Family alcohol use, rather than childhood trauma, is more likely to cause male alcohol use disorder: findings from a case-control study in northern China

The etiology of alcohol use disorder (AUD) is complex and results from a combination of biological factors as well as psychological and sociological factors. Among them, biological factors cover many aspects such as genes, individual metabolism, central reward system, and changes in neurotransmitters such as dopamine and γ-aminobutyric acid [1, 2]. Psychological and sociological factors include personality traits, childhood experiences, social culture, and many other aspects. In terms of personality traits, such as low levels of empathy [3], high novelty seeking [4], high levels of impulsivity [5], depressive and anxious temperament [6], as typical personality characteristics of AUD, not only increase the risk of AUD, but also have impacts on emotional state, craving, and relapsing. In terms of childhood experiences, childhood trauma has received a lot of attention as an important and relatively independent factor. The World Health Organization (WHO) defines childhood trauma as the actual or potential harm done by a person who is obligated to raise, supervise, or care for a child [7]. These harms can include physical, emotional, and sexual abuse; neglect; and deprivation. All such harms are sufficient to compromise children’s health, survival, growth, development, and dignity.

A study in China found that rates of emotional, physical, and sexual abuse as well as emotional neglect during childhood are higher among patients with alcohol dependence than in the general population [8]. Other studies found that childhood traumatic experiences are an important risk factor for alcohol use disorders [9‐11]. Studies by WHO and in eight Eastern European countries also found that emotional neglect in childhood trauma is significantly related to adolescent health-related risk behaviors such as alcohol abuse [12]. Alcohol abuse is 6–12 times more common among patients who suffered physical abuse in childhood than among those who did not [13]. Childhood trauma may lead to alcohol use disorder in adulthood through mechanisms based on post-traumatic stress or with the goal of “self-medication” [14‐17]. Under the influence of physical and mental post-traumatic symptoms, patients may become socially maladjusted, coping unproductively with negative events and suffering distortions in cognition and personality. This causes various problems for patients, who resort to psychoactive substances such as alcohol for short-term self-healing and relief of anxiety and depression [18‐21].

The family is the earliest and most important social environment for children’s growth experiences. The behavior of parents is commonly imitated by children [22]. Parental alcohol use may be a behavior imitated by the child. The parent’s attitudes and behaviors toward alcohol use may also be imitated by the child, which may play an important role in the development of alcohol use disorder. Therefore, how parents use alcohol may play a vital role in determining how children and adults use it, in addition to genetic factors [23]. The severity of parental alcohol use disorder affects the risk of alcohol use disorder in children, but how specific alcohol-related parental behaviors as well as other social and psychological factors may influence children’s behaviors toward alcohol has not been fully evaluated. Also unknown is whether these social and psychological factors are more important contributors to alcohol use disorder than childhood trauma. Many studies have found that parental alcohol use is a risk factor for childhood trauma [24‐26], but whether parental alcohol-related behaviors and attitudes in themselves can affect children’s drinking behavior is unclear.

Therefore, we conducted a study to evaluate and compare the impacts of family alcohol use and childhood traumatic experiences on the development of alcohol use disorder among Han Chinese men from northern China.

Through this study it was demonstrated that family alcohol use, which included parental drinking frequency, parental attitudes toward childhood drinking, being induced to drink as a child, age at first drink and at first drunkenness, may play a vital role in the occurrence of AUD. In fact, these factors may be stronger contributors to AUD than experience of trauma in childhood, education level or history of smoking.

In this study, we found that the ages at first drink and first drunkenness were significantly lower in Chinese men with alcohol use disorder than in healthy age-matched men. This may reflect the influence of early exposure to alcohol due to family alcohol use and childhood traumatic experiences. In particular, the father’s drinking frequency and whether he opposed drinking during the subjects’ childhood appeared to affect their risk of alcohol use disorder in adulthood. Premature exposure to drinking or even drunkenness may reflect parental neglect of children and tacit approval of drinking, which would also increase risk of alcohol use disorder.

