Obstructive sleep apnoea

ABSTRACT— An epidemiological survey of the prevalence of snoring and sleep apnoeas was performed on 3479 30-69-year-old men living in Bologna, north-east Italy. First a postal questionnaire was sent. It was returned with appropriate answers by 1170. A 20% random sample of those who did not answer were invited by telephone to return the questionnaire. Among these groups 119 (10%) and 19 (5.6%) respectively answered that they always snored. A random sample of 40 every-night snorers were studied by polysomnography. Based on the frequency of every-night snoring and the results of polysomnography we estimated that the minimal prevalence of sleep apnoea among 30-69-year-old men was 2.7% considering an apnoea + hypopnoea index of 10 or more pathological. According to the Lugaresi classification we had a 2.5% prevalence of heavy snorers’ disease (HSD) Stage 1 or higher. These figures indicate that obstructive sleep apnoea during sleep is a major public health problem.

Introduction: The research hypothesis under test was that functional orthopaedic treatment with the Twin-block appliance
increases the oropharyngeal airway as well as correcting the jaw relationships in class II division 1 patients.
Method: 20 cases, 10 male, 10 female. Age range: 11-18 years, average treatment time 9.4 months were randomly selected
from the records of a previously completed prospective trial. Cephalometric radiographs taken before and after treatment
were analysed. p, the shortest distance between the soft palate and posterior pharyngeal wall and t, the shortest distance
between the tongue and the posterior pharyngeal wall were measured.
Results: There was a statistically significant increase in both p and t after Twin-block appliance treatment (p=0.000). A
control group selected from normative data matched individually for age and sex and treatment time showed no change
over the same growth period.
Conclusions: In Class II division 1 malocclusion, the oropharyngeal airway is already reduced compared to Class I and
Class II. Treatment involving premolar extraction and incisor retraction further reduces the airway as does headgear and is
contraindicated. Functional appliance treatment is the method of choice as it enlarges the oropharyngeal airway reducing
the potential for obstructive sleep apnoea.

There is as yet no convincing evidence that acetazolamide, a carbonic anhydrase inhibitor, is effective in obstructive sleep apnoea. A study was therefore designed to examine the effect of acetazolamide (250 mg/day) on sleep events and ventilatory control during wakefulness in nine patients with the sleep apnoea syndrome. In eight of the nine patients the apnoea index and the total duration of apnoea were reduced by acetazolamide, and the mean (SEM) apnoea index of all patients changed from 25.0 (6.7) to 18.1 (5.8) episodes an hour. Furthermore, the total time of arterial oxygen desaturation (SaO2)--more than 4% depression in SaO2 from the baseline sleeping level--divided by total sleep time was also significantly decreased and its mean (SEM) value improved from 24.1 (7.9) to 13.6 (4.8)% of total sleep time. Five of the seven patients with varying degrees of daytime hypersomnolence had their symptoms obviously improved. There was no patient whose predominant type of apnoea was conve...

There is a background relationship between the mode of breathing and antero-posterior jaw relation. Severe mandibular deficiency has been linked to reduced oropharyngeal airway dimension. Dental literature reported many studies on functional appliances and their effects, but there are few published studies on their effects on the airway.
Objectives: To investigate the immediate effect of the Twin block (TB) functional appliance on the airway in patients with class II division1 malocclusion on skeletal II base and to measure the immediate changes in the position of the hyoid bone after insertion of the TB appliance.
Materials and Methods: Two lateral cephalometric radiographs were taken and analyzed one before and one after insertion of the TB appliance for the 19 patients. The age range 10-14 years. Immediate change in the airway was performed by measuring the changes in the vertical position of the hyoid bone relative to the mandibular plane (H1) and to the (cv3-RGN) plane (H2). The change in the airway can be measured by the change in the vertical position of the hyoid bone before and after insertion of TB appliance (H-H1) + (H-H2).
Results: The hyoid bone changes in a more superior position after the insertion of the TB appliance. The mean change was 11.8mm, with SD 2.8mm (P = 0.0001) at 0.01% level.
Conclusion: Vertical hyoid bone position was changed in a more superior position immediately after the insertion of the TB appliance on patients with class II division 1 malocclusion on skeletal II base. Further, the TB has an immediate positive effect in the airway.

