Is Obsessive-Compulsive symptomatology a risk factor for Alzheimer-type dementia?

In the present study, we hypothesized that lifetime Obsessive-Compulsive (OC) symptomatology would be risk factors for the development of Alzheimer׳s disease (AD). For this aim, first we compared 39 patients with AD and 30 age and gender matched control subjects. We have found that lifetime and current OC symptoms (OCs) and comorbid diagnosis of Obsessive-Compulsive Personality Disorder in AD patients were significantly more prevalent than in control group. AD patients had more likely to have lifetime and current hoarding, and checking obsessions compared to controls. The rate of lifetime and current hoarding, and checking compulsions also appeared to be higher in AD patients in comparison to control subjects. Hoarding and checking obsessions, and compulsions seemed to proceed through the dementia in contrast to other OCs. The mean number of lifetime compulsions seemed to predict the diagnosis of AD. When we compared AD patients with and without OCs, we have found that OC symptomatology prior to AD did not cause an earlier onset of dementia and more severe cognitive impairment. Further longitudinal clinical, genetic and neuroimaging investigations are required to determine if lifetime presence of OCs would predispose to the development of later AD.