Influence of Sleep Stage on LH Pulse Initiation in the Normal Late Follicular Phase and in Polycystic Ovary Syndrome.

Objective: During the early follicular phase, sleep-related luteinizing hormone (LH) pulse initiation is positively associated with brief awakenings but negatively associated with rapid eye movement (REM) sleep. The relationship between sleep architecture and LH pulse initiation has not been assessed in other cycle stages or in women with polycystic ovary syndrome (PCOS).

Design And Methods: We performed concomitant frequent blood sampling (LH pulse analysis) and polysomnography on 8 normal women (cycle day 7-11) and 7 women with PCOS (at least cycle day 7).

Airway turbulence and changes in upper airway hydraulic diameter can be estimated from the intensity of high frequency inspiratory sounds in sleeping adults.

Obstructive sleep disordered breathing can cause death and significant morbidity in adults and children. We previously found that children with smaller upper airways (measured by magnetic resonance imaging while awake) generated loud high frequency inspiratory sounds (HFIS, defined as inspiratory sounds > 2 kHz) while they slept. The purpose of this study was (1) to determine what characteristics of airflow predicted HFIS intensity, and (b) to determine if we could calculate changes in hydraulic diameter (D) in both an in vitro model and in the upper airways of sleeping humans.

Movements during sleep correlate with impaired attention and verbal and memory skills in children with adenotonsillar hypertrophy suspected of having obstructive sleep disordered breathing.

Background: Children with obstructive sleep disordered breathing (OSDB) have both impaired cognitive performance and frequent movements during sleep. It is not known whether movements during sleep are related to cognitive function.

Methods: We studied 56 children with adenotonsillar hypertrophy suspected of having OSDB with actigraphy for six consecutive days and nights, followed by cognitive and performance tests.

Sleep assessment using a passive ballistocardiography-based system: preliminary validation.

Quantitative sleep analysis through the use of polysomnography is a well established standard. Finding new ways to approach this, especially over multiple nights, is becoming more important due to a growing recognition of adverse effects from poor sleep and sleep disorders. The Non-Invasive Analysis of Physiological Signals (NAPS) system is a ballistocardiography-based monitoring system developed to measure heart rate, breathing rate and musculoskeletal movement that shows promise as a general sleep analysis tool.

Development and preliminary validation of heart rate and breathing rate detection using a passive, ballistocardiography-based sleep monitoring system.

Techniques such as ballistocardiography (BCG) that can provide noninvasive long-term physiological monitoring have gained interest due to a growing recognition of adverse effects from poor sleep and sleep disorders. The noninvasive analysis of physiological signals (NAPS) system is a BCG-based monitoring system developed to measure heart rate, breathing rate, and musculoskeletal movement that shows promise as a general sleep analysis tool. Overnight sleep studies were conducted on 40 healthy subjects during a clinical trial at the University of Virginia.

Reduced time in bed and obstructive sleep-disordered breathing in children are associated with cognitive impairment.

Objective: The purpose of this study was to determine if reduced time in bed as well as the degree of obstructive sleep-disordered breathing predicted the risk of impaired cognitive function in children with adenotonsillar hypertrophy suspected of having obstructive sleep-disordered breathing.

Design: We studied 56 children, aged 6 to 12 years, with adenotonsillar hypertrophy referred for suspected obstructive sleep-disordered breathing. Children were given a sleep diary and underwent wrist actigraphy for 6 consecutive days and nights.

Cognitive function and behavior of children with adenotonsillar hypertrophy suspected of having obstructive sleep-disordered breathing.

Objective: The purpose of this study was to determine whether risks of impaired cognitive function could be predicted for children or groups of children with adenotonsillar hypertrophy who were suspected of having obstructive sleep-disordered breathing, from historical and polysomnographic variables used separately or in combination.

Methods: We studied 114 consecutive 6- to 12-year-old children with adenotonsillar hypertrophy, who were referred because of suspected obstructive sleep-disordered breathing, with questionnaires, assessment of tonsil size, general and memory cognitive tests, and attended polysomnography with the use of nasal pressure recording to detect flow.

Results: There were important significant relationships between snore group (snored every night versus less often), sleep efficiency, and race and 2 of 3 general cognitive tests (vocabulary and similarities).

Increases in overweight after adenotonsillectomy in overweight children with obstructive sleep-disordered breathing are associated with decreases in motor activity and hyperactivity.

Objective: To examine the effect of adenotonsillectomy (T&A) in children with obstructive sleep-disordered breathing on growth, hyperactivity, and sleep and waking motor activity.

Methods: We studied 54 children who were aged 6 to 12 years and had adenotonsillar hypertrophy and an obstructive apnea-hypopnea index of > or =1 before and 12 months after they all received adenotonsillectomy (T&A). We measured their height, weight, percentage overweight (patient BMI - BMI at 50th percentile)/BMI at 50th percentile x 100) and obtained a hyperactivity score from parent report on a standardized behavior questionnaire scale.

An upper airway resonator model of high-frequency inspiratory sounds in children with sleep-disordered breathing.

The goal of this study was to determine how high-frequency inspiratory sounds (HFIS) are generated by sleeping children with obstructive sleep-disordered breathing (OSDB). We hypothesized that HFIS are generated when a high-velocity jet of air, generated by a narrowed upper airway, induces the upper airway to act as a resonating chamber. We tested two predictions of this hypothesis: 1) the upper airway is narrowed in children who make HFIS and 2) the length of the upper airway, calculated from HFIS harmonic intervals, is similar to that calculated from magnetic resonance imaging (MRI) scans.

Children with obstructive sleep-disordered breathing generate high-frequency inspiratory sounds during sleep.

Study Objectives: We observed that some children with adenotonsillar hypertrophy and obstructive sleep-disordered breathing (SDB) make high-frequency inspiratory sounds (HFIS) during sleep. Our objective was to determine whether HFIS occur in most children with obstructive SDB and adenotonsillar hypertrophy and whether adenotonsillectomy reduces HFIS.

Design: Prospective consecutive-entry trial.