Interaction of age and sex as factors in understanding the anxiolytic effects of alcohol: Unasked questions limiting the understanding of a critical health issue

Abstract

Understanding the reasons why people consume alcohol is a critical health issue. Alcohol produces a variety of effects, including a reduction in stress or negative emotional states termed an anxiolytic effect. The anxiolytic effect of alcohol is an often-reported reason for why people begin consuming the drug. However, several factors concerning the stress-reducing effect of alcohol need to be investigated. For example, research has demonstrated that both age and sex are factors that impact alcohol's anxiolytic effect producing differential outcomes in aged female rats compared to aged male rats. In light of these findings, the current commentary highlights critical questions in need of research with the goal of better understanding how age and sex interact to influence the anxiolytic effect of alcohol. For example, the central nucleus of the amygdala has been identified as a critical brain region mediating the anxiolytic effect of drugs, but additional research is needed to understand how aging alters the neurological functioning of the central nucleus of the amygdala in both females and males. Furthermore, specific receptor isoforms, such as GABA_A receptor α2, have been shown to be critical for anxiolysis and understanding how aging and sex alter receptor isoform expression by brain region is needed. Finally, age and sex interact to alter allopregnanolone levels in brain and differential neurosteroid levels may mediate alcohol's unique anxiolytic effect in aged female rats compared to aged male rats. Given the increasing age of the population in most countries and the increasing alcohol consumption levels in females compared to males, investigating the interaction of sex and age on alcohol's anxiolytic effect has great promise to discover critical answers to what are currently unasked questions.