Illusions and Delusion in the Elderly-Part I

The illusion of visitors is a common occurrence amongst the elderly. It may be associated with any of the following: impairment in visual acuity, disturbance in visual association, dysfunction in the temporal or frontal areas of the brain due to dementia or stroke, and/or medication toxicity. In many cases, a combination of these factors interacts to cause the visual hallucinations and/or delusions.

In 1769, Charles Bonnet, a Swiss philosopher and naturalist, published an account of visual hallucination in his psychologically normal, visually impaired grandfather. Since then, numerous reports have been made of visual hallucinations accompanying visual loss. Conditions such as cataracts, glaucoma, macular degeneration and diabetic retinopathy are common in the elderly. The visual hallucination can be benign, simple visual distortions, or elaborate and at times menacing visual hallucinations and delusions.

Hallucinations and delusions commonly occur in conjunction with dementia. J L Cummings et al studied hallucinations and delusions in 30 patients with dementia of the Alzheimer's Type (DAT) and 15 patients with multinfarct dementia (MID). Delusions were found in 30% of DAT and 40% of MID patients. Most delusions were of the paranoid type, and involved elementary misbeliefs, such as theft of possessions.

Visual hallucinations and/or delusions occur in at least half of patients with senile dementia and no previous psychiatric history. In degenerative dementia, such as Alzheimer's disease, these symptoms are usually transient phenomena, occurring in the early to middle stages of the illness and disappearing when cognitive deficits become severe. In cerebrovascular disease, it can occur acutely and persist for months or even years. There may be an association between development of delusions and pathology of the frontal, right temporal and parietal lobes of the brain.

Families need to know more about the nature of these phenomena and their non-volitional nature to develop more realistic expectations of behavior.

Delusions are commonly seen in conjunction with dementia. Simple delusions of theft and vague suspicions directed at relatives are commonly observed. It usually represents an attempt by the amnesic patient to explain the loss of articles that have been misplaced. Unable to remember losing the object, the demented patient imagines an explanation involving theft by someone close at hand, often a caregiver. Many of the delusions that evolve from the visual experience of imaginary visitation can be viewed as an attempt to make sense out of bizarre. This input nonetheless seems real to the patient (if there are strangers in the house, they must be there for a purpose).

Dementia is overwhelmingly a condition associated with aging and predominately affects the elderly. Truly reversible causes of dementia are quite unusual and the common causes (AD, dementia caused by cerebrovascular diseases, Parkinson's disease) are chronic diseases. These conditions will not go away. There is a great need to seek treatment that will minimize the effects of the disease.

Hallucinations and dementia are hard to take when seen in our parents. Trying to persuade the individual that they are not seeing these things may be counter-productive. Professional intervention can help deal with these situations.

Illusions and Delusions-Part II-Dementia and Delirium
Illusions and Delusions-Part III-Medical Condition Delirium


By Harold Rubin, MS, ABD, CRC, Guest Lecturer

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