Comparison of hypopnea definitions in lean patients with known obstructive sleep apnea hypopnea syndrome (OSAHS)

Study objectives  

In the interest of improving inter-rater reliability and standardization between sleep laboratories, hypopnea definitions were recently changed to place less emphasis on arousal scoring and more emphasis on oxygen desaturations. We sought to determine whether these changes would affect detection and treatment of OSAHS in lean patients—a group known to desaturate less-than-obese patients.     

Scheduled Bright Light for Treatment of Insomnia in Older Adults

OBJECTIVES: To determine whether bright light can improve sleep in older individuals with insomnia.
DESIGN: Single-blind, placebo-controlled, 12-week, parallel-group randomized design comparing four treatment groups representing a factorial combination of two lighting conditions and two times of light administration.
SETTING: At-home light treatment; eight office therapy sessions.
PARTICIPANTS: Thirty-six women and fifteen men (aged 63.6±7.1) meeting primary insomnia criteria recruited from the community.
INTERVENTION: A 12-week program of sleep hygiene and exposure to bright (∼4,000 lux) or dim light (∼65 lux) scheduled daily in the morning or evening for 45 minutes.
MEASUREMENTS: Within-group changes were observed for subjective (sleep logs, questionnaires) and objective (actigraphy, polysomnography) sleep measures after morning or evening bright light.
RESULTS: Within-group changes for subjective sleep measures after morning or evening bright light were not significantly different from those observed after exposure to scheduled dim light. Objective sleep changes (actigraphy, polysomnography) after treatment were not significantly different between the bright and dim light groups. Scheduled light exposure was able to shift the circadian phase predictably but was unrelated to changes in objective or subjective sleep measures. A polymorphism in CLOCK predicted morningness but did not moderate the effects of light on sleep. The phase angle between the circadian system (melatonin midpoint) and sleep (darkness) predicted the magnitude of phase delays, but not phase advances, engendered by bright light.
CONCLUSION: Except for one subjective measure, scheduled morning or evening bright light effects were not different from those of scheduled dim light. Thus, support was not found for bright light treatment of older individuals with primary insomnia.     

Radiofrequency (pacing and thermic effects) in the treatment of sleep-disordered breathing

Radiofrequency, whether it is used for pacing or for its thermal liberation properties, has been investigated as a treatment for sleep-disordered breathing. Diaphragmatic pacing has a long history. The problems associated with pacing, which are related to patient selection, equipment failure, disturbances at the electrode/nerve interface, neuromuscular function failure, muscle fatigue, and the physiological consequences of stimulation, will have to be resolved with XIIth nerve stimulation. Radiofrequency thermal ablation has been applied on the tongue of an animal model. In man, turbinates, soft palate tissue and the base of tongue have been treated. These feasibility studies have demonstrated that obstructive sleep apnea syndrome and upper airway resistance syndrome can be completely controlled using radiofrequency thermal ablation in some subjects. These results can be obtained without complications related to speech, taste or swallowing. The treatment can be administered as an outpatient procedure, but many applications are needed, and treatment may span 6 months. Too high a level of radiofrequency will cause pain or otherwise avoidable complications. The determination of which patients will benefit most from these procedures will require further multi-center, placebo-controlled studies.     

The diurnal variability of ventricular premature depolarizations: influence of heart rate, sleep, and wakefulness

The relationships between ventricular premature depolarizations (VPDs) and heart rate (HR) were determined in 14 patients with ventricular arrhythmias and the influence of these relationships on the diurnal variability of ventricular arrhythmias was evaluated. The influence of sleep state, wakefulness, and level of activity on the frequency of VPDs was also studied. Subjects completed 48-72 h of ambulatory electrocardiographic monitoring and nocturnal sleep recordings. Plots of VPD frequency vs. HR were examined and subjects were categorized as HR-dependent if they manifested log-linear increase in VPDs with increasing HR and as HR-independent if no relation between VPD frequency and HR was detected. Sleep suppression of VPDs was observed in the HR-dependent group (p less than 0.05). The reduction in VPD frequency correlated with the reduction in HR and was independent of sleep state or wakefulness. No change in VPD frequency was observed during wakefulness, rapid eye movement sleep, or non-rapid-eye-movement sleep in the HR-independent group. The influence of level of activity on ventricular arrhythmia frequency was also assessed in seven subjects. Any decreases in VPD frequency observed during inactivity were associated with a decrease in HR. These observations suggest that HR is a major determinant of the diurnal variation of VPD frequency in a subset of patients with frequent VPDs.     

