Daily relations among affect, urge, targeted naltrexone, and alcohol use in young adults.

Heavy drinking among young adults is a serious public health problem. Naltrexone, an opioid antagonist, has been shown to reduce drinking in young adults compared to placebo and can be taken on a targeted (i.e., as needed) basis. Understanding risk factors for drinking and naltrexone effects within-person in young adults may help to optimize the use of targeted naltrexone. The current study was a secondary analysis of daily diary data from 127 (n = 40 female) young adults (age 18-25) enrolled in a double-blind clinical trial of daily (25 mg) plus targeted (25 mg) naltrexone versus placebo. Hierarchical linear models were used to examine the effects of daily affect, urge, and taking targeted medication on same-day risk of drinking to intoxication (defined as estimated blood-alcohol-concentration, BAC ≥ .08 g%). Results indicated urge significantly mediated within-person positive affect-drinking relations on a daily level. Specifically, positive affect was associated with greater urge to drink, which in turn was associated with greater odds of BAC ≥ .08 g%. Furthermore, days of greater positive affect and urge were associated with taking a targeted dose of medication, which reduced the likelihood of intoxication by nearly 23% in the naltrexone group compared to placebo. Gender and family history of alcohol dependence were examined as moderators of these daily level effects. These results provide further evidence of naltrexone's ability to reduce alcohol consumption in young adults and identify potential within-person risk processes related to heavy drinking that could inform alcohol-related interventions for this population. (PsycINFO Database Record