[Sleep problems in dementia].

Sleep disturbance is common in patients with dementia. Circadian rhythm sleep disorders are caused by the disturbance of sleep-wake regulation in the central nervous system, disturbed input into the sensory organs, and decreased social activities. Diurnal change of serum melatonin level in Alzheimer's disease showed decreased amplitude and shifted peak secretion. Age related sleep disturbances and sleep disorders due to the neurodegeneration including REM sleep behavior disorder also increase in dementia. Identifying and treating underlying sleep disorders along with therapeutic approach to circadian mechanism is effective. Treatment of circadian abnormality in dementia require light therapy and increased daytime activity. Use of oral melatonin is also effective for the improvement of nocturnal sleep. Treatment of sleep problems in dementia also contribute to the better management of dementia.

[Secondary restless legs syndrome].

Restless legs syndrome (RLS) is known to occur secondary to various medical conditions such as iron deficiency, pregnancy, end-stage renal disease, and neuropathy. Secondary RLS usually occurs later in the life and in the absence of a family history of RLS. Diagnosis of secondary RLS may be difficult, particularly in patients with neurological comorbidities. Sensory disturbance due to neurological disorder may mimic the symptoms of RLS symptom. In distinguishing between RLS and RLS mimics, neurophysiological findings, in addition to a detailed neurological examination, are helpful. Treatment of secondary RLS often requires management of the background medical condition. Iron supplementation is useful in patients with iron deficiency. Dopamine agonists are usually effective for both primary and secondary RLS; however, an increased dose of dopamine agonist may be necessary in some secondary RLS cases, particularly in uremic RLS. In patients with end-stage renal disease on hemodialysis, management of daytime symptoms, particularly during the hemodialysis sessions, may be necessary. Secondary RLS is still an unrecognized and underdiagnosed disorder. Medical practitioners should be aware of comorbid RLS in patients with neurological conditions that could be the cause of RLS.

A sleep disorders centre in the United Kingdom.

The demographic features of 296 patients who consulted a sleep disorders centre in the United Kingdom were reviewed. Diagnosis after a sleep study was mainly that of sleep-related breathing disorders; however, various other sleep disorders were also diagnosed. Considering that most sleep disorders are diagnosed only after sleep investigations, it should be emphasized that such a facility should be well prepared in undertaking not only polysomnography but also various sleep investigations, including multiple sleep latency testing and actigraphy. In addition, several treatment options, including sleep hygiene, light therapy, and behavioural therapy, should be available. Therefore, a sleep disorders centre needs to be operated by sleep specialists.