Trajectories of Alcohol‐Induced Blackouts in Adolescence: Early Risk Factors and Alcohol Use Disorder Outcomes in Early Adulthood
Abstract
Background and aims
Experience of alcohol‐induced memory blackouts in adolescence may be an important risk factor for later harms. This longitudinal study (i) modelled trajectories of alcohol‐related blackouts throughout adolescence, (ii) explored early‐adolescent predictors of blackout trajectories and (iii) examined the association between blackout trajectories and alcohol use disorder (AUD) symptoms.
Design
Longitudinal study in which data from six annual surveys of a longitudinal cohort of Australian adolescents were used to model latent class growth trajectories of blackouts, adjusting for alcohol consumption frequency and typical quantity. Regression models were used to determine whether parent, child and peer factors at baseline (mean age = 12.9) predicted profiles of blackout trajectory membership and whether blackout trajectories predicted meeting criteria for AUD in early adulthood (mean age = 19.8).
Setting and participants
Australian adolescents (n = 1821; mean age = 13.9–18.8 years).
Measurements
Alcohol‐related blackouts, alcohol consumption frequency, typical consumption quantity and DSM‐5 AUD in early adulthood were all self‐reported.
Findings
The research identified a three‐class solution: delayed alcohol initiation, rare blackouts (n = 701; 38.5%); early initiation, rare blackouts (n = 869; 47.7%); and early initiation, increasing blackouts (n = 251; 13.8%). Female sex was associated with increased risk of early initiation, increasing blackouts relative to delayed initiation, rare blackouts [relative risk ratio (RRR) = 3.90; 99.5% confidence interval (CI) = 1.96, 7.76] and relative to early initiation, rare blackouts (RRR = 2.89; 99.5% CI = 1.42, 5.87). Early initiation, rare blackouts [odds ratio (OR) = 1.96; 99.5% CI = 1.17, 3.29] and early initiation, increasing blackouts (OR = 4.93; 99.5% CI = 2.32, 10.48) were each associated with increased odds of meeting criteria for AUD in early adulthood relative to delayed initiation, rare blackouts. Early initiation, increasing blackouts was associated with increased odds of meeting criteria for AUD in early adulthood relative to early initiation, rare blackouts (OR = 2.51; 99.5% CI = 1.18, 5.38).
Conclusions
Females in Australia appear to be at higher risk of adolescent alcohol‐related blackouts independent of alcohol consumption levels and age of initiation. Alcohol‐related blackouts may be associated with later alcohol use disorder.
Research in Context
As the conversation reports, this study found that nearly one in ten 14 year olds and 48% 19 year olds who consumed alcohol had blackouts.
Furthermore, 14% of the adolescents had more and more blackouts as they aged. They were 2.5 times more likely to develop severe alcohol problems including alcohol abuse and dependence in early adulthood.
A blackout is when alcohol interferes with the brain’s ability to form long-term memories. This usually happens at about 0.15 or higher blood alcohol concentration level. The memories tend to be spotty or sometimes people can completely forget everything in a blackout experience.
Young people are specifically at higher risk from being affected by harm caused by alcohol products since their brains are still developing till about 25 years of age. Alcohol induced blackouts can lead to other issues for young people such as engaging in risky activities like, having unprotected sex, and other behaviour that can lead to injury.
Teachers and parents have an important role in ensuring that young people are protected from harm caused by alcohol products by making them aware about these issues.
