No significant gender differences in driving-related skills of alcohol mixed with energy drinks in an experimental binge drinking episode

Olga Hladun^1,2Esther Papaseit Fontanet^1,2*Lourdes Poyatos¹Soraya Martín¹Ana Pilar Pérez- Acevedo¹Ana María Barriocanal¹Tatiana Bustos-Cardona¹Susana Malumbres¹Rafael De La Torre^3,4Klaus Langohr⁵Magi Farre^1,2Clara Pérez-Mañá^1,2*

• ¹Hospital Germans Trias i Pujol, Badalona, Spain
• ²Autonomous University of Barcelona, Barcelona, Catalonia, Spain
• ³Hospital del Mar Medical Research Institute (IMIM), Barcelona, Catalonia, Spain
• ⁴Pompeu Fabra University, Barcelona, Catalonia, Spain
• ⁵Universitat Politecnica de Catalunya, Barcelona, Catalonia, Spain

Consumption of alcohol mixed with energy drinks (AmED) is trendy among young people. It has been related to risk-taking behaviors like binge drinking and driving under alcohol influence. Previous data suggest that women are more sensitive to alcohol induced impairment. The aim of the study was to assess if women have higher acute effects (driving-related skills, subjective and physiological) after controlled administration of alcohol and energy drinks in an experimental binge-drinking episode. A randomized, cross-over, double-blind clinical trial was conducted in 28 healthy volunteers (14 men: 14 women) and with four treatment conditions: alcohol+energy drink (A/ED), alcohol+placebo of ED (A), placebo of alcohol+ED (ED) and both placebos (P). 70 g of alcohol in men and 55 g in women combined with 750 mL and 589 mL of ED, respectively, were administered in 80 minutes, mimicking a binge drinking episode. Driving-related skills (tracking test and psychomotor vigilance task), subjective effects (visual analog scales_VAS, biphasic alcohol effects scale_BAES and Addiction Research Center Inventory_ARCI), vital signs and alcohol and caffeine concentrations were measured along an 8-hours period. Peak alcohol concentrations in breath air were 0.46 mg/L in both genders, given that the dose was 21% lower in women. Similar peak blood caffeine concentrations in men and women were also observed (4500 ng/mL vs. 4635 ng/mL with A/ED, higher than with ED). Women reported higher drunkenness (effect size 45 mm; 95% CI: 5-85 mm), and alcohol-induced sedation than men (ARCI sedative subscale: effect size 12; 95% CI: 2-22), but no significant gender differences were found on driving-related skills. AmED slightly reduced alcohol effects on most subjective and psychomotor outcomes, but ED did not entirely offset alcohol effects, and no interaction was found among both beverages in both genders. Conclusions: After a binge drinking episode, women reported higher drunkenness and sedation than men. Our results support higher sensitivity of women to several subjective effects of alcohol, but further studies should be conducted to elucidate gender differences of AmED on driving performance. Clinicaltrials.gov NCT04616859.