Aims: Using Cloninger's model of personality, we aimed to specify the relative influence of the more biologically determined variables, temperament and character and more environmentally driven influence, childhood adversity in the development of addiction; and to compare patterns found among alcoholics with those found among drug addicts.
Methods: We studied a group of prisoners, at a high risk of substance abuse and past history of childhood adversity. Using a stratified random strategy we selected (i) 23 prisons among the different types of prison in France, (ii) 998 prisoners. Each prisoner was assessed by two psychiatrists--one junior, using a structured interview (MINI 5 plus), and one senior, completing the procedure with an open clinical interview. At the end of the interview the clinicians met and agreed on a list of diagnoses. Cloninger's Temperament and Character Inventory was used to measure personality. Structural equations models, which have been advocated to disentangle the respective influence of complex risk factors, were used.
Results: The "novelty seeking" temperament was a crucial vulnerability factor, for both alcoholics and drug addicts, in the same proportion. Character and childhood adversity played a significant part only in the development of drug abuse.
Conclusions: In a prison population, a common biological loaded factor, novelty seeking is found both at the core of alcohol- and drug-related disorder whereas environmentally loaded factors play a greater role in drug problems.