Impact of substance use and other risk factor exposures on conviction rates by people with a psychotic illness and other mental disorders

PURPOSE

To examine the impact of substance use and other risk factors on conviction rates in people with a psychotic illness (PI) and other mental disorders (OMD) compared to those with no mental illness (NMI).

METHODS

This research is part of a longitudinal record-linked whole-population study of 467,945 children born in Western Australia (WA) between 1980 and 2001. This cohort was identified through linkages between the WA psychiatric case register, WA corrective services data and other state-wide registers. We assessed 184,147 individuals born during 1983-1991 to explore the impact of exposure to a variety of risk factors on conviction rates.

RESULTS

People with PI and OMD had higher conviction rates than those with NMI, with unadjusted incidence rate ratios (IRR) of 3.98 (95% CI 3.67-4.32) for PI and 3.18 (95% CI 3.03-3.34) for OMD. Adjusting for substance use reduced the rates by 60% in PI and 30% in OMD: IRRs 1.59 (95% CI 1.45-1.74) and 2.24 (2.12-2.37), respectively. Minimal change was seen when adjusting for other potential risk factors (including socio-demographics, victimisation and parental offending), with adjusted IRRs 1.58 (95% CI 1.43-1.74) for PI and 1.90 (95% CI 1.80-2.02) for OMD.

CONCLUSIONS

Our analysis shows people with a mental illness have higher rates of conviction than those with NMI. Substance use has a major impact on this rate. Results suggest the need for a greater investment in programs addressing the issue of comorbid substance use with a view to reduce the rate of convictions in this population.

The influence of parental offending on the continuity and discontinuity of children's internalizing and externalizing difficulties from early to middle childhood

PURPOSE

Although parental criminal offending is a recognized risk factor for conduct problems among offspring, its impact on the continuity and discontinuity of children's behavioural and emotional difficulties during the early development is less well known. We used data from a large, population-based record-linkage project to examine the relationship between parental offending and the continuity and discontinuity of children's conduct, attentional, and emotional difficulties from early to middle childhood while also considering the role of timing of the parental offending exposure.

METHOD

Data for 19,208 children and their parents were drawn from the New South Wales Child Development Study. Multinomial regression analyses tested associations between mother's and father's history and timing of any and violent offending, and patterns of continuity or discontinuity in offspring emotional, conduct, and attentional difficulties between ages 5 and 11 years.

RESULTS

Maternal and paternal offending each conferred a significantly increased risk of all the patterns of developmental difficulties, including those limited to age 5 only (remitting problems), to age 11 only (incident problems), and to difficulties present at both ages 5 and 11 years (persisting problems). Greatest odds were observed for persisting conduct problems. Paternal offending that continued through early and middle childhood had the greatest association with child difficulties, while the timing of maternal offending had a less prominent effect on child developmental difficulties.

CONCLUSION

Parental offending is a strong risk factor for early and pervasive behavioural and emotional problems in offspring, and may be a key indicator of high risk for later antisocial behaviour.