Antisocial behaviour over the life course among females and males treated for substance misuse

Aims: (1) To compare the prevalence of adverse outcomes in adulthood between a
clinic cohort and a matched sample from the general population; (2) To examine the
associations between adolescent antisocial behaviour and adverse outcomes in
adulthood; (3) To identify subgroups of male and female offenders with distinct
features of offending, and to examine the long-term continuity of offending in the
subgroups, and; (4) To identify long-term offending trajectories and examine the
relationship between these offending trajectories and concurrent problems in other
areas.
Method: Participants were part of a longitudinal study of adolescents who were treated
at a substance misuse clinic during two periods: 1968-1971 (Cohort 1; 1992
participants), and 1980-1984 (Cohort 2; 1576 participants). The same number of
individuals were randomly selected from the general population and matched to the
clinic cohorts. Baseline data was extracted from archival data, and participants were
followed to 2002 through multiple national registers.
Results: Individuals from cohort 1 were at increased risk of several adverse outcomes
in adult life when compared to the matched sample. Additionally, adolescent antisocial
behaviour increased the risk of adversity in multiple domains up to age 50 in cohort 1.
Several subgroups of offenders could be identified in adolescence and again in
adulthood in cohort 1, and considerable continuity in offending was shown among
several subgroups. Individuals with high levels of violent and non-violent offending in
adulthood also demonstrated high levels of substance-related crimes. Multiple longterm
offending trajectories were identified in cohort 2 and in the matched sample.
Cohort 2 showed less desistance in offending than the matched sample, and trajectories
with the highest offending rates displayed the highest rates of concurrent problems.
Both sex differences and similarities were demonstrated in all studies; larger
differences in outcomes were found between women in cohort 1 and women in the
matched sample, than between their male counterparts. In cohort 1, males demonstrated
higher offending levels and more offending diversity, and specific subgroups and
trajectories were identified among the males that were not replicated among the
females. Conversely, adolescent antisocial behaviour was associated with adult
adversity equally in females and males in cohort 1, and no sex differences were found
in the continuity of offending, or in the relationship between substance-related crimes
and other crimes in the same cohort. Both genders also demonstrated similarities in the
associations between concurrent problems and offending trajectories in cohort 2.
Conclusions: An increased risk of both homotypic and heterotypic continuity of
problems through 30 years of adult life was demonstrated among individuals treated for
substance misuse as adolescents. This highlights the importance of assessing and
treating the multiplicity of problems to prevent continuation of current problems, and
the emergence of new ones. Treatment should also acknowledge heterogeneity and aim
to target specific needs, instead of accommodating a wide range of problems with the
same intervention strategy. The findings further suggest that intervention is equally
needed among girls who present antisocial behaviour in adolescence, as this is
predictive of adult adversity. Altogether, the findings point to the importance of early
and effective interventions to prevent further antisocial behaviour, and the problems
associated with it