Criminal minds in dementia: A systematic review and quantitative meta-analysis.

Introduction: Subjects with dementia might exhibit criminal risk behavior (CB), even in early disease stages.

Methods: This systematic review and quantitative meta-analysis investigated CB prevalence across all neurodegenerative syndromes according to PRISMA criteria and preregistered in PROSPERO. Mean frequencies and odds ratios were calculated and compared.

Results: Finally, the meta-analysis included 14 studies with 236,360 persons. Studies originated from different countries, with largest contributing country being the U.S.A., followed by Scandinavian countries, i.e., Sweden and Finland, and additionally Germany and Japan. All quantitative analyses revealed a very consistent picture: CB prevalence was highest in behavioral variant frontotemporal dementia ( >50%), followed by semantic variant primary progressive aphasia (40%), but rather low in vascular dementia and Huntington's disease (15%), Alzheimer's disease (10%), lowest in Parkinsonian syndromes ( <10%). The systematic literature review revealed that CB prevalence is more frequent in early disease course than in the general population, but declines thereafter below population levels. Men are overrepresented.

Discussion: CB is a common symptom in dementia, most pronounced in frontotemporal dementia. CB committed for the first time at mid-age could be an indicator of incident dementia, requiring earliest diagnosis and therapy. As present studies show a wide variability in assessment methods and cohorts investigated, and had been conducted in a minority of countries world-wide, large prospective international studies are warranted that systematically apply homogeneous methods and standardized questionnaires in assessing criminal risk behavior in different dementia syndromes.