Considering the increasing prevalence of psychological problems among Chinese college students and the possible impacts of ACEs on depression and anxiety in adulthood, this study identified three specific patterns of ACE exposure among Chinese college students, including “low ACEs”, “high domestic violence and childhood abuse” and “family dysfunction but low childhood abuse”, and examined their associations with depression and anxiety, thus proposing targeted suggestions to promote the mental health of college students.
Despite of the fact that the incidence of depressive symptoms and anxiety of Chinese college students in this study were higher than those in the previous research [3, 4], the results were consistent with the escalating trend of mental health problems among these group of people [3]. The increasing risk of these mental conditions among them may attribute to the influence of COVID-19, such as having relatives or friends being infected, massive media exposure [42], perceived COVID-19-related strain [43], lockdown and social isolation [44]. Therefore, due to the high incidence of depression and anxiety among college students in China, special attention should be paid to it and targeted measures should be taken to improve their mental health.
Similar to the previous studies [18, 25], this study also divided the participants into a low-exposure class and other classes with specific features. LCA identified three heterogeneous classes of Chinese college students distinguished by different patterns of ACE exposure, namely “low ACEs”, “high domestic violence and childhood abuse” and “family dysfunction but low childhood abuse”. Among these classes, the “low ACEs” class was the largest group (63.1%), which was consistent with the results in the study on ACE patterns among college students in Xiamen, China [18].
A specific class was marked by witnessing household violence and suffering from childhood abuse and neglect (mainly emotional abuse, emotional neglect and physical abuse), with low exposure to household dysfunction, accounting for 16.8% of the participants. The proportion of college students endorsing this ACE pattern was similar to that reported in the survey of ACE patterns in 1346 university students in East Asia [25], where household violence (20.58%) was the second largest class, with the highest probabilities of endorsing exposures to both physical and emotional abuse and witnessing domestic violence, and with relatively low probabilities of suffering from other types of ACEs. Such results indicate that growing up in a violent but well-functioning household is still relatively common among children in China. It is possible that the specific values and beliefs in the Chinese culture, such as “spare the rod and spoil the child” and “under the stick comes filial piety”, may be rooted in the heart of Chinese parents and passed down from generation to generation. Additionally, domestic violence is usually categorized as “a family affair” in China, which means that it is considered as a private issue within the family, rather than anyone else’s business. However, this is a critical barrier to conducting research on domestic violence, which prevents the public and policymakers in China from understanding the prevalence, severity, and impacts of it [45]. In such cultural context, the endorsement of corporal punishment as a form of education and the normalization of family violence, may increase the risk of suffering from domestic violence both directly and indirectly among Chinese children [25].
Another specific ACE exposure pattern was characterized by a high likelihood of living in a dysfunctional family, experiencing emotional neglect and witnessing domestic violence, but a low likelihood of suffering from physical and emotional abuse. This was the second largest class in this study. However, the previous study reported only a very small group of people who were classified as household dysfunction, suggesting relatively rare non-violence-based ACEs in the conservative culture in Asia [25]. Thus, the difference in the results suggests that childhood household dysfunction may become an increasingly common issue in China [46] and that it is worth exploring the specific impact of household dysfunction on Chinese children. Furthermore, the result of such classification is consistent with the previous study indicating the frequent occurrence of emotional neglect and witnessing interparental violence, instead of childhood abuse, in families with separation-associated parental conflict [47], indicating a particular need for special attention to the mental health development of children living in dysfunctional families.
Compared with the “low ACEs” class, the “high domestic violence and childhood abuse” class showed a higher risk of depression in adulthood, indicating that experiencing abuse or violence in childhood, both directly and indirectly, was closely associated with mental health problems later in life. In terms of experiencing abuse directly, the finding was correspondent with the study demonstrating the positive relationship between physical abuse during childhood and depression in adulthood, which was mediated by allostatic load [48]. That is to say, childhood abuse may cause chronic or inappropriate adaptation to the repeated or prolonged exposure to stress, thus causing depression in adulthood. As for suffering from violence indirectly, the result was consistent with the study indicating that witnessing domestic violence had negative effects on the psychological functioning far beyond childhood, with intimate partner violence in adulthood as the mediator [49]. In other words, individuals who have witnessed intimate partner violence between their parents may consider it as an acceptable means of resolving conflict between partners, and might then tolerate it in the intimate relationships when they grow up, thus leading to a higher risk of depression. Therefore, education on how to effectively improve mental resilience and properly manage intimate relationships is needed for college students, especially those who were raised by conflictive or abusive parents.
Similar association was also found between the “high domestic violence and childhood abuse” class and a higher risk of anxiety in adulthood, compared with the “low ACEs” class. Previously, corporal punishment from both mothers and fathers were reported to be positively correlated with child anxiety in China, which is consistent with the result in this study [50]. Considering the possible explanation, the resulting insecure attachment to parents may reduce the emotional security in children, probably making them more easy to worry that something negative will happen to them, while without the ability to control it [50]. Additionally, the previous study has shown that being raised by conflictive or abusive parents was strongly associated with various mental disorders, especially internalizing anxiety disorders [51], which was in line with the evidence showing domestic violence and childhood abuse as the two most important risk factors for anxiety disorders [52], further supporting that certain co-occurrence of ACEs were critical for specific mental problems [53].
