Visceral theory of sleep states that the same brain neurons, which process external information in wakefulness, during sleep switch to the processing of internal information coming from various visceral systems. Here we hypothesize that a failure in the commutation of exteroceptive and interoceptive information flows in the brain can manifest itself as a mental illness.

Extraintestinal manifestations of Crohn's disease (CD) have not previously included the central nervous system (CNS). Restless legs syndrome (RLS) is a CNS disorder that is either idiopathic or secondary to a number of diseases. The aim of this study was to determine if RLS was associated with CD because both are associated with iron deficiency, inflammation, and bacterial overgrowth.

Consecutive CD outpatients (N = 272) were prospectively surveyed at 4 centers for criteria for RLS. Incidence (having RLS at any point in time), prevalence (having RLS at time of survey), clinical characteristics, risk factors, and potential qualitative relationship between RLS and gastrointestinal symptoms were queried.

The incidence of RLS in patients with CD was 42.7%. Prevalence was 30.2% compared with 9% of spouses. CD patients with and without RLS had a mean age of 46.8 versus 42.6 years, small intestine involvement in 77.9% versus 66.7%, colon involvement in 39.7% versus 63.2%, and prior iron deficiency anemia in 49.3% versus 33.1%. There was no difference between the CD groups with respect to current iron deficiency, RLS family history, or rare prevalence of concomitant RLS disorders. In 91.8% of patients with RLS and CD, RLS started during or after the onset of CD diagnosis. Among 73 patients with RLS, 67 (44.5%) stated there was a relationship between qualitative RLS symptom improvement with overall CD symptom improvement.

These results demonstrate that RLS occurs frequently in CD and appears to be a possible extraintestinal manifestation. The potential relationship of RLS with CD activity warrants further investigation.

Sleep disorders are common and may result in significant morbidity. Examples of the major sleep disturbances in primary care practice include insomnia; sleep-disordered breathing, such as obstructive sleep apnea; central nervous system hypersomnias, including narcolepsy; circadian rhythm sleep disturbances; parasomnias, such as REM sleep behavior disorder; and sleep-related movement disorders, including restless legs syndrome. Diagnosis is based on meticulous inventory of the clinical history and careful physical examination. In some cases referral to a sleep laboratory for further evaluation with polysomnography, a sleep study, is indicated.

Symptoms are increasingly recognized as problematic for patients with end-stage renal disease (ESRD) treated with dialysis. Sleep disorders are common in ESRD patients treated with dialysis and are associated with patients' perceptions of quality of life, assessed by diverse measures, as well as depressive affect. Sleep disorders appear to be equally prevalent in peritoneal dialysis (PD) and hemodialysis (HD) patients. Treatment for sleep disorders in dialysis patients depends on establishing the diagnosis, often in a sleep laboratory, using polysomnography. Reversing coexistent medical and psychological disorders is important. The sleep apnea syndrome (SAS) can be treated with continuous positive airway pressure in dialysis patients, but conventional hemodialytic techniques have little effect on its severity. In contrast, nocturnal HD and transplantation appear to have important beneficial effects on sleep disordered breathing in ESRD patients. Although pain has been appreciated as a problem for ESRD patients for more than 20 years, few studies exist on this subject. Pain appears to be an underappreciated problem for ESRD patients. More research must be performed on the problem of pain in patients with chronic kidney disease (CKD).

Patients with pulmonary hypertension (PH) have an increased prevalence of risk factors for restless legs syndrome (RLS). We performed a cross-sectional study to determine the prevalence and characteristics of RLS in this population.

Patients filled out two questionnaires during a visit: (1) a diagnostic tool for RLS, based on the core clinical features; and (2) a 10-question rating scale used to assess severity. Data were obtained by medical record review with regard to demographics, characteristics of PH and known RLS risk factors.

