Drinking behaviors by stress level in Korean university students

Drinking in modern society means more than simply ingesting alcohol. Drinking behavior also conveys social and emotional meanings. Drinking plays a role in enhancing positive emotions during social gatherings such as anniversaries, festivals, and other events, as well as in developing interpersonal relationships. In addition, drinking serves as a means to alleviate tension and pains caused by environmental and mental stress in undesirable situations [1]. Korea has a distinctive drinking culture which is fairly positive and permissive, compared with other countries. In Korea, drunken behaviors are generously accepted, people even boast of the large amount of alcohol they can drink, and liquor can be easily purchased. This causes problems of overconsumption and alcoholism [2, 3]. According to The Survey on National Health and Nutrition 2010, 77.8% of male and 43% of female adults over 19 years drink more than once a month. These data reveal that the percentage of Korean males who drink is higher than that of males in the United States, while the percentages of females are similar [4, 5].

A psychiatric study reports that the modernization and industrialization of society have contributed to the increase in environmental and mental stresses, resulting in increases in drinking [6]. Conger proposed a theory that people tend to drink alcohol under stress because alcohol allegedly has effects on alleviating tension [7]. Subsequent studies confirmed that stressful situations trigger drinking [8, 9]. Some studies have verified that a high perceived stress level is positively correlated with drinking frequency [10], and that the level of stress in daily life is a predictive factor for drinking [11]. However, although many attempts have been made to identify the relationship between stress and drinking [7-9], that relationship is not yet clear, and it remains controversial to date. Some studies have reported that stress and drinking are not related [12, 13]. Recent studies suggested that the relationship between stress and drinking varies depending on the type of stress [14, 15] and the ethnic group [16].

In Korea, university students are freed from the restrictions of their high school days and are officially allowed to drink. Campus life at university is the early stage of individuals' drinking behavior, and drinking-related problems grow rapidly during this period [17, 18]. It was estimated that 90% or more of Korean university students drink [19, 20], which is higher than the 75.9% of corporate employees in Korea [21] and the 70% of university students in the US who drink [22]. A survey conducted on female university students indicated that 92.4% of female students drink and 25.2% of them have experienced drinking-related problems, highlighting the seriousness of drinking behavior in university students [23].

University life is a transition period for students to become independent entities in society, and students experience various stresses caused by conflicts with friends, getting a job, schoolwork, and financial problems during that period [24]. Therefore, we wished to investigate the relationship between stress and drinking for university students, who are exposed to different stresses from those experienced by adults. The purposes of this study are to estimate the stress level of university students in Korea and to verify that stress level is related with drinking behavior, including drinking frequency, amount of alcohol consumption, motives for drinking, negative experiences related with drinking, and expected effects of drinking.

In this study, we showed that drinking behavior is related with the stress level of university students. The subjects were divided into lower and higher stress groups, and drinking behaviors between the two groups were compared. There were significant differences between the two groups in drinking behaviors such as amount of alcohol consumption, motives for drinking, negative experiences related with drinking, and expected effects of drinking. We confirmed that some drinking behaviors depend on stress levels.