Obstructive sleep apnea (OSA) can present with or provoke various psychological symptoms. In this article, we critically review studies that have examined dreams, dream recall, and dream content in patients with OSA. Obstructive events induce recurrent sleep fragmentation and intermittent desaturations in patients with OSA, which may trigger different parasomnias, including nightmares. Contradictory results have been reported concerning dreams in patients with OSA; while some investigators have reported less dreams in OSA patients, others have described that patients with OSA have increased dreams with emotional content, mainly violent and hostile content. Although there are reports of respiratory-related dream content in patients with OSA, most studies that have assessed the dream content of patients with OSA revealed that respiratory-related dream content was unusual. A clear association between post-traumatic stress disorders, comorbid OSA, and nightmares has been reported in several studies. Furthermore, an improvement in nightmare frequency with continuous positive airway pressure (CPAP) treatment has been shown. An inverse relationship between the severity of OSA reflected by the apnea-hypopnea index and dream recall has been demonstrated in several studies. Future studies should differentiate between patients with non-stage specific OSA and patients with rapid eye movement (REM) predominant OSA.

Obstructive sleep apnoea (OSA) might cause right ventricular dysfunction and pulmonary hypertension. We aimed to determine the effects of nasal continuous positive airway pressure (CPAP) therapy on right ventricular myocardial performance index (MPI) in OSA patients without hypertension. 49 subjects without hypertension, diabetes mellitus, any cardiac and pulmonary disease had overnight polysomnography and echocardiography. In 18 moderate-severe OSA (apnea-hypopnea index > or = 15) patients, right ventricular free wall diameter (RVFWD) was measured by M-mode, and right ventricular MPI was calculated as (isovolumic contraction time+ isovolumic relaxation time) / pulmonary ejection time using Doppler at baseline and after 6 months CPAP therapy. Mean age was 46.5 +/- 4.9 year. Patients had high body mass index (BMI: 30.6 +/- 4,0 kg/m2), but there was no change in either BMI or blood pressures after 6 months. Right ventricular end-diastolic and end-systolic diameters were in normal l...

The short, repetitive hypoxaemic episodes observed in obstructive sleep apnoea (OSA) may determine small augmentations in mature red blood cells. It is unknown whether they affect reticulocyte release. This study explored whether the number and degree of maturation of circulating reticulocytes may be altered in OSA, possibly through the effect of erythropoietin. Fifty male adult patients with suspected OSA, normoxic during wakefulness, were studied. After nocturnal polysomnography, a blood sample was withdrawn for blood cells count, erythropoietin, iron and transferrin determination. Reticulocyte concentration and degree of immaturity [high (H), medium (M), or low (L)] were also determined. Immature reticulocyte fraction (IRF) was calculated as (M+H) percentage of reticulocytes. A wide range of OSA severity was found [apnoea/hypopnoea index (AHI): 44.3 +/- 30.4, range 0.3-105; sleep time spent at oxyhaemoglobin saturation <90%: 18.1 +/- 22.2%, range 0-81%]. Both reticulocyte coun...

Background Prior studies suggested that obstructive sleep apnea (OSA) promotes recurrence of arrhythmia in patients after atrial fibrillation (AF) ablation. Methods In this prospective, long-term, observational study, we enrolled 290 consecutive patients admitted for AF ablation. Prior to the ablation, all patients underwent a polygraphy sleep study for the diagnosis of OSA. After the procedure, patients were followed up for mean time of 30 months for AF reoccurrence. OSA was diagnosed when apnea–hypopnea index (AHI) was ≥5. Patients were subsequently divided into groups according to the OSA severity: mild OSA (AHI 5–15/h), moderate OSA (AHI >15 and ≤30/h), and severe (AHI >30/h). Results After excluding patients disqualified from the procedure , and those with central sleep apnea, the study population consisted of 251 patients, mean age 57.6 years [163 (64.9 %) male]. OSA was present in 115 (45.8 %) patients, while in 137 (54.6 %) cases, we observed reoccurrence of AF. Recurrence was more often in patients with, than without, OSA (65.2 vs. 45.6 %; p=0.003). We also observed that along with rising OSA severity rose also the number of patients in whom AF was detected during the follow-up period (45.6 vs. 66.2 vs. 57.6 vs. 81.8 %; p=0.005; for non-OSA, mild, moderate, and severe, respectively). Conclusions OSA is highly prevalent in AF patients. The presence of OSA lowers chances on successful AF ablation. Early screening, and treatment for OSA in AF patients, may improve low success rates of AF ablation procedures.

