Journals of Gerontology Series A: Biological Sciences and Medical Sciences, Vol 53, Issue 5 M391-M394, Copyright © 1998 by The Gerontological Society of America
Periodic leg movements during sleep and sleep disturbances in elders
SD Youngstedt, DF Kripke, MR Klauber, RS Sepulveda and WJ Mason
Department of Psychiatry, University of California, San Diego, USA. syoungstedt@ucsd.edu
BACKGROUND: Periodic limb movements in sleep (PLMS) are an increasingly
pervasive disturbance for aging adults. The aims of this experiment were:
(a) to describe the index of periodic limb movements in sleep (myoclonus
index [MI] in elderly subjects with complaints of poor sleep or depression
(N = 22; 68 +/- 5.5 SD years); and (b) to correlate MI with sleep history,
depression scores, and objective and subjective indices of sleep. METHOD:
Sleep and leg movements were assessed for 5 consecutive nights.
Between-subjects, nonparametric correlations were examined between mean MI
and sleep history, depression scores, and objective and subjective sleep
characteristics. Associations among within-subject night-to-night
variabilities of MI, objective, and subjective variables were examined with
repeated measures ANCOVA, entering MI as a covariate. RESULTS: A remarkably
high level of MI was found (median 25.8 events per hour; 86% of subjects
> 5). Nevertheless, no associations were found between MI and sleep
disturbance measures. CONCLUSION: These results extend previous reports
that PLMS are remarkably persuasive in elderly volunteers and support other
reports questioning whether there is a distinct PLMS syndrome.
