Dementia with Lewy bodies (DLB) is the second most common cause of dementia in older people, accounting for approximately 130,000 individuals in the UK and affecting the lives of their carers and families as well. It is sometimes also referred to as Lewy body disease or Lewy body dementia.

Lewy bodies are deposits of abnormal proteins inside brain cells and are named after Dr. Friedrich Lewy who first discovered them under the microscope in 1912. Lewy bodies are associated with the death of brain cells and subsequent deterioration of the brain.

DLB shares characteristic symptoms of Alzheimer’s disease (AD) and Parkinson’s disease (PD), with both mental and motor problems. There are problems with memory, concentration and other cognitive abilities similar (but not identical) to AD and difficulties with balance, movement and autonomic functioning (bladder, bowel, blood pressure control) as in PD.

People with DLB characteristically experience dramatic swings in their level of alertness, fluctuating from clarity to confusion, often in a short period of time. Visual hallucinations are common in DLB, typically of people and animals, which are vivid. Although they may have other Parkinsonian symptoms, the tremor associated with PD is not always present. Because DLB, AD and PD share so many symptoms, diagnosis of DLB can be difficult and requires an experienced specialist e.g. in old age psychiatry or neurology. Accurate diagnosis is essential for successful treatment.

At present there is no cure for DLB but symptoms can often be alleviated. Research indicates that some AD drugs may be helpful for people with DLB. Parkinson’s drugs may help some people with the motor symptoms but can increase confusion in others. Prescribing should be started by a doctor with experience of DLB. Some types of drugs (antipsychotics) should not be given to people with DLB as they can be extremely harmful. Non-medical interventions such as a daily routine, physical activity where possible and changes to the environment are all helpful in managing daily life.