (mean apnea index 48+/-19). The diagnosis of OSA was established on the basis of continuous recordings of the respiratory function during sleep with additional full polysomnography in 17 patients. RESULTS: Mean absolute latency of P100 was longer in OSA patients than in healthy controls (117.0+/-8.8 ms vs. 104.3+/-4.6 ms, p<0.001). The differences in the amplitude of P100 were not significant (5.9+/-2.6 mV in OSA patients and 7.62+/-3.04 mV in healthy persons). In 60% of patients the latency of P100 exceeded 118 ms; in this group of patients the mean SaO2 during sleep apneas was lower than in patients with normal P100 latency (46+/-15% vs. 69+/-10%, p<0.05). Full polysomnographic studies revealed that in patients with prolonged latencies as compared with patients with normal P100 latencies there were lower: minimal SaO2 during NREM sleep (63+/-12% vs. 78+/-8%, p<0.05), as well as mean and minimal SaO2 during REM sleep (53+/-15% vs. 80+/-5% and 46+/-15% vs. 69+/-10%, p<0.05), without differences in apnea index or apnea duration. CONCLUSIONS: In patients with OSA syndrome the electrophysiological abnormalities suggesting damage of the optical tract may develop probably as a consequence of profound sleep hypoxemia.     

Predictors of symptoms of anxiety and depression in obstructive sleep apnea

BACKGROUND AND PURPOSE: To assess factors associated with anxiety and depression in patients with obstructive sleep apnea syndrome (OSAS). PATIENTS AND METHODS: The study was comprised of a postal survey with a hospital chart review. Questionnaires were mailed to 242 previously hospitalised patients with OSAS. We assessed anxiety and depression with the Hospital Anxiety and Depression scale (HAD). Scores on the two HAD scales (0-21 scale, higher scores represent poor health) were categorized as normal/borderline (< or =10), and corresponding to a clinical diagnosis of anxiety or depression (> or =11). In logistic regression analysis, we assessed the association with HAD scores > or =11, using variables from the chart review and self-reported data on demographics, disease history, smoking status, CPAP/BiPAP use, and daytime sleepiness as assessed with the Epworth Sleepiness Scale (ESS), as potential predictors. RESULTS: One hundred and seventy-eight patients (74%) with mean (SD) age 55 (11) years and body mass index (BMI) of 31 (5) kgm(-2) responded to the questionnaire. In multivariate logistic regression analysis, only low compliance with CPAP therapy (odds ratio (OR) 5.60, P=0.005) predicted high level of anxiety, and low compliance with CPAP therapy (OR 3.59, P=0.03) and daytime sleepiness (OR 1.14 per unit increase in ESS score, P=0.02) were the only predictors of high level of depression. CONCLUSIONS: High anxiety score was associated with non-compliance with CPAP therapy. High depression score was associated with daytime sleepiness and non-compliance with CPAP therapy.     

Evening and morning blood gases in patients with obstructive sleep apnea

BACKGROUND AND PURPOSE: The purpose of this study was to see if blood oxygen levels deteriorate overnight during obstructive sleep apnea (OSA). Before and after sleep, arterial blood gases (ABGs) in OSA subjects and controls were drawn during a diagnostic night, as well as during a continuous positive airway pressure (CPAP) night for the OSA subjects. PATIENTS AND METHODS: Subjects, both male and female, were referred to our sleep laboratory for symptoms of daytime somnolence. Subjects consisted of a control group (N=13) with a mean apnea hypopnea index (AHI) of 3.3 events/h and a study group (N=22) with a mean baseline AHI of 57 events/h. RESULTS: With the subject supine, resting room air ABGs were drawn at 'lights out' on the evening before (PM) nocturnal polysomnography and in the morning (AM) at discontinuation ('lights on') of the sleep study. In controls, PM PaO(2) (79.4+/-9.7 mmHg) was not significantly different from AM PaO(2) (80.2+/-8.9 mmHg, P=0.5). In apneic subjects, the PM PaO(2) was 78.7+/-7.2 mmHg compared to an AM PaO(2) of 72.6+/-8.3 mmHg (P<0.05). The AM PaO(2) after a night of CPAP treatment in the OSA subjects was 77.5+/-10.2 mmHg compared to the PM PaO(2) of 76.0+/-6.0 mmHg (NS). The PM and AM PaCO(2)s were not different in controls or in study subjects under baseline conditions. However, during titration with nasal CPAP, the PaCO(2) was significantly higher in the morning after CPAP treatment [43.1+/-4.8 vs. 46.1+/-4.8 mmHg, respectively (P<0.05)]. CONCLUSIONS: OSA subjects showed a fall in overnight resting oxygenation. This could be accounted for by overnight deterioration of gas exchange and is ameliorated by CPAP.     

