Neurodegenerative diseases 'may increase risk for criminal behavior'
From：Medical News Today View：541 Date：2015-01-07
The study, published online in JAMA Neurology, also states that criminal acts such as theft, traffic violations, and public urination are also more likely to be early manifestations of such disorders.
Neurodegenerative diseases can cause dementia - a progressive decline in cognitive functioning that can interfere heavily with daily routines and social interactions.
In particular, neurodegenerative diseases such as Alzheimer's disease and behavioral variant of frontotemporal dementia (bvFTD) can prevent the areas of the brain involved with decision making, emotional processing, judgment, self-awareness, sexual behavior and violence from functioning properly.
The researchers note that dementia can lead to people with no history of antisocial activities exhibiting behavior that is antisocial and often could be classified as criminal by law and society. Despite this pre-existing association, they report that few studies have attempted to systematically assess antisocial behavior among people with dementing neurodegenerative disorders.
A review of medical records
For the study, researchers from Lund University, Sweden, and the University of California, San Francisco (UCSF), reviewed the medical records of 2,397 patients. The patients all attended the UCSF Memory and Aging Center between 1999 and 2012.
The following diagnosed neurodegenerative disorders among others were observed in the assessed patients:
- Alzheimer's disease - 545 patients
- bvFTD - 171 patients
- Semantic variant of primary progressive aphasia (svPPA) - 89 patients
- Huntington disease - 30 patients.
Frequency of criminal behavior among the patients was assessed by screening for specific keywords identifying criminal behavior among 13,477 patient notes.
Criminal behavior was defined by the study as "acts that violate the law as well as those that deviate from social decorum and could potentially lead to legal ramifications," with keywords decided upon by two neurologists: Dr. Georges Naasan and Dr. David C. Perry.
The review showed a history of criminal behavior in 204 (8.5%) of the patients that emerged during their illnesses. In particular, the following percentages of patients were found to have documented criminal behaviors:
- Alzheimer's disease - 7.7%
- bvFTD - 37.4%
- svPPA - 27%
- Huntington disease - 20%.
Types of criminal behavior observed most frequently varied between diseases and patient gender. Patients diagnosed with bvFTD were most likely to have acts of theft, traffic violations, sexual advances, trespassing and public urination documented. In general, traffic violations were most frequently committed by Alzheimer's disease patients, which were commonly related to memory loss.
Every case of public urination involved male patients, and men were significantly more likely to make inappropriate sexual advances, with the likelihood of 15.2% (men) compared with 5.1% (women).