Percentile Reference Charts for Selected Sleep Parameters for 20- to 80-Year-Old Healthy Subjects from the SIESTA Database.

One of the aims of the SIESTA project was to establish a normative database of sleep parameters for healthy and sleep-disturbed patients. Reference data for sleep parameters in non-sleep-disturbed subjects are scarce and usually refer to means and standard deviations. However, since most of the parameters do not follow a Gaussian distribution, percentiles of the distribution provide more detailed information.The present results are based on data from 198 healthy, non-sleep-disturbed subjects (104 females) in the age range of 20 to 95 years. For every subject, two consecutive nights were polysomnographically recorded in one of the eight participating clinical centres. Percentile charts were created on the basis of moving averages computed for 10 year age intervals with the presented age being the midpoint of the underlying interval. The resulting percentile curves were smoothed by a spline function. Since sample size in the oldest age groups is comparatively small, the percentile curves are restricted to the age range of 20 to 80 years.Percentile curves have been created for the parameters sleep period time (SPT), total sleep time (TST), sleep onset latency, REM sleep latency, sleep efficiency index, and percentages of NREM1, NREM2, REM sleep, SWS, and WAKE (with reference to SPT). The charts reflect the known changes of sleep parameters with age, e.g. decrease of TST and sleep efficiency with increasing age.The reference charts are intended to be a helpful tool to evaluate selected aspects of sleep quality in sleep-disturbed patients. [ABSTRACT FROM AUTHOR]