Improvement of subjective work performance among obstructive sleep apnea patients after treatment with continuous positive airway pressure

Obstructive sleep apnea syndrome (OSAS) is a significant problem for some patients presenting with snoring and excessive daytime sleepiness. The 'golden standard' therapy in OSAS is considered to be nasal continuous positive airway pressure (CPAP). The effects of CPAP on work performance in sleep apnoics has not been studied previously. One hundred and fifty-two patients with OSAS participated in an open label study. The patients were diagnosed as suffering from severe OSAS after they underwent overnight polysomnography showing that their apnea indexes were at least 20. The participants answered four questions concerning self-perceived work performance prior to and after using CPAP during 6 months. There were highly statistically significant decreases (P < 0.000001) in work performance difficulties as graded by the patient. The results of this study indicate that CPAP treatment improves subjective work performance in patients suffering from OSAS.     

Erythrocyte deformability, plasma viscosity and oxidative status in patients with severe obstructive sleep apnea syndrome

BACKGROUND AND PURPOSE: In patients with severe obstructive sleep apnea syndrome (OSAS), diurnal changes of plasma viscosity and erythrocyte deformability were measured to elucidate the possible mechanism of cardiovascular diseases in OSAS patients. PATIENTS AND METHODS: Plasma viscosity and erythrocyte deformability was determined in 11 OSAS patients and 11 healthy subjects matched by sex and age. Plasma viscosity was measured by a cone-plate viscometer, and erythrocyte deformability was determined by filtration technique. Whole blood counts were performed and oxidative status of the patients' plasma and erythrocytes were evaluated. RESULTS: OSAS patients had higher plasma viscosity than controls, both in the morning (1.74+/-0.3 vs. 1.36+/-0.2 mPas, P<0.002) and evening (1.55+/-0.2 vs. 1.27+/-0.1 mPas, P<0.002), and morning plasma viscosity was significantly higher than the evening level (P<0.05). Morning plasma viscosity of patients was inversely correlated with their mean nocturnal SaO(2). Morning plasma malonyldialdehyde level was significantly higher in the patients than in the controls (69.7+/-30.5 vs. 45.5+/-11.0 nmol/l, P<0.005). Erythrocyte deformability of the patients was slightly lower. CONCLUSIONS: We have observed that plasma viscosity is high both in the morning and in the evening in severe OSAS patients. This elevation may predispose OSAS patients to myocardial infarction and stroke by increasing blood viscosity. Low nocturnal mean SaO(2) may be responsible for the high plasma viscosity in these patients.     

A cognitive-behavioral weight reduction program in the treatment of obstructive sleep apnea syndrome with or without initial nasal CPAP: a randomized study

BACKGROUND AND PURPOSE: To evaluate (a) whether an active weight reduction strategy based on the cognitive-behavioral approach and an initial very-low-calorie diet might lead to short- and long-term weight loss and alleviation of OSAS; and (b) whether the results of this intervention could be enhanced by combining it with nasal continuous positive airway pressure (CPAP) treatment during the first 6 months. PATIENTS AND METHODS: Thirty-one obese male symptomatic sleep apnea patients underwent a 2-year weight reduction program with total follow-up of 36 months from baseline. The mean age (+/-SD) was 49.1+/-7.9 years, body mass index 43.8+/-5.4, and oxygen desaturation index (ODI4) 51.3+/-31.1. The patients were randomized to CPAP (17 patients) and non-CPAP groups (14 patients). RESULTS: The mean weight loss was 19.1+/-10.2 kg (14% of the original weight) for the whole group at 6 months, 18.3+/-13.2 (13%) at 12 months and 12.6+/-14.7 kg (9%) at 24 months. Excellent or good treatment results, as defined in terms of an ODI4 (average number of oxygen desaturation events p/h>4% from baseline) reduction of at least 50% from the baseline, were seen in 61% of patients at 6 months and were still observable in 42% of patients at 24 months. The correlations between changes in weight and in ODI4 were 0.59 (P<0.01) at 6 months, 0.68 (P<0.01) and 0.75 (P<0.01) at 24 months. Adding CPAP treatment to the weight reduction therapy for the first 6 months did not result in greater weight loss or diminution of desaturation indices (without CPAP) at any time point. One year after the termination of the program the mean weight loss was 6.6+/-12.9 kg, and 42% of patients still showed at least 5% weight loss as compared with their original weight. CONCLUSION: Satisfactory weight loss associated with improvement of OSAS could be achieved by means of a cognitive-behavioral weight loss program. Adding CPAP in the initial phase of the weight reduction program did not result in significantly greater weight loss.     

