Alcohol misuse is common among adolescents. A recent survey found that approximately 2.4% of high school students in Japan  engage in binge drinking, which is lower than the data from other countries, including the United States (14.4% of 12th graders ) and Europe (35.0% of adolescents aged 16 years ). Although the prevalence of binge drinking in Japan is low when compared internationally, we should not make light of this problem because youth binge drinking increases the risk of alcohol-related disorders (including intoxication), accidents, fatal injuries, and chronic illness . Binge drinking also increases the risk of both acute and long-term negative consequences (e.g., injuries and alcohol disorders) , essentially, effecting further risk behaviors such as illegal substance use and sexual and violent behaviors [6,7,8]. Japanese culture includes a deep-rooted phenomenon similar to alcohol chugging. Often observed in society and media advertisements , it relates to risky heavy drinking, promoting positive perceptions and attitudes about alcohol consumption, and potentially affecting children’s beliefs and behaviors toward alcohol consumption. In fact, heavy underage and college drinking have been reported recently [10, 11], making it essential to raise awareness of the dangers of binge drinking and understanding and addressing the environmental factors surrounding adolescents, including the person themselves, at an early stage.
Emerging health research suggests that alcohol use is determined by multidimensional (including biological, psychological, and sociocultural) factors . Genetic variants affect the risk of alcohol misuse. Candidate genes related to alcohol dependence can be categorized into three groups: those related to (a) alcohol metabolism, (b) the stress response system, and (c) behavioral disinhibition [13, 14]. With respect to alcohol metabolism, alcohol dehydrogenase and aldehyde dehydrogenase are known to have a protective influence against excessive drinking and alcohol dependence . Regarding the stress response system, the initiation and retention of binge drinking behavior and alcohol dependence are related through dysregulated activation of the brain stress system by corticotropin-releasing hormones [16, 17]. Behavioral disinhibition, defined as the inability to inhibit socially restricted actions, including alcohol and other substance abuse, is related to the serotonin and dopamine pathways [18, 19]. Previous studies have associated polymorphisms of tryptophan hydroxylase, serotonin transporter and serotonin receptor genes in the serotonergic system, polymorphisms on dopamine receptors, dopamine β-hydroxylase, and tyrosine hydroxylase with risks of binge drinking and alcohol dependence [14, 20,21,22].
Psychological traits related to cognitive and emotional susceptibility to substance abuse are also crucial factors for the initiation and development of adolescent substance abuse . Among these, impulsivity and sensation seeking have received the most attention owing to their influence on risky behaviors (including drinking alcohol) [24, 25] with high levels being especially influential . Adolescents, in particular, may be more sensitive to alcohol’s reward and stimulant effects , but less so to its sedative effects . Several studies imply that neural changes during adolescence may temporarily increase sensitivity to certain effects (e.g., reward) of alcohol, promoting consumption during a drinking episode. It may also decrease sensitivity to other effects (e.g., sedative effects) that may help to limit drinking during an episode .
Regarding sociocultural factors, etiological mechanisms representing multiple systems (including family, peers, and community) interact across development to influence binge drinking tendencies . Here, family plays an essential role. Not only does parental drinking have a crucial influence on children, but studies [31, 32] show that disrupted family relationships (including parental separation or divorce) and parental intactness are associated with binge drinking. Furthermore, parental control and support are essential in preventing adolescents from engaging in risky drinking behaviors , since low warmth and low parental monitoring regarding their child’s alcohol use are associated with higher adolescent binge drinking prevalence . Importantly, binge drinking occurs where there is no parental supervision, such as someone else’s home . During high school, an adolescent’s social context shifts from family to peers. Binge drinking may be facilitated by the presence of peers and peer selection [36, 37]. Community factors include the neighborhood and school environment. A supportive school environment (e.g., incorporating alcohol prevention into the curriculum) is associated with reduced adolescent binge drinking independent of individual, family, and peer risk factors .
Recent studies have focused on the influence of alcohol use on others, including the potential impact of parental drinking on children, especially adolescent alcohol misuse. Whereas most studies focused on alcoholics and parents who had problems with alcohol , some recent ones included normative drinking patterns to analyze their influence on alcohol misuse among children in general. Results revealed that parental drinking habits affect early-onset drinking in children  and increase the risk of adolescent alcohol misuse and intoxication [41, 42]. Domestically, higher scores on the Children of Alcoholics Screening Test in high school and college students  reflect frequent drinking among parents.
Parental alcohol use increases the intensity of alcohol consumption in late adolescent life [44, 45]. Whereas heavy (and moderate frequency) drinking predicts larger amounts of alcohol consumption throughout adolescence , the frequency promotes the development of a risky trajectory in adolescent alcohol use . One study reports the predictive effects of paternal drinking frequency and volume on binge drinking among younger adolescents . Some studies identify research gaps in examining associations between parental drinking and child drinking [39, 42]. Research has mostly focused on addressing the association between parental drinking and habitual (chronic risk) adolescent drinking, but little is known about its association with adolescent binge drinking (an acute risk).
Similarly, the effects of parental drinking according to gender differences remain unclear. The study that revealed that paternal drinking frequency and intensity predicted excessive adolescent drinking for younger adolescents, also conceded that higher overall alcohol consumption rates may have influenced the results reflecting the father’s dominant influence . In contrast, many studies have reported the dominant effects of maternal drinking on adolescent alcohol misuse (although fewer reports exist on child binge drinking resulting from the mother’s drinking). For instance, only maternal drinking in two-parent families was significantly associated with adolescent drinking , with adolescents drinking more often when maternal drinking exceeded paternal drinking [47, 50].