Restless legs syndrome was found in 43.6% (24 of 55) (mean age +/- SD: 49 +/- 14 years; 41 women, 14 men) of patients and 54% of these had moderate or severe RLS. Patients with RLS were younger but gender differences were not appreciated. Presence of RLS did not correlate with measures of PH severity; however, patients with RLS were more likely to have a better 6-minute walk distance (p = 0.015) and lower BNP level (p = 0.07) and less likely to be WHO Class IV or require oxygen during the 6-minute walk test. Patients with a history of hypothyroidism (67%; p = 0.04) and those on opioids for relief of leg pain (69%) were more likely to have RLS.

Patients with PH had a very high prevalence of RLS and most had moderate or severe symptoms. RLS was more common in more active patients and those who were hypothyroid or on opioids for relief of leg pain. Patients with PH should be screened for RLS because good treatment options are available.

Given the increased incidence of steroid-induced diabetes and drug-induced anemia, renal dysfunction and neuropathy, we believed that lung transplant recipients would be at an increased risk of developing restless legs syndrome (RLS). We performed a cross-sectional, observational study to determine the prevalence and characteristics of RLS in this population.

Patients filled out two questionnaires during a routine visit: (1) a diagnostic tool for RLS, based on the core clinical features; and (2) a 10-question rating scale used to assess severity. Data were obtained by medical record review with regard to demographics, lung transplant characteristics and known risk factors for RLS.

Forty-two lung transplant recipients (age 46.6 +/- 15.4 years [mean +/- SD]; 24 women, 18 men) without a family history of RLS were recruited. RLS was found in 47.6% (20 of 42) of the patients and 80% had moderate or severe RLS. Seventy-five percent of those with RLS were women (p = 0.03). RLS patients had a serum calcium level that was higher than those without RLS (p = 0.05) and were more likely to be recipient (p = 0.02) or donor positive (p = 0.07) for cytomegalovirus (CMV). All 4 hypothyroid patients on replacement therapy were in the RLS group. The prevalence of diabetes mellitus and chronic renal failure were not significantly different between the RLS and non-RLS groups.

There was a very high prevalence of RLS in our lung transplant population and most patients had moderate or severe symptoms. RLS patients were more likely to be women, donor or recipient positive for CMV, hypothyroid, and to have an elevated serum calcium level.

Restless legs syndrome (RLS) is a common condition characterized by an unpleasant urge to move the legs that usually occurs at night and may interfere with sleep. The medications used most commonly to treat RLS include dopaminergic drugs (levodopa, dopamine agonists), benzodiazepines, and narcotic analgesics. We report the cases of 2 patients with RLS who illustrate the problems of tolerance (declining response over time) and augmentation (a worsening of symptoms due to ongoing treatment) that can complicate the pharmacotherapy of RLS. We discuss the optimal management of RLS and propose strategies to overcome tolerance and augmentation such as a rotational approach among agents from different classes.

The authors reviewed the clinical features, epidemiology, pathogenesis and risk factors, medical management, dental findings and dental management of patients with restless legs syndrome (RLS).

The authors conducted a MEDLINE search for the years 2000 through 2004 using the key terms "restless legs syndrome," "epidemiology," "pathophysiology," "treatment" and "dentistry." They selected articles published in English in peer-reviewed journals for further review, and they gave preference to articles reporting randomized controlled trials.

RLS is a neurological disorder that is characterized by unpleasant sensations in the legs that occur at rest, especially at bedtime. These symptoms cause an irresistible urge to get out of bed and move the legs to relieve the discomfort, thereby delaying sleep onset and resulting in fatigue and dysphoria the next day.

The prevalence of dental disease may be extensive in patients with RLS because of diminished salivary flow resulting from the medications used to treat RLS. Patient education, saliva substitutes and anticaries agents are indicated. Special precautions must be taken when prescribing or administering sedative-hypnotic agents that are likely to have adverse reactions with the medications used to treat RLS.

We present a case report of an acute episode of restless legs syndrome that interfered with the performance of a diagnostic imaging procedure of the cervical spine. The patient had a 19-yr history of restless leg syndrome with periodic limb movements during sleep. Treatment with additional sedation and opioids did not alleviate the leg movements. IV administration of 1 mg of physostigmine eradicated all extraneous leg motion.