BACKGROUND: Obstructive sleep apnoea (OSA) in children has been causally implicated in neurobehavioural and cognitive dysfunction. Consequently, the American Academy of Paediatrics highlighted the need to study pertinent functional cognitive outcomes before and after treatment. However, neurocognitive function has thus far only been assessed by caregiver-completed questionnaires, which can be labour intensive and time consuming, such that the need for complementary and more objective measures has emerged. OBJECTIVE: The study aimed to identify electrophysiological correlates of neurocognitive alterations in children with OSA and investigate utility as a predictive tool. PATIENTS AND METHODS: Twenty-eight children (14 OSA and 14 matched controls) underwent overnight sleep studies and neurocognitive testing, as well as the oddball attention task while event-related potentials (ERPs) were recorded. ERPs were analysed using temporal principal components and source analyses that provided...

The increased genioglossus muscle (GGm) activity seen in obstructive sleep apnoea syndrome (OSAS) may lead to increased fatigability or longer recovery time of the tongue.Maximal force, endurance, and recovery times of the tongue, electromyogram (EMG) absolute value, and EMG spectral analysis of the GGm obtained during submaximal contractions were compared in eight individuals without chronic snoring and eight OSAS patients.Endurance

Eur J Clin Invest 2010; 40 (11): 968–975Eur J Clin Invest 2010; 40 (11): 968–975AbstractBackground  C-reactive protein (CRP) is recognized as a potential factor implicated in atherogenesis and associated cardiovascular morbidity. The aim of our study was to assess the CRP evolution during 1-year follow-up period in obstructive sleep apnoea (OSA) patients under CPAP treatment.Methods  Five hundred and twenty-eight patients with newly diagnosed moderate to severe OSA were included. CRP was assessed before CPAP initiation and at the 3rd, 6th and 12th month of the follow-up period. Patients were divided into good and poor CPAP compliance groups.Results  A significant reduction in CRP levels was observed after CPAP therapy (0·74 ± 0·62 mg dL−1 vs. 0·31 ± 0·29 mg dL−1, P < 0·001) in the whole patient group. The evolution of CRP values showed a gradual decrease at 3 months with a steep decline at 6 months, reaching a plateau after this time point. When the patients were divided into those with good and poor compliance with CPAP therapy, the above CRP evolution pattern was observed only in the former group.Conclusion  Good CPAP compliance results in a significant CRP reduction. To achieve the best positive impact on cardiovascular morbidity and mortality, a time period of at least 6 months of CPAP use is required.Background  C-reactive protein (CRP) is recognized as a potential factor implicated in atherogenesis and associated cardiovascular morbidity. The aim of our study was to assess the CRP evolution during 1-year follow-up period in obstructive sleep apnoea (OSA) patients under CPAP treatment.Methods  Five hundred and twenty-eight patients with newly diagnosed moderate to severe OSA were included. CRP was assessed before CPAP initiation and at the 3rd, 6th and 12th month of the follow-up period. Patients were divided into good and poor CPAP compliance groups.Results  A significant reduction in CRP levels was observed after CPAP therapy (0·74 ± 0·62 mg dL−1 vs. 0·31 ± 0·29 mg dL−1, P < 0·001) in the whole patient group. The evolution of CRP values showed a gradual decrease at 3 months with a steep decline at 6 months, reaching a plateau after this time point. When the patients were divided into those with good and poor compliance with CPAP therapy, the above CRP evolution pattern was observed only in the former group.Conclusion  Good CPAP compliance results in a significant CRP reduction. To achieve the best positive impact on cardiovascular morbidity and mortality, a time period of at least 6 months of CPAP use is required.

Insomnia and Obstructive Sleep Apnoea Hypopnea Syndrome (OSAHS) are the two most common sleep disorders, and both have significant associated health costs. Despite this, relatively little is known about the prevalence or impact of insomnia in those with OSAHS, although a recent study suggested there may be substantial comorbidity between these disorders [Chest 120 (2001) 1923-9]. The primary aim of this study was to further explore the prevalence of insomnia in OSAHS. A secondary aim was to assess the effect of factors that may impact on both conditions, including mood and sleep-beliefs. Consecutive patients referred to an accredited Sleep Investigations Unit [n = 105] completed a brief standardized battery of validated questionnaires assessing sleep-related variables and mood. Results showed a high rate of prevalence of clinical insomnia in this OSAHS population, and a strong positive correlation between OSAHS and insomnia symptom severity. Further, OSAHS patients with comorbid ins...