Obstructive sleep apneic patients have craniomandibular abnormalities

One hundred fifty-five unselected obstructive sleep apneic patients seen in succession had cephalometric roentgenograms and polygraphic recordings performed. These patients were compared to a group of 41 subjects who had consulted orthodontists for malocclusion and had no clinical indication of sleep apnea. The cephalometric landmarks were also compared to those published as normative data in the literature. The limits of "normalcy" were conservatively defined as mean +/- 2 standard deviations. Only two obstructive sleep apneic patients had normal cephalometric landmarks and 150 of the 155 patients had at least two significantly different landmarks from the normative data in the literature. The common findings were a retroposition of the mandible, a different cranial base flexure with a nasion-sella-basion angle more acute than expected, and a displacement of the hyoid bone to a lower position than expected. These combined changes reduced the space occupied by soft tissues anchored on the skull and mandible, and the length of the soft palate was increased.     

Respiratory and hemodynamic study during wakefulness and sleep in myotonic dystrophy.

Six young male patients with grade I (mild) myotonic dystrophy and a complaint of excessive daytime sleepiness were studied during wakefulness and sleep. Pulmonary function tests during wakefulness showed evidence of mild abnormality related to respiratory muscle weakness. During sleep, some patients developed a sleep apnea syndrome with high sleep Apnea Indices. There was no relation between hypoxic and hypercapnic ventilatory responses during wakefulness and sleep Apnea Indices. But hypoxemia and hypercapnia worsened considerably during REM sleep. Myotonic dystrophy patients with sleep apnea presented increased pulmonary and systemic arterial pressures during sleep. It was also during sleep that arrhythmias were observed.     

Asthma and Hypogammaglobulinemia: an Asthma Phenotype with Low Type 2 Inflammation

Purpose

Little is known about hypogammaglobulinemia (HGG) in asthma patients. No data are available on the characteristics of adult patients with asthma and HGG.

Methods

We conducted a retrospective monocentric study between January 2006 and December 2012. Asthma patients with a serum immunoglobulin (Ig) quantitative analysis were included and classified into two groups depending on their serum IgG concentration: presence or absence of HGG. Clinical, biological, functional, and radiologic characteristics were compared in univariate and multivariate analysis, using a logistic regression model.

Results

In univariate analysis, asthma patients with HGG (n?=?25) were older (58 years old?±?18 vs 49?±?18, p?=?0.04) and more frequently active or former smokers as compared to patients with normoglobulinemia (n?=?80) (56.0 vs 35.0 %, p?=?0.01). Total IgE?<?30 kUI/L was more frequently observed in patients with HGG (53.0 vs 18.3 %, p?=?0.01). HGG asthma patients had lower fraction of exhaled nitric oxide (p?=?0.02), blood eosinophilia (p?=?0.0009), and presented with more severe composite score for bronchiectasis (p?=?0.01). In multivariate analysis, asthma patients with HGG had increased risk of being smokers [OR?=?6.11 (IC 95 %?=?1.16–32.04)], having total IgE concentration?<?30 kUI/L [OR?=?12.87 (IC 95 %?=?2.30–72.15)], and a more severe composite score of bronchiectasis [OR?=?20.65 (IC 95 %?=?2.13–199.74)].

Conclusion

Asthma patients with HGG are older and more often tobacco smoker than asthma patients without HGG. These patients have low type-2 inflammation markers.

     

An epidemiologic study of sleep problems among adolescents in North Taiwan

Background and purposeTo investigate the prevalence of sleep problems and their association with daytime sleepiness among Taiwanese adolescents by use of a validated questionnaire.Patients and methodsThis is a cross-sectional, community based study with self-reported sleep questionnaires. Completed questionnaires from 1939 adolescent subjects from schools in Lin-Kou district (Taipei, Taiwan) (96.7% responded); 1906 valid questionnaires (62.3% girls) were analyzed. The randomly selected classes included elementary grade 6 (age range: 12–13 years), junior high school (age range: 14–16 years) and senior high school students (age range: 17–18 years).ResultThe mean sleep duration on weekdays was 7.35 ± 1.23 h and on weekends 9.38 ± 1.62 h. Weeknight sleep decreased significantly with increasing school grade (6.87 ± 1.14 h for high school seniors). There was a trend towards increased daytime sleepiness for students in higher school grade levels. Daytime sleepiness directly correlated with shorter total sleep time (TST) on weekdays, longer TST on weekends, snoring, insomnia and nightmares. Coffee intake, smoking, periodic leg movement/restless legs syndrome, body mass index (BMI), mouth breathing and breathing problems were indirect factors that induced daytime sleepiness. Pearson correlation showed no significant correlation between the TST during the weekday and BMI (?0.047, p = 0.079) or body weight (BW) (?0.048, p = 0.072). But it showed significant negative correlation (?0.103, p = 0.0001) for increasing total sleep time on the weekend and decreasing BMI.ConclusionsDaytime sleepiness correlated with the shorter TST on weekdays, longer TST on weekends, snoring, insomnia and nightmares. There is no significant correlation between the weekday TST and BMI or BW. Meals and food intake of children are still traditional and have not changed as much in Taiwan as in some other western countries, and compared to a similar survey performed 12 years ago in Taiwan among junior high school students, sleep duration was not significantly different but reduced due to school demands.