Sleep Medicine Research Research Articles

Outcome measurement in sleep medicine practice and research. Part 1: assessment of symptoms, subjective and objective daytime sleepiness, health-related quality of life and functional status.

The documentation of treatment outcomes has gained increased importance as those responsible for paying for healthcare focus on the delivery of cost-effective care. The practitioner and researcher, challenged with documenting the clinical significance of their endeavors, must depend on conceptually appropriate, valid and reliable instruments. Outcomes of particular relevance for sleep disorders include self-reported general symptoms, subjective and objective daytime sleepiness, neurobehavior, health-related quality of life (HRQL) or functional status, incidence of accidents and cardiovascular morbidity, and health care utilization and cost. This paper will limit its focus to the outcomes of self-reported general symptoms, subjective and objective daytime sleepiness, and HRQL or functional status. In addition to describing measures that could be applied to evaluate these outcomes, this paper will also discuss factors affecting the selection of outcome measures for use in research and practice, and consider evidence generated with the application of these instruments in research. Reductions in self-reported symptoms, such as snoring and daytime hypersomnolence following treatment, have been documented with the application of measures with strong psychometric properties such as the Survey Screen for Sleep Apnea and Epworth Sleepiness Scale. In addition to statistical reliability, calculation of the effect size and standardized response mean indicate that these changes are also clinically meaningful. Similar improvements have also been demonstrated using the Multiple Sleep Latency Test (MSLT), although the resulting increased latency has not typically been within normal values. Important improvements following treatment have been documented with the Maintenance of Wakefulness Test (MWT). Evidence suggests that the MWT may be more sensitive in situations, such as narcolepsy, where there are high levels of physiologic sleepiness, reserving the MSLT where the physiologic sleep tendency is more restricted, such as in obstructive sleep apnea (OSA). Patients>> perceptions of the benefit of treatment to their daily lives have been documented by such generic measures of HRQL, such as the SF-36 and Nottingham Health Profile. However, the impact of sleep disorders and the benefit of treatment on those aspects of daily behavior likely to be most affected have more clearly been demonstrated with the utilization of disease-specific HRQL measures such as the Functional Outcomes of Sleep Questionnaire and the Calgary Sleep Apnea Quality of Life Index. 2001 Harcourt Publishers Ltd

Peripheral database module for clinical management and research in sleep medicine

Hospital-wide information systems may provide economical solutions for communication processes or for documentation by means of centralized digital medical records. Within a large university hospital, however, there may be too many diverse subspecialties and too many special medical procedures to be supported comprehensively by a single database information system. A peripheral modular system has been tailored to the specific needs of a sleep disorder clinic as an adjunct to the main clinical information system. The client server application allows for automatic data acquisition by on-line devices and by a graphical user interface. It supports administrative tasks for patient management, specific encounter interactions and data retrieval for research. Performance and acceptance of the system was assessed during clinical use, revealing positive response by the users, also with respect to significant time savings. Our experience suggests that the concept of peripheral database modules as "satellites" to a main clinical system provides flexibility in design and implementation of the specialized databases while providing access to data of more general relevance via the main database.

The role of actigraphy in the evaluation of sleep disorders.

This paper, which has been reviewed and approved by the Board of Directors of the American Sleep Disorders Association, provides the background for the Standards of Practice Committee's parameters for the practice of sleep medicine in North America. The growing use of activity-based monitoring (actigraphy) in sleep medicine and sleep research has enriched and challenged traditional sleep-monitoring techniques. This review summarizes the empirical data on the validity of actigraphy in assessing sleep-wake patterns and assessing clinical and control groups ranging in age from infancy to elderly. An overview of sleep-related actigraphic studies is also included. Actigraphy provides useful measures of sleep-wake schedule and sleep quality. The data also suggest that actigraphy, despite its limitations, may be a useful, cost-effective method for assessing specific sleep disorders, such as insomnia and schedule disorders, and for monitoring their treatment process. Methodological issues such as the proper use of actigraphy and possible artifacts have not been systematically addressed in clinical research and practice.