Comparison of million personality profiles of chronic residential substance abusers and a general outpatient population.

Several theories and studies have suggested that particular personality disorders or psychiatric symptoms should be associated with substance abuse. The current study was done to clarify these relationships by comparing scale profiles on the Millon Clinical Multiaxial Inventory obtained by 144 inpatient residentially treated substance-abuse clients and 1000 general clinical outpatient clients in psychotherapy. A surprisingly large number of significant differences were noted. Substance-abuse clients displayed relative elevations on scales for Alcohol and Drug Abuse, Hypomania, Antisocialism, Narcissism, Schizoidism, Paranoia, Psychotic Thinking, and Psychotic Delusions. General clinical outpatients showed relative elevations on Anxiety, Somatoform, Dysthymia, Borderline, and Compulsive scales. Some possible meanings of these findings were explored and suggestions for research given.