Sleep apnea and periodic movements in an aging sample.

Individuals 65 years of age and older were randomly selected, from a primarily white upper-class population, to participate in a study of sleep disorders in elderly adults. One hundred forty-five volunteers had a brief telephone interview, a home interview, and a portable sleep recording using the Medilog and Respitrace systems. By research classifications, we found that 18% of the elderly participants had sleep apnea (apnea index greater than 5), 34% had periodic movements in sleep (myoclonus index greater than 5) (PMS), and 10% had both sleep apnea and PMS. These were not clinical diagnoses. The home recording indicated that the individuals with PMS slept significantly less than other older adults.