New-onset criminal behavior in adults may be an early manifestation of behavioral variant frontotemporal dementia (bvFTD) or semantic variant of primary progressive aphasia (svPPA), according to a retrospective review of 2,397 patients followed from 1999 to 2012.
Researchers reviewed medical records and patient notes and found the percentage of those who had a history of criminal behavior emerge during their illness varied by diagnosis as follows:
| Total Cases | Percent with Criminal Behavior | |
| All Subjects | 2,397 | 8.5% |
| Alzheimer Disease | 545 | 7.7% |
| bvFTD | 171 | 37.4% |
| svPPA | 89 | 27% |
| Huntington Disease | 30 | 20% |
In subjects diagnosed with bvFTD, criminal behaviors included theft, traffic violations, sexual advances, trespassing, and public urination, while those diagnosed with Alzheimer were more likely to commit traffic violations related to cognitive impairments.
The authors suggest new-onset criminal behavior in adults should prompt an assessment for frontal and anterior temporal brain disease and for dementing disorders.
Citation: Liljegren M, Naasan G, Temlett J, et al. Criminal behavior in frontotemporal dementia and Alzheimer disease. JAMA Neurol. 2015;72(3):295-300. doi: 10.1001/jamaneurol.2014.3781.