DMI-measured defenses and HIV-related risk behaviors in i.v. compared to non-i.v. substance abusers.

The Defense Mechanism Inventory (DMI) and The Risk Behavior Inventory (RBI) were administered to substance abusers hospitalized on a drug detoxification service. The groups were categorized on the basis of self-reported IV versus non-IV substance abuse. Significant between-group differences were obtained on the DMI and RBI. The non-IV group responded less often than the IV group with the Turning Against Object (TAO) response option, resulting in higher scores when Turning Against Self (TAS), Reversal (REV), Principalization (PRN) and Projection (PRO) were summed into a single score. Significant within-group differences were obtained for DMI response levels and defenses. Both groups relied less on TAO at the thought level and more on PRN and REV as primary defenses. The IV group reported twice as many risk behaviors as the non-IV group and risked HIV exposure through needle use and sexual transmission modes. Consideration was given to the role of principalization and denial within the addicted individual's defense structure and the relationship of these defenses to HIV-related risk behavior.