Oxygen administration improves the serum level of nitric oxide metabolites in patients with obstructive sleep apnea syndrome

OBJECTIVES AND BACKGROUND: Nocturnal apnea and hypoxia are implicated in the pathogenesis of pulmonary and systemic hypertension in obstructive sleep apnea syndrome (OSAS). We have hypothesized that vasodilating factors including nitric oxide (NO) are affected by nocturnal apnea and hypoxia in patients with OSAS. METHOD: We examined the serum level of NO production in 24 patients with OSAS (mean age 54.2+/-7.9 years) and 24 age-matched control subjects (53.4+/-8.1 years) and tested the effects of oxygen administration on the production of NO in the patients. RESULTS: The serum level of nitrite/nitrates (NO(x)), which are stable metabolites of NO, was lower in patients with OSAS than in control subjects. Administration of 1-2 l/min of oxygen during night increased the patients' NO(x) level from 35.6+/-7.3 to 57.8+/-11.6 microM. Compressed air administration did not affect the NO(x) level in the patients. CONCLUSION: These results indicate that systemic NO production is impaired in OSAS patients, possibly due to nocturnal hypoxia.     

Mandibular advancement device in Parkinson's disease: a pilot study on efficacy and usability

Background/objectivesContinuous positive airway pressure (CPAP) is efficacious in the treatment of obstructive sleep apnea syndrome (OSAS) in patients with Parkinson's disease (PD). However, this treatment is often not well tolerated in this disabled population. We explored, in a pilot study, the efficacy, observance, and usability of mandibular advancement device (MAD) for the treatment of OSAS in this peculiar population.Patients/methodsTwenty patients with PD and moderate or severe OSAS were included in the study. Ten patients had refused or not tolerated the validated treatment with CPAP so that they were treated with MAD. The patients treated with MAD were matched for sex, age and body mass index (BMI) to 10 patients with PD treated with CPAP.We explored the efficacy of MAD on sleep disorders complaints (PDSS-2) and on sleep recordings. We compared adherence, tolerance and usability with MAD and with CPAP.ResultsMAD improved sleep complaints increasing PDSS-2 scores (85 [55–106] vs 106 [88–126], p < 0.005), and sleep respiratory measures reducing apnea/hypopnea index (AHI) (50.8 [30.0–76.4] vs 9.4 [5.0–45.2], <0.001) and oxygen desaturation index (22.9 [2.1–92.0] vs 3.8 [0.2–34.2], p < 0.05). Observance was higher with MAD than with CPAP. Usability and caregiver satisfaction were higher with MAD than with CPAP whereas side effects were similarly reported.ConclusionMandibular advancement device may be an noteworthy alternative treatment of OSAS in patients with PD.     

