To Örebro University

Previous studies have shown that criminal and other externalizing behaviors are associated with several adverse outcomes, but very little is known about the impact of these behaviors beyond middle adulthood. Few studies have explored how a life-course background of criminal and externalizing behaviors influence aging and more specifically, whether it is associated with the onset and development of different neurodegenerative, mental, and physical health disorders when aging. The overarching aim of this dissertation is to advance the knowledge about the long-term influence that criminal and other externalizing behaviors along the lifespan may have on health and neurodegeneration while individuals age. This aim was explored throughout three studies: Study I, a systematic review and meta-analysis performed to investigate the prevalence of several mental and physical health problems of older offenders; Study II, a Swedish population-based register study which examined how the severity of the criminal background associated with dementia and mild cognitive impairment (MCI), and how several life-course factors influenced these associations and; Study III, a multi-generation cohort study investigating whether externalizing behaviors and dementia co-aggregate in families. The main findings suggest that older adults with criminal and externalizing behavioral backgrounds, and overall, those with a severe criminal history, exhibit an increased liability to develop physical and mental health problems as well as MCI and dementia when aging. This increased risk is influenced by life-course health and psychosocial problems as well as genetic and familial environmental factors. In general, findings from this thesis point towards a better understanding of the aging process of individuals with this background, and to further the scientific knowledge about the influence of life-course adverse behaviors on aging. This knowledge may promote the development of preventive and interventive strategies for individuals with a criminal and externalizing behavioral background.