Delinquent boys at increased risk of premature death and disability by middle age

The UK study, published in the December issue of the Journal of Public Health, is the first to examine how a wide range of early antisocial behaviours, as well as parental factors, affect various health outcomes 40 years later.

The study found that among boys who engaged at age 10 in antisocial behaviour such as regularly skipping school or being rated troublesome or dishonest by teachers and parents, and who then went on to be convicted of a crime by the age of 18, 16.3% (1 in 6) had died or become disabled by the age of 48. That compared with 2.6% (1 in 40) of the boys from the same lower socioeconomic South London neighbourhood who were not delinquent or offenders -- an almost seven-fold difference.

"We were surprised to see such a strong link between these early influences and premature death and this indicates that things that happen in families at age 8-10 are part of a progression towards dying prematurely," said the study's leader, Professor Jonathan Shepherd, Director of the Violence and Society Research Group at Cardiff University in Wales. "It was also surprising that the increase was not limited to substance abuse or other mental health problems known to be linked with an antisocial lifestyle, but included premature death and disability from a wide variety of chronic illnesses such as heart disease, stroke, respiratory disease and cancer."

"At this point, we don't know exactly why delinquency increases the risk of premature death and disability in middle age, but it seems that impulsivity -- or lack of self-control -- in childhood and adolescence was a common underlying theme. It may be that the stresses and strains of an antisocial lifestyle and having to deal with all the crises that could have been avoided with more self-control takes their toll. It fits with the biological evidence of the effects of chronic stress on illness." Professor Shepherd said.

The research is the latest update of a long-running study called the Cambridge Study in Delinquent Development that started following 411 boys at the age of eight or nine to investigate the influences on, evolution and long-term consequences of juvenile delinquency. The researchers interviewed the children, parents and teachers and verified criminal records to collect information on antisocial behaviour patterns, family dynamics and health status at various stages of life. The study started in 1961 and follow-up investigations were performed at ages 16-18, 27-32 and 43-48. By the time of the latest follow-up, 389 of the men were still in the study.

A total of 17 men had died by the age of 48 and 17 of the remaining 365 men followed had become disabled. Of 21 potentially important influences, six were significantly associated with premature death and disability, the researchers found.

Antisocial behaviour at age 10 was linked to a more than threefold chance of dying or becoming disabled by 48 (odds ratio: 3.5), early death or disability was also at least three times more likely in boys who had been convicted of a crime between the ages of 10 and 18 (odds ratio 3.0), in those convicted between the age of 10 and 40 (odds ratio: 3.5) and in those who at age 10 had a convicted parent, were separated from a parent or had poor parental supervision (odds ratio: 3.2). Impulsivity -- or lack of self-control -- at age 18 was associated with double the risk of death and disability by age 48 (odds ratio: 2.1). At age 32, self-reported criminal activity not picked up by the police, such as burglary, shoplifting, car theft, violence or vandalism, more than quadrupled the risk of death and disability by age 48 (odds ratio: 4.3).

"These findings indicate that by intervening in the development of delinquency we may be able to achieve more than a reduction in the likelihood of later offending, which is currently the goal of such interventions," Professor Shepherd said. "We should focus on improving parenting and tackling impulsivity in the early years, which may well improve long-term health, reduce costs to the health service and save lives."