A new study published recently in the Journal of Alzheimer’s Disease has identified cerebrovascular disease as a major determinant of psychosis in individuals with Alzheimer’s disease. The findings oppose some previous opinion that the mechanism underlying psychosis in Alzheimer’s patients is due to the characteristic brain deposits developed during the disease.
The team, based at St Michael’s Hospital (ON, Canada), analyzed data from 1073 individuals collected from the National Alzheimer’s Coordinating Centre database.
In the 890 patients clinically diagnosed with Alzheimer’s disease while alive, psychosis correlated with increased physical signs of the disease, including neuritic plaques and neurofibrillary tangles. In contrast, evaluation of the 728 individuals in which an Alzheimer’s diagnosis was confirmed through autopsy, patients with psychosis showed no increased physical evidence of Alzheimer’s disease. Psychosis did however correlate significantly with Lewy bodies in both groups.
Unexpectedly vascular risk factors, including hypertension, age at quitting smoking and diabetes, as well as evidence of cerebral injury, also played a clear role in the development of psychosis.
The study may have implications for the management of psychosis in Alzheimer’s patients, including caregiver burden as well as disease progression.