Latent Trajectory Classes for Alcohol‐Related Blackouts from Age 15 to 19 in ALSPAC

Abstract

Background Alcohol-related blackouts (ARBs) are reported by ~50% of drinkers. While much is known about the prevalence of ARBs in young adults and their cross-sectional correlates, there are few prospective studies regarding their trajectories over time during mid-adolescence. This paper reports latent trajectory classes of alcohol-related blackouts between ages 15 and 19, along with predictors of those patterns. Methods Latent Class Growth Analysis (LCGA) was used to evaluate the pattern of occurrence of ARBs across four time points for 1402 drinking adolescents from the Avon Longitudinal Study of Parents and Children (ALSPAC). Multinomial regression analyses evaluated age 15 demography, substance-related items, externalizing characteristics, and estimated peer substance use as predictors of latent class membership. Results ARBs were reported at age 15 in 30% and at age 19 in 74% of these subjects. Four latent trajectory classes were identified: Class 1 (5.1%) reported no blackouts; for Class 2 (29.5%) ARBs rapidly increased with age; for Class 3 (44.9%) blackouts slowly increased; and for Class 4 (20.5%) ARBs were consistently reported. Using Class 2 (rapid increasers) as the reference, predictors of class membership included female sex, higher drinking quantities, smoking, externalizing characteristics, and estimated peer substance involvement (pseudo R2 =.22). Conclusions ARBs were common and repetitive in these young subjects, and predictors of their trajectories over time involved multiple domains representing diverse characteristics.

Alcohol-related blackouts across 55 weeks of college: Effects of European-American ethnicity, female sex, and low level of response to alcohol

“…Recently, the prevalence of ARBs has reached alarming rates, especially in females and individuals with early onset drinking (Marino and Fromme, 2015; Schuckit et al, 2015; White et al, 2015). The UCSD freshmen studied here are no exception to these trends as 43% of these students reported at least 1 ARB during the 55 weeks, including 48% in females and 35% in males.…”

“…These included the drinks required to produce any effect, slurred speech, unsteady gait, and unwanted falling asleep. The SRE has Cronbach alphas and repeat reliabilities >.88 (Ray et al, 2011; Schuckit et al, 2015, 1997). This retrospective self-report measure was used rather than alcohol challenges because the latter are too expensive and time consuming for use in a large population (Schuckit and Gold, 1988).…”

“…Lifetime risks for alcohol-related blackouts (ARBs) in many surveys is >50% among drinkers (Barnett et al, 2014; Schuckit et al, 2015; White et al, 2002). The high blood alcohol concentrations (BACs) involved (Goodwin, 1995; Perry et al, 2006) and the compromised cognitive processes inherent in ARBs (Silveri et al, 2014) increase risks for additional serious consequences, including accidents, unwanted sex, and exposure to other forms of violence (Hingson et al, 2016, Mundt and Zakletskaia, 2012; White et al, 2004).…”

“…The high blood alcohol concentrations (BACs) involved (Goodwin, 1995; Perry et al, 2006) and the compromised cognitive processes inherent in ARBs (Silveri et al, 2014) increase risks for additional serious consequences, including accidents, unwanted sex, and exposure to other forms of violence (Hingson et al, 2016, Mundt and Zakletskaia, 2012; White et al, 2004). In addition to BACs>.20g/dl needed for most blackouts, ARBs are also associated with European American [EA] ancestry, female sex, and several genetically-influenced phenotypes related to heavier drinking, including a low level of response (low LR) to alcohol, as described further below (Marino and Fromme, 2015, 2016; Schuckit et al, 2015, 2001; Wetherill and Fromme, 2016, 2009; White et al, 2015). However, the relationships among these characteristics and ARBs are complex and their potential interactions have not been adequately evaluated (Wetherill and Fromme, 2016).…”

“…One contributor to higher ARB rates in women (Marino and Fromme, 2015; Schuckit et al, 2015) may be their higher BACs per drink (Baraona et al, 2001; Rose and Grant, 2010). This reflects women’s likely lower body weight, less first pass metabolism of alcohol, and higher body fat with corresponding less body water per pound.…”