Effects of alcohol on baseline startle and prepulse inhibition in young men at risk for alcoholism and/or anxiety disorders

Objective: This study examined the hypothesis that a decreased reaction to alcohol and a deficit in prepulse inhibition (PPI) of the startle reflex are characteristics of male offspring of alcoholics without comorbid anxiety disorder. Method: Male offspring (N = 51) with a parental history of (1) alcoholism only, (2) anxiety disorder only, (3) alcoholism and anxiety disorder, and (4) no psychiatric disorder participated in an experiment examining the effects of alcohol on the acoustic startle reflex and on PPI. The experiment was carried out in two sessions in which subjects received an alcoholic beverage and placebo beverage on alternate days. Results: The magnitude of startle was reduced by alcohol in each group. However, the degree of reduction was less in the offspring of alcoholics only compared to the other groups. In addition, PPI was reduced in the offspring of alcoholics only compared to the offspring of parents with no psychiatric disorder. Conclusions: A reduced reactivity to the effect of alcohol and a deficit in PPI might constitute vulnerability markers for alcoholism, but only in offspring of alcoholics without comorbid anxiety disorder.