Examining the construct of depression in obstructive sleep apnea syndrome

BACKGROUND AND PURPOSE: Depression is commonly reported by patients suffering from Obstructive Sleep Apnea Hypopnea Syndrome (OSAS). We used the factor structure of the Beck Depression Inventory-2nd edition (BDI-II) to examine the unique contributions of OSAS severity and obesity to depressive symptoms in OSAS. We predicted that the Somatic and Cognitive dimensions of the BDI-II would be more strongly associated with apnea severity and obesity, respectively. PATIENTS AND METHODS: Ninety-three moderate to severe OSAS patients (61 men, 32 women) were seen for psychological testing prior to initiating CPAP treatment. They completed the BDI-II and Epworth Sleepiness Scale (ESS). Measures of apnea severity (RDI, percent of sleep time below 90% oxygen saturation) and BMI were also collected. RESULTS: RDI was significantly related to BMI and BDI-II total score, but not to ESS score. BMI was related to BDI-II total score and ESS score. Partial correlations indicated that RDI was independently related to the Somatic dimension on the BDI-II. By contrast, BMI was uniquely associated with the Cognitive dimension. Although there was no difference in depression scores between men and women, the relationship between the Somatic factor and apnea severity was significant in men, whereas obesity and the Cognitive factor were significantly associated in women. CONCLUSIONS: OSAS severity and obesity contribute differentially to symptoms of depression in OSAS. In addition, symptoms of depression in OSAS manifest differently in men than in women.     

Prevalence of central sleep apnea during continous positive airway pressure (CPAP) titration in subjects with obstructive sleep apnea syndrome at an altitude of 2640 m

BackgroundThe occurrence of central apneas when applying positive pressure (CPAP) to patients with obstructive sleep apnea syndrome (OSAS) is called complex sleep apnea (CompSA). This causes poor adherence to CPAP and persistence of symptoms. In Bogota, a city located at an altitude of 2640 m above sea level, chronic hypoxemia can generate certain instability of the respiratory system during sleep which could increase the presence of central apnea. The aim was to establish the prevalence of central apnea (central apnea index >5/h) in adults with moderate or severe OSAS during CPAP titration, and the factors associated with this.MethodPatients over 18 years old with OSAS were referred to the Fundacion Neumologica Colombiana Sleep Center, from January 2008 to June 2010. Polysomnogram (PSG) for CPAP titration was performed according to the American Academy of Sleep Medicine criteria. The prevalence was calculated and the clinical and baseline PSG factors associated with the CompSA were analyzed.ResultsWe included 988 patients, 58% men. CompSA prevalence was 11.6%. Factors associated with CompSA were: central apneas in the baseline PSG (OR: 5.34 [3.49–8.16]), history of heart failure (OR: 2.53 [1.58–4.07]), and male sex (OR: 1.68 [1.06–2.69]).ConclusionThe prevalence of complex sleep apnea in Bogota (11.6%) was intermediate compared to the reported in lower altitudes. The factors associated with the development of CompSA were male sex, heart failure, and the presence of central apnea in the baseline PSG.     

Dose-response relationship between CPAP compliance and measures of sleep apnea severity

BACKGROUND: Obstructive sleep apnea is a prevalent condition with serious medical and psychosocial consequences. Nasal continuous positive airway pressure (CPAP) is the treatment of choice and has been shown to reduce the frequency of nocturnal respiratory events, improve sleep architecture, and decrease daytime sleepiness. However, little is known about the dose-response relationship between CPAP compliance and measures of sleep apnea severity. This study examined the relationship between level of CPAP compliance and change in polysomnographic measures of sleep apnea severity. METHODS: Twenty-three CPAP-naive OSA patients were studied. None had other major medical illnesses or were receiving antihypertensive medication. Sleep apnea variables were measured at baseline and after 1 week of treatment. Objective CPAP compliance was measured nightly and was defined as the average number of hours of use per night. RESULTS: Higher rates of CPAP compliance were linearly associated with significant reductions in the respiratory disturbance index (R=0.49, P=0.017), the oxygen desaturation index (R=0.48, P=0.029), and the arousal index (R=0.51, P=0.016). CONCLUSIONS: These data suggest that increased CPAP compliance is linearly associated with reductions in sleep apnea severity such that greater reductions in apnea were seen with increased CPAP use. It should be noted that all patients were reasonably compliant (i.e. >4h CPAP use/night) and that even within this range of reasonable compliance, there was a significant benefit with more as opposed to less compliance. These findings offer support to the current recommendation that CPAP be used during the total time in bed to optimize treatment of polysomnographic measures of sleep apnea.     

