User:Mr. Ibrahem/Dementia with Lewy bodies

Dementia with Lewy bodies (DLB) is a type of dementia accompanied by changes in sleep, behavior, thinking, movement, and automatic bodily functions. Memory loss is not always an early symptom. The disease worsens over time and is usually diagnosed when cognitive decline interferes with normal daily functioning. Heart function and every level of gastrointestinal function—from chewing to defecation—can be affected, constipation being one of the most common symptoms. Low blood pressure upon standing can also occur. It can affect behavior; mood changes such as depression and lack of interest are common.

The exact cause is unknown, but involves widespread deposits of abnormal clumps of protein in neurons of the diseased brain. Most people do not have affected family, although occasionally it runs in a family. Known as Lewy bodies (discovered in 1912 by Frederic Lewy) and Lewy neurites, these clumps affect both the central nervous system and the autonomic nervous system. REM sleep behavior disorder (RBD)—in which people lose the muscle paralysis that normally occurs during REM sleep and act out their dreams—is a core feature. RBD may appear years or decades before other symptoms. Other core features are visual hallucinations, marked fluctuations in attention or alertness, and parkinsonism (slowness of movement, trouble walking, or rigidity). A presumptive diagnosis can be made if several disease features or biomarkers are present; the diagnostic workup may include blood tests, neuropsychological tests, imaging, and sleep studies. A definitive diagnosis usually requires an autopsy. Together with Parkinson's disease dementia, DLB is one of the two Lewy body dementias.

There is no cure or medication to stop the disease from progressing, and people in the latter stages of DLB may be unable to care for themselves. Treatments aim to relieve some of the symptoms and reduce the burden on caregivers. Medicines such as donepezil and rivastigmine are effective at improving cognition and overall functioning, and melatonin can be used for sleep-related symptoms. Antipsychotics are usually avoided, even for hallucinations, because severe and life-threatening reactions occur in almost half of people with DLB, and their use can result in death. Management of the many different symptoms is challenging, as it involves multiple specialties and education of caregivers.

DLB is a common form of dementia, but the number of people affected is not known accurately and many diagnoses are missed. It typically begins after the age of fifty and people with the disease live about eight years after diagnosis. The disease was first described by Kenji Kosaka in 1976.