Impulsivity has been associated with alcohol dependence, but impulsivity in alcohol-dependent subjects has not been well characterized.

Using a variety of laboratory measures of impulsivity, we assessed whether alcohol-dependent patients (ADP) were more impulsive than control subjects, and the role of Cluster-B personality disorders in impulsivity measurements.

A cross-sectional patient survey with a community comparison group. Diagnoses were made using the Structured Interview for DSM-IV. Sustained attention and rapid-response impulsivity were assessed using the continuous performance test (CPT). Inhibitory control was measured by the stop-signal task (SST). Ability to delay reward task was assessed using differential reinforcement for low-rate responding (DRLR).

A final sample of 253 males with alcohol-dependence recruited from two alcoholism treatment centres was compared with a matched non-substance-abusing comparison group (n=96).

Patients with alcohol dependence were more impulsive across all behavioural tasks. Alcohol-dependent subjects without personality disorders showed lower efficiency in DRLR than control subjects. Patients with Cluster-B personality disorder performed worse in inhibitory control, but subjects with borderline personality disorder in particular demonstrated increased rates of omission and commission errors in CPT. Inability to delay gratification was associated with antisocial personality disorder.

Our findings support the suggestion of two paradigms in alcohol dependence. The first, based on inability to delay gratification, might be a vulnerability marker for alcohol dependence. The second was related to inhibitory control, and might be specific for antisocial and borderline personality disorders.