Movement disorders frequently fragment sleep sufficiently to cause excessive daytime sleepiness, but also have important indirect effects on sleep, which need to be treated appropriately. The ways in which these movement disorders influence sleep are described below.
1 Degenerative disorders disrupt sleep in a similar way to the normal changes seen in the elderly. Sleep efficiency and total sleep time are reduced with an increase in the number of arousals and sleep-stage transitions. Stages 3 and 4 NREM sleep are shortened.
These abnormalities may improve with drug treatment of the movement disorder.
2 There may be associated sleep disorders. Huntington's disease, for instance, is associated with periodic limb movements in sleep and RLS, and multiple system atrophy is associated with the REM sleep behaviour disorder. Children with tics are predisposed to sleep walk and talk.
3 Some disorders, particularly the degenerative ones, are associated with respiratory abnormalities such as obstructive or central sleep apnoeas which cause sleep fragmentation.
4 There may be indirect effects on sleep due to, for instance, dementia which alters the regulation of sleep. Changes in environmental stimuli such as a reduction in exposure to light may also affect sleep control, and other factors such as depression and sleep fragmentation due to discomfort and pain are features of many of these conditions, particularly Parkinsonism.
5 Drugs used therapeutically may help to relieve the movement disorder, but may induce other sleep disorders.
Was this article helpful?