Subjective Response to Alcohol in Young Adults with Bipolar Disorder and Recent Alcohol Use: a Within-subject Randomized Placebo-controlled Alcohol Administration Study

Limited data exists on mechanisms contributing to elevated risk for alcohol use disorder (AUD) in bipolar disorder. Variation in subjective response to alcohol may relate to alcohol use and risk for AUD. This study used a randomized, placebo-controlled, cross-over, within-subjects design to investigate differences in subjective response to alcohol in 50 euthymic young adults (n = 24 with and n = 26 without bipolar disorder type I). Eighty-three percent of participants with bipolar disorder were medicated. Participants completed assessments of clinical history, alcohol expectancies, and recent alcohol use. Participants were dosed to a .08 g% breath alcohol concentration. The placebo condition occurred on a separate counter-balanced day. Subjective response to alcohol was investigated at similar time points during both conditions. Group, condition, and group-by-condition interactions were modeled, with condition and time of subjective response assessment as repeated within-subject variables, and subjective response to alcohol as the dependent variable. Greater stimulating effects and liking of alcohol were reported in people with bipolar disorder (group-by-condition interactions, p < .05) than healthy young adults. While young adults with bipolar disorder reported anticipating feeling less "mellow/relaxed" when drinking (p = .02), during both beverage conditions they reported feeling more "mellow/relaxed" (main effect of group, p = .006). Feeling more "mellow/relaxed" during the alcohol condition related to greater recent alcohol use in bipolar disorder (p = .001). Exploratory analyses suggested anticonvulsants and sedatives/antihistamines may relate to differences in subjective response to alcohol in bipolar disorder. Results suggest young adults with bipolar disorder may differ in alcohol expectancies and experience alcohol intoxication differently-with distinct relations between subjective response to alcohol and alcohol use-compared to healthy young adults.