Han Chinese in northern China are more traditional than other ethnic groups or than Han Chinese in the south of the country [32]. The status of men in their families is higher than that of females, and male drinking is more acceptable than in other ethnicities. This is closely related to the influence of traditional Chinese Confucianism and local cultural customs. Therefore, fathers’ drinking behavior and attitudes may influence children, especially sons, more strongly than mothers’ behavior and attitudes. Children’s understanding of how men “should” behave originates mostly with the father [33, 34]. Therefore, the more the father drinks per week, the more likely the son will develop an alcohol use disorder during adulthood. The proportion of healthy controls whose fathers opposed childhood alcohol consumption was higher than the proportion of patients, suggesting that fathers’ attitudes towards their children’s drinking is one of the factors that affect the risk of alcohol use disorder [35]. Many families in northern China often encourage their children to try drinking when they have dinner during major festivals, which is partly related to local customs and also often serves as a form of entertainment at the table. However, this behavior often lowers children’s vigilance toward alcohol use, and it promotes the perception that drinking can be an effective way to attract attention from relatives and friends. At the same time, the encouragement from relatives and friends serves as implicit consent to children’s drinking. In this way, the idea that drinking is a typical male behavior is solidified in children’s minds. In the present work, we found that induced drinking during childhood is one of the most important risk factors for alcohol use disorder among adult men. This suggests that, regardless of the purpose of induced drinking during childhood, it often leads to alcohol use disorder in adulthood. Indeed, a previous study in Australia found that parents’ providing alcohol to their children greatly increases the risk that the children will suffer alcohol use disorder and alcohol-related harm in adolescence [36].

We observed that the proportion of men with alcohol use disorder whose mothers opposed childhood alcohol consumption was much higher than the proportion of healthy men. This may be related to the higher frequency of fathers’ drinking among people with alcohol use disorder, which may elicit strong opposition from mothers as a way to protect their children. Discrepant attitudes between mother and father towards drinking in childhood may trigger cognitive conflict in the child about drinking. Boys may then tend to side with the “masculine” view, rendering them more vulnerable to alcohol use disorder [35].

Childhood trauma experiences were more frequent among our men with alcohol use disorder than among our healthy controls. Childhood traumatic experiences lead to brain dysfunction, which may involve changes in neuromorphology, neural pathways, and gene expression [37, 38]. Functional magnetic resonance imaging studies have shown that the activation of certain brain regions is more difficult in individuals who have experienced childhood trauma [39, 40], which can lead to abnormal functions in the central reward system [41]. Childhood traumatic experiences also directly trigger negative emotions such as self-denial, pessimism, and anxiety [42]. In order to avoid these negative emotions, individuals often resort to alcohol, tobacco, and other psychoactive substances, increasing the risk of alcohol use disorder.

Negative emotions arising from childhood trauma also lead to increased sensitivity and alertness to external stimuli. Excessive sensitivity and alertness can cause anxiety, impulsivity, and uncontrollable emotions, resulting in decreased self-control when using psychoactive substances. Moreover, the availability of alcohol makes drinking one of the most convenient and legal ways to relieve anxiety, reduce sensitivity and alertness, and feel less alone [42]. Indeed, abuse or neglect during childhood can lead to emotional and behavioral problems and increase the risk of mental illnesses during adulthood, including substance use disorders and schizophrenia [42‐46],

In contrast to these various risk factors, we observed that higher education level was a protective factor against alcohol use disorder in our sample. This may be because a higher education level improves cognition and control of alcohol use, reducing risk of its abuse [47, 48]. In general, higher education level in children is associated with higher parental education level and income, and more affluent families usually show more self-control in using alcohol [49] and may protect their children more from trauma [50]. The fathers and mothers in more affluent households are also more likely to share similar attitudes towards childhood drinking [49]. In this way, higher education level may directly and indirectly decrease risk of alcohol use disorder.

We found that a history of smoking was much more frequent among men with alcohol use disorder than among healthy men. This may reflect that tobacco is one of the most common and easily available, legal psychoactive substances, often used in conjunction with alcohol. In addition, a family’s positive attitude towards smoking is often similar to the family’s positive attitude towards the use of alcohol [51‐53]. Tobacco and alcohol use disorders may, in fact, be linked to similar genetic polymorphisms [54].

Our study presents several limitations, such as the small, mono-sex sample, sampling in northern China, and unmatched education level. Furthermore, we excluded comorbidity of other mental diseases, did not identify clearly the family history of mental illness or addiction diseases and did not take into account parenting styles or personality traits. Our work needs to be confirmed in a larger sample that takes into account a wider range of biological, social, and psychological factors. For example, parenting styles have been associated with alcohol-related problems in childhood [55], and personality traits can influence risk of alcohol use disorder [56].

Despite these limitations, our study provides evidence that family alcohol use may contribute more strongly than childhood trauma to alcohol use disorder in adult men. Our results may help guide family-based policies for prevention of alcohol use disorder.