Meanwhile, the risks of depression and anxiety were also higher in the “family dysfunction but low childhood abuse” class than those in the “low ACE” class, but this result was different from that in the previous study among college students in East Asia [25], which reported no difference between the “low ACEs” class and the “household dysfunction” class. However, in a more recent study, it was reported that parental loss (including parental death, divorce, alcoholism, crime, drug addiction, bedridden, and lack of parental raising) during 7–12 years was strongly associated with depression in adulthood in Southwest China [54]. Similar results were also reported in studies in America [55] and in rural Vietnam [56]. It is possible that children living in a dysfunctional family may develop an exaggerated sensitivity to physical, emotional and social stressors (like harsh words, slamming doors, neglect and lack of affection), resulting in negative emotions, low self-worth, anxiety and other mental health problems [57]. Without the support from a significant other or sufficient psychological resilience, such exposure may cause deeper insecurity and continuously uncomfortable emotional states in the future. Therefore, family dysfunction probably played an increasingly important role in the psychological development in children, and special attention should be paid to the emotional state and mental health development of children with family dysfunction, but its specific effects on mental health remain to be further discussed.
The results also revealed that the “high domestic violence and childhood abuse” class were nearly twice more likely to report depression than the “family dysfunction but low childhood abuse” class. This finding supports previous research demonstrating that certain types of ACEs may lead to more adverse mental health outcomes than other ACEs [25, 58]. Specifically, the result suggests that, compared with household dysfunction, domestic abuse in childhood probably had a stronger association with the lower threshold for feeling pressure or depression and the worse ability of psychological adjustment in adulthood. It was consistent with the previous study showing stronger association between the “conflict-abuse” class and the overall worse mental health, compared with the “separation” class, which was found to be more closely connected with higher risk of externalizing neurodevelopmental disorders and substance use disorders [53]. This suggests that different patterns of ACE exposure may lead to diverse health outcomes and targeted interventions should be taken to deal with different situations.
The Chinese college students in the “high domestic violence and childhood abuse” class were found to be more likely to have a higher degree of depression and anxiety, compared with their counterparts in the “low ACEs” class, which was consistent with the previous evidence showing positively associated between childhood abuse and witnessing intimate partner violence between parents and a greater level of depression in adulthood [59, 60]. The possible explanations are that witnessing household violence and physical, emotional or sexual abuse may reduce the level of resilient capacity in adulthood [49], thus leading to a higher level of psychological problems. Moreover, the unmet need for acceptance and love from parents due to the domestic violence may impair children’s self-esteem and emotional stability, and may distort their mental representations about interpersonal relationships, thus in turn creating a higher level of anxiety in them [50]. Additionally, compared with the “family dysfunction but low childhood abuse” class, the “high domestic violence and childhood abuse” class was nearly twice more likely to suffer from a higher level of depression and anxiety, indicating that childhood abuse may have more negative influence on the mental adaptive ability than household dysfunction.
To conclude, more attention should be paid on Chinese children exposed to high levels of domestic violence and childhood abuse as well as household dysfunction, and efforts are needed in three dimensions: 1) improve the public awareness of the long-term and potentially negative impacts of ACEs on mental health as well as the importance of early intervention for children having ACEs, 2) formulate and implement culturally sensitive and integrated interventions and policies to prevent or reduce all types of ACEs and ensure a safe growing environment for children in China, and 3) identify college students with specific patterns of ACE exposure and offer them targeted support, such as psychological counseling or education to correct the wrong values formed in the abusive or oppressive environments and to improve their psychological resilience to cope with adversities and sufferings in life, so as to mitigate the negative outcomes of ACE exposure on mental health in adulthood.
However, the findings should be cautiously interpreted considering the following limitations of this study. First, the convenience sampling limits the generalizability of the results, but the findings support most previous research indicating the positive relationship between ACE exposure patterns and mental health problems among college students and may provide inspiration for future research. Second, although all information was collected in the form of anonymous online surveys, retrospective self-reports of ACEs may still be biased from inaccurate recall or social desirability. However, given that college students are emerging adults, the recall bias may be relatively smaller than that of older adults or the general population. Third, this study did not account for timing and duration of ACEs, which may also have impacts on the incidence and intensity of depression and anxiety in adulthood. Fourth, this study included a period of the recent pandemic crisis, but the potential impact of COVID-19 on mental health was not considered. Finally, the cross-sectional design could not infer causation, although childhood adversities clearly preceded mental health disorders in adulthood.
Future research are suggested to use representative and prospective data to examine the association between ACE exposure patterns and mental health problems in Chinese college students, and to explore how ACEs specifically impact on mental health in adulthood. Additionally, due to the different results on the effects of co-occurrence of multiple household dysfunction, more evidence is needed to explore the specific influence of it. Last but not least, the influence mechanism of ACEs, such as the role of mental resilience and social support, should be examined to explore how different patterns of ACE exposures directly or indirectly affect mental health, thus providing evidence for targeted interventions.