Women are more susceptible to alcohol-related problems than men, their blood alcohol concentration tends to increase rapidly, and apart from potentially causing fetal alcohol syndrome (from drinking during pregnancy) , their problematic drinking behaviors may negatively influence their parenting. That is because mothers (typically) provide much of the child care  and better overall supervision, establishing stronger affective and interpersonal bonds with their children  compared to fathers, thus, those with drinking habits may exhibit an approving attitude toward their child’s alcohol use  and their alcohol consumption recommendations (to the child) may be a risk factor . Therefore, we predict that maternal drinking may influence binge drinking among adolescents.
Another concern related to parental drinking, is how both parents’ drinking influences the risk of binge drinking among adolescents. Previous studies have found that both the mother’s and father’s drinking increased the risk of adolescent drinking , and both parents using alcohol, significantly predicted adolescent alcohol misuse [57, 58]. In particular, heavy drinking by both parents predicted an earlier onset and a marked increase in adolescent drinking . However, the influence of both parents’ drinking habits on adolescent binge drinking is unrevealed, but considering existing evidence, the social learning theory may be applicable . Adolescents model their parents’ behavior , conceptualizing the process of parental drinking, which encourages adolescent drinking . A Japanese study showed that drinking in front of children had a greater influence than parents’ daily alcohol consumption. Nearly 80% of fathers and over 50% of the mothers in the surveyed sample drank in front of their children . The phenomenon of both parents in a family drinking may be associated with a more favorable attitude toward alcohol use (a longitudinal predictor of alcohol initiation and misuse later) , increased availability of alcoholic beverages, and the likelihood of drinking. In fact, most Japanese high school students who drink, find alcoholic beverages at home . Furthermore, parental permissiveness promotes higher binge drinking prevalence . Similarly, research implies that children of parents whose drinking places them in the middle consumption tier, are more exposed to negative outcomes. These include less attention and time to complete homework and irregular bedtime owing to their parent’s drinking . We predict that households where both parents drink heavily, may be more influential in adolescent binge drinking than where only one parent drinks.
Another challenge is whether parental composition (for example, father’s absence and mother’s absence) will affect child binge drinking. Most studies that examine the relationship between parental factors and adolescent drinking fail to separate the father’s and mother’s influence , report across parents, or lack information about the father’s drinking . Literature shows that adolescents from two-parent households are less prone to excessive alcohol use (including binging) than those from single-parent households , who are more likely to drink . Studies show that adolescents from non-intact families tend to drink more , disrupted families are related to child binge drinking , and adolescents engage in more frequent heavy drinking (including binging) when they do not live with both their biological parents .
Regarding the effects of gender differences (in single-parent households) on children’s drinking behaviors, alcohol use and delinquent behaviors among adolescents were higher in single-father homes than in single-mother homes, owing to lower levels of parental supervision observed in single-father homes . Research shows that children from single (mothers or fathers) parent homes were at higher risk of various behavioral problems (including alcohol use) than children from two-parent families. However, following control for confounders, only the single-father group’s results remained significant . Despite the latter and research showing that living with a single mother was associated with less heavy drinking than a single father , one study showed that poor mother-child communication in single-parent families increased hazardous drinking and drunkenness in adolescents . In this regard, it appears that parents’ control and support functions may differ according to gender. A Chinese survey showed: children in non-intact families reported their fathers exerted more paternal behavioral control (knowledge about their child, expectations, supervision, discipline, and demandingness) and their mothers more maternal psychological control (engaging their children’s feelings and thoughts) . Moderate amounts of family support and control would be effective for the socialization and development of sensible drinking in an individual , but parents lack in their parenting (including support and control) when drinking excessively , potentially causing deviant or excessive drinking behavior in adolescents.
Thus, adolescents from non-intact families are ostensibly associated with binge drinking. Also, since men and women have important but different roles affecting a child’s development, both living without a mother or a father, may hold binge drinking risks for adolescents. Next, we predict that for adolescents not living with either parent influences the prevalence of binge drinking. Related to this, past studies found that children living without both their biological parents engage more frequently in heavy drinking [32, 33, 69]. Importantly, many adolescents do not live with either parent owing to divorce or the death of a parent  which may affect their socialization process, since parents are the primary socialization agents during childhood and early adolescence and parents’ values and norms represent the first model for children. Furthermore, limited control and support in deficient families may cause deviant behavior in children . In particular, fragmented families increase the risk of frequent drinking and drunkenness among adolescents [31, 67], while adolescents without parents may have less protective (including parental control) support , monitoring, and parental warmth, which could have lowered the risk of binge drinking . Thus, we predict that adolescents who live with neither parent have experienced poor family functions, potentially causing delinquency and risky child behavior, including binge drinking.
Considering the above, we aimed to investigate the relationship between current parental drinking, according to parental composition, and binge drinking among high school students in Japan. Our hypothesis is that parental drinking (mother drinking and both parents drinking) and parental composition (father’s absence, mother’s absence, and neither parent present) would affect adolescent binge drinking. Particularly, we test whether the effects of father drinking and mother drinking separately, as well as the effects of father’s absence and mother’s absence separately, are associated with adolescent binge drinking behavior. Next, we test whether the combined effects of the (a) father and mother drinking and/or (b) father’s and mother’s absence, further influence adolescent binge drinking.