Posted by Ted (152.163.207.74) on July 11, 2000 at 22:48:10:
Clinical Frontiers in the Sleep/Psychiatry Interface
[Psychiatry Treatment Updates - © 1999 Medscape, Inc.]
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TABLE OF CONTENTS REFERENCES
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Clinical Issues in Pain and Sleep
Fifty to seventy percent of pain patients suffer from sleep disturbance. Indeed, pain may be the most common cause of secondary sleep disturbance. Conversely, sleep restriction may provoke pain (especially headaches) and sleep disturbances can decrease pain tolerance. Similar circular relationships may exist between sleeplessness and mood disorders.[17-19] The direction of causality is not always clear, according to Dr. Mitchell Cohen, who presented the portion of the symposium on pain and sleep.
It has been suggested that sleep disturbance and depression may become self-sustaining causes of pain in the central nervous system. Therefore, identification and management of sleep disturbances as well as their psychiatric correlates may be of value in the overall management of pain syndromes and of psychiatric syndromes.
The most frequent sleep-related difficulties in pain patients are initial insomnia, frequent awakenings, decreased sleep duration, daytime sleepiness or fatigue, and nonrestorative sleep. These sleep problems often have a multifactorial pathogenesis. Some of these factors are psychiatric disorders, such as depression and anxiety, and medication effects; others include behavioral causes, such as increased bedroom time, increased repertoire of bedroom activities, decreased aerobic exercise, altered daily schedule, and altered sleep/wake cycle.
Alpha-delta intrusions in non-REM sleep (waking intrusions into deep sleep) are common in patients and have been observed in fibromyalgia, rheumatoid arthritis, heterogeneous pain disorders such as back pain and headaches, and insomnia.[20,21] Some have hypothesized that these intrusions may be responsible for the common complaints of malaise and fatigue.[22] Experimentally induced intrusions into non-REM sleep among healthy volunteers resulted in musculoskeletal tenderness, which resolved after 2 nights of undisturbed sleep. This study suggests the potential salutary effects that restoring sleep may have in pain patients.
Pain disorders commonly associated with sleep disorders include:
heterogeneous pain
rheumatoid arthritis, headaches (migraine, cluster, and tension)
osteoarthritis
fibromyalgia
Heterogeneous Pain
In a study conducted by Dr. M. Cohen and colleagues, the investigators found that among 41 heterogeneous pain center patients referred to psychiatry and behavioral medicine for consultation and management, 72% surpassed the threshold for clinical concern regarding specific sleep disorders including sleep apnea syndrome and periodic limb movement disorder, among others. In this sample, mood and sleep measures were correlated. However, the pain and sleep measures were not correlated. Furthermore, sleep findings did not correlate with low back pain or neuropathic pain when the data were subjected to regression analysis. Another study of heterogeneous pain patients[23] found that pain duration and intensity were correlated with decreased sleep, impaired sleep quality, and delayed sleep onset.
Headaches
Headaches are the most commonly reported pain complaint in the population (Schoenen et al., Textbook of Pain, 1994) and are often associated with sleep disturbance (Paiva et al., Headache Quarterly, 1992, 1994). Sleep disorders such as sleep apnea are found among headaches patients at rates greater than what is found in the general population (ie, 17%).[24] In addition, decreased and excessive sleep are associated with cluster headaches.[25] It is also known that the treatment of sleep disorders decreases headache complaints.[24] The implications for treatment are clear.
Rheumatoid Arthritis
Arthritic pain may be the most common cause of secondary sleep disturbance.[26] It has been observed that rheumatoid arthritis (RA) patients report a 60% or greater prevalence of sleep disorders. In fact, rheumatologists use sleep as one of the five factors to gauge relapse or remission in their arthritic patients; fatigue is considered a marker of disease activity while the absence of fatigue is considered to indicate remission.
Pharmacotherapy
General principles of pharmacotherapy in this population include:
treat comorbid psychiatric disorders
if possible, avoid sleep-disrupting medications (eg, traditional benzodiazepines and older SSRIs as well as antidepressants in bipolar I or II patients)
use sleep-friendly antidepressants (eg, nefazodone, trazodone, mirtazapine, TCAs)
consider new short-acting hypnotics (eg, zolpidem, zaleplon)
consider antiepileptic agents such as gabapentin or valproic acid (gabapentin is calming and acts as a hypnotic; valproic acid is sedating and may work well for headaches)
consider psychostimulants for severe daytime fatigue
Cognitive-behavioral Therapy
Cognitive behavioral therapy (CBT) may be useful in addressing basic sleep hygiene in pain patients. Patients should be instructed to eliminate caffeine, alcohol, and nicotine, to exercise early in the day, and to avoid activities that consistently increase pain. Restricting sleep with a gradual increase in sleep time is also an effective tool. Other helpful strategies include:
stimulus control
rebuilding a consistent daily activity pattern (eg, instruct the patient not to clean the whole house at once)
rebuilding a normalized sleep-wake cycle
addressing ergonomic/environmental issues (eg, sleeping position, pillow type, mattress type, and room temperature)
phototherapy
increasing aerobic activity (and address fear of movement)
increasing pain coping and acceptance
Dr. Cohen concluded his remarks by emphasizing that sleep disturbances are prominent in patients with chronic pain, despite the fact that they are often underevaluated and undertreated. Psychiatric conditions such as depression and anxiety are often linked with pain; depression, anxiety, and pain may also play a role in producing or sustaining sleep disturbance. Because sleep disturbance, like pain, may become chronic and take on independent CNS pathophysiology, it is critical that it be treated quickly and effectively.