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In response to Camilla Flinterman's request, here is the article on dementia: Cognitive Impairment & Dementia in Parkinson's Disease Many Parkinson's patients complain of slowness in thinking and word finding difficulties. Clinical research has demonstrated that this subtle form of cognitive impairment occurs in virtually all individuals with Parkinson's disease. These mild alterations in thought processes are relatively well tolerated by most patients, as they do not hinder day-to-day activities. Some Parkinson's patients incidentally report improvements in motivation and concentration when they take dopaminergic medications such as Sinemet (levodopa) but usually these medicines neither help nor hinder concentration and thinking. Dementia refers to cognitive impairment of sufficient magnitude to hinder daily activities or diminish the quality of the patient's life. Dementia is reported in approximately 20% of Parkinson's patients. It appears to be more common in late onset illness, i.e., after age 65. The dementia of Parkinson' s disease usually becomes apparent several years after the onset of the motor features of the illness. It usually takes the form of memory difficulties, distractibility, slowed thinking, and lack of motivation. Other aspects of dementia, such as onset early in the course of the illness, agitation, delusions, and language difficulties may indicate that the cause of the problem is not simply Parkinson's disease. In some instances, the physician will recommend brain scans and blood tests to search for other treatable causes for the cognitive decline such as vitamin B12 deficiency or thyroid disease. Other neurological disorders such as Alzheimer's disease can occur along with Parkinson's disease. There is a growing awareness of a condition termed "diffuse Lewy body disease." This refers to an illness which has some similarities to both Parkinson's and Alzheimer's disease. Cognitive impairment, delusions, hallucinations, and relatively mild parkinsonian motor features such as slowness and tremor are the hallmark of this condition. Postmortem brain examination reveals the characteristic microscopic Lewy body of Parkinson's disease scattered diffusely in cells throughout several brain regions. There are no specific treatments for Parkinson's dementia. Increased dosing of conventional antiparkinson drugs such as levodopa does not appear to benefit the dementia of Parkinson's disease. Some antiparkinson medications may actually accentuate cognitive impairment. This is particularly true of the anticholinergic drugs such as Artane® (trihexyphenidyl) and Cogentin®. Antidepressant drugs are sometimes prescribed to help with the apathy or lack of motivation commonly seen in Parkinson's dementia. There is often an element of depression in Parkinson's disease and severe depression can masquerade as dementia so that anti-depressant drugs are sometimes helpful. Behavioral management or memory aids can often prove useful in dementia. Memory aids can include large-print calendars, clocks, prominently posted lists, and large-print newspapers. Support organizations can help provide suggestions in this regard. Some physicians prescribe Alzheimer's disease drug therapies for Parkinson's dementia. These drugs include tacrine HCl (Cognex®) and Aricept®. There is no evidence that such compounds are effective in this setting. However, it should be recognized that some Parkinson's patients may actually develop Alzheimer's disease and, therefore, the medications may be helpful in that sub-group of patients. In addition, it is often argued that such drugs should be tried since they are relatively safe and because there are no alternative treatments proven to be effective. In the United States, a drug trial testing a new compound for the treatment of cognitive decline in PD is on going. There is clearly a desperate need for proven effective remedies for dementia in PD. by Jean Hubble, M.D. Ohio State University Parkinson's Center of Excellence