Headache characteristics in obstructive sleep apnea syndrome and insomnia

OBJECTIVES: To determine headache characteristics in the obstructive sleep apnea syndrome (OSAS) and in insomnia. PATIENTS AND METHODS: Fifty-six OSAS patients and 50 insomnia patients were assessed in the same time period. Patients in both groups underwent an accurate interview to investigate headache occurrence and its characteristics. Results - Headache was reported by 49% of OSAS patients and 48% of insomnia patients. In OSAS patients headache had most frequently a tension-type pattern. Headache occurred on awakening in 74% of OSAS patients, more frequently than in insomnia patients (40%) (chi(2); P < 0.04). The occurrence of morning headache appears to be significantly correlated with nocturnal oxygen desaturation and OSAS severity. CONCLUSION: Headache is a common finding in both OSAS and insomnia patients. Because morning headache seems to be more specific for OSAS than insomnia, and in OSAS its occurrence seems to be associated with disease severity, we hypothesize the involvement of certain pathogenic mechanisms associated with OSAS.     

Nocturnal cardiac arrhythmia in patients with obstructive sleep apnea

BACKGROUND AND PURPOSE: Nocturnal cardiac arrhythmias occur in patients with obstructive sleep apnea (OSA), reportedly as a consequence of the autonomic effects of recurrent apnea with subsequent oxygen desaturation. We have investigated whether different patterns of OSA are associated with specific arrhythmia during sleep. PATIENTS AND METHODS: Electrocardiographic (ECG) data recorded during polysomnography (PSG) were analysed in 257 consecutive OSA patients to determine the prevalence of cardiac rhythm disturbances, and to relate these to breathing pattern (normal, apnea/hypopnea, recovering ventilation, snoring) and oxygen saturation. RESULTS: Arrhythmias were found in 18.5% of patients. Patients with nocturnal bradyarrhythmia (BA) had higher values of ventilatory disturbance (apnea-hypopnea index [AHI] 58.8+/-36.8 vs 37.2+/-30.3, p=0.02), mean desaturation amplitude (8.9+/-4 vs 5.9+/-3.4%, p=0.03), and a lower SaO(2) nadir (69% vs 77%, p=0.003) than those without arrhythmia. The prevalence of BA in patients with AHI>or=30/h was significantly higher than that observed in those with AHI<30/h (7.8% vs 1.5%, respectively; chi(2)=5.61, p=0.01). In contrast, patients with tachyarrhythmia (TA) had no significant differences in AHI, mean desaturation amplitude or SaO(2) nadir than those without arrhythmia. No associations were found between arrhythmia and the presence of comorbidity or concomitant medical therapy, except for an association between tachyarrhythmia and chronic obstructive pulmonary disease (COPD) (odds ratio 2.53; 95% confidence intervals 1.1-5.8, p=0.03). CONCLUSIONS: We conclude that while BA during sleep is associated with OSA severity, concomitant COPD or beta(2)-treatment may play a role in the development of TA during sleep.     

S100B and NSE serum levels in obstructive sleep apnea syndrome

BACKGROUND AND PURPOSE: Obstructive sleep apnea syndrome (OSAS) is a chronic disease ranging from innocuous to life-threatening and causes brain alterations manifested by neuropsychiatric symptoms. Neuron-specific enolase (NSE) and the astrocytic protein S100B are established sensitive peripheral biochemical markers of brain injury. In the present work we measured the serum levels of S100B and NSE in order to evaluate the deleterious effects of OSAS to the brain. PATIENTS AND METHODS: We studied 29 male patients with OSAS and 17 male asymptomatic control subjects with an apnea-hypopnea index (AHI) less than five events per hour. Patients and control subjects were evaluated by full-night polysomnography (PSG) and by Mini International Neuropsychiatric Interview (MINI) for the presence of neuropsychiatric symptoms. In the morning following the PSG, blood was collected and serum levels of S100B and NSE were measured using standard techniques. RESULTS: The AHI in the OSAS group was (mean+/-SD) 27+/-25 AH/h, ranging from 5 to 99 AH/h. S100B was higher in OSAS (0.15+/-0.09 microg/l) than in the control group (0.08+/-0.06 microg/l; P<0.01). Serum NSE was similar in both groups (17.5+/-12.2 vs. 15.8+/-6.8ng/ml). CONCLUSIONS: We report elevated serum S100B levels in OSAS patients in this study.