Younger substance users show more psychosis and violence

264 patients followed for six months in Spain, comparing those whose use began early to longer-term older users.

Does the age at which someone’s substance use takes hold change how the illness looks? This six-month study from Spain suggests it does, in ways that matter for treatment. Researchers followed 264 patients with substance use disorder at an addiction treatment unit, splitting them into two groups: those with “prolonged” use histories (aged 55 or older, or 25-plus years of use) and those with shorter trajectories (younger and fewer years of use). Everyone completed structured interviews and validated measures of quality of life, impulsivity, autistic traits, addiction severity, psychotic symptoms, and violence. The younger group stood out for a heavier psychiatric burden: significantly more auditory and visual hallucinations and persecutory (paranoid) delusions at the start, along with more violence-related behavior. Over the six months, both groups reduced physical aggression in some contexts, though verbal aggression (insults and threats) rose. Notably, screening positive for ADHD, autistic traits, or high impulsivity didn’t predict who stayed in treatment; instead, poorer physical functioning predicted dropping out among longer-term users. The takeaway is a case for age-sensitive addiction care: younger people arriving with substance problems may carry a sharper load of psychosis and violence risk that deserves direct attention, while older, long-term users may need more support around physical health to stay engaged.