While there was no difference in drinking frequency by stress level, the lower stress group showed a significantly higher level of alcohol consumption, compared with the higher stress group. This finding proves that a relationship exists between stress level and amount of alcohol consumption. In addition, amount of alcohol consumption was negatively correlated with stress factors such as "Worry about academic achievements" and "Lack of learning ability", and drinking frequency was also negatively correlated with "Lack of learning ability". This implies that the less schoolwork-related stress university students have, the more they drink. Our finding is consistent with Park and Lee's study asserting that students, who feel stressed about their future, drink less frequently [28]. This is presumably because university students drink voluntarily in positive and pleasant situations, unlike corporate employees, who normally drink with their boss and co-workers in negative situations to relieve the stress from the workplace [21]. Farber et al. [29] and Bradizza et al. [1] divided drinking motives largely into two categories, namely, "a coping motive", a motive of drinking to relieve negative emotions such as personal problems, and "a social motive", a motive of drinking to promote positive emotions and enjoy social activities such as festivals. Considering that young adolescents largely drink from the motives of facilitating social interactions, enhancing social events, and so forth [30, 31], it is postulated that the younger a person is, the more he or she tends to drink from social motives. A study on university students in the Ulsan area suggested that they drink largely on occasions such as "anniversary" (40%) and "social gathering with people" (34%), while "alleviating stress" is at a minimal 6.0% [32]. Our study also showed that students mostly drink "When overjoyed or when there is something to celebrate" and "When offered to drink while hanging out with people". Our findings support the idea that university students largely drink positively from social motives, while they seldom drink from negative motives such as coping motives. Moreover, a comparison of drinking motives by stress groups found that the lower stress group shows significantly lower scores than the higher stress group on items such as "When I am upset", "When depressed", and "When I am worried about something", further indicating that subjects at low stress levels do not drink from coping motives. A domestic study on university students reported that drinking behavior varies depending on the motives for drinking [10], and another study demonstrated that students who drink from social motives do not drink as frequently but drink a lot at a time, findings similar to the results of our study [28]. Students at a low stress level, who drink mainly from social motives, seem to be more sociable and have more opportunities to drink to develop close relationships, thus inducing themselves to drink more. However, corporate employees tend to drink from social pressure and negative issues, indicating that they drink more from coping motives [33]. These findings imply that university students' drinking behaviors differ from those of corporate employees. Experimentation in animals has suggested that acute stress reduces the amount of alcohol consumption, while chronic stress raises it [15]. Because university students have been exposed to stress for a short time compared to adults and the elderly, short-term stress may reduce the amount of alcohol consumption. However, contrary to our results, findings of other studies have also suggested both that stress stimulates drinking [34] and that stress is not associated with drinking [12, 13]. These conflicting results show that the relationship between stress and drinking is very complicated, and it is thought that results of studies could vary depending on the kind of stress, motives for drinking, and the characteristics of the subjects.

Our findings for negative experiences due to drinking showed that university students have relatively few experiences of drinking problems. This is different from other studies reporting that the drinking problems of university students are serious and substantial [32, 35, 36]. However, the higher stress group in our study scored significantly higher than the lower stress group on the item, "I had trouble with improving my school work or academic achievements because of drinking", thus suggesting that the subjects at a higher stress level may have more drinking-related problems in spite of their smaller amount of alcohol consumption. One study on female university students demonstrated that perceived stress directly affects drinking-related problems [37]. Han et al. [23] also reported that perceived stress levels and drinking-related problems have a positive correlation, and that the problematic drinking group shows a higher level of perceived stress and stress symptoms than the control group does. In addition, Lee reported in his study on male and female students that problems after drinking are closely related with the stress of daily life [11]. These findings correspond to those of the present study. Meanwhile, some studies have reported that drinking problems of university students tend to occur under extreme emotional conflict or feelings of being alienated [38, 39]. The current study has also found that students in the higher stress group with drinking-related negative experiences, which cause trouble with schoolwork and scholastic performance, scored higher on items of expected effects of drinking such as "Drinking enables me to present my opinion and convey it confidently" and "Drinking helps me ignore people's attention" than the lower stress group did. These results suggest that the higher stress group has an emotionally problematic tendency of lacking in self-confidence and sociability, and of feeling alienated from others. In addition, a previous study suggested that in the case of female university students, the more serious drinking-related problems are, the more the students use drinking for emotional coping [23]. Other studies also reported that social anxiety or social phobia is related with alcohol consumption [40-42]. Savette attributed this phenomenon to the effects of alcohol on cognitive processes, resulting in relief of social anxiety, and suggested "an appraisal disruption model" [43]. In line with previous results, students expect to solve problems relating to social interaction and personal relations by means of drinking. Therefore, effective management for the stress arising from interpersonal relations is essential to the prevention of drinking problems. Moreover, appropriate university-wide education programs should be prepared in universities.

This study has several limitations. First, since drinking frequency and amount of alcohol consumption were measured on a relative scale, actual alcohol consumption may be a little different. Second, the generalization of our results may be limited by the fact that the survey was carried out only for university students in a specified region. Third, since the current study uses a cross-sectional design, further longitudinal studies are needed to clarify cause-and-effect relationships between stress from daily life and drinking behavior. Lastly, the present study did not take into account the inherent differences between male and female subjects. We analyzed subgroups by sex only for frequency and amount of drinking by stress group. The physiological response to alcohol differs between males and females [44], and women are often restricted in drinking by their unique gender roles, including pregnancy and delivery [20, 45]. Prospective studies with a large sample size on a national scale and experimental studies measuring alcohol consumption accurately are required to overcome these limitations. We also plan further investigation which makes a comparison between male and female students. In spite of such limitations, our results imply that university students on a lower stress level may drink more from social motives in positive drinking environments, while those on the higher stress level may have more problematic drinking despite smaller amounts of alcohol consumption. Our results differ from the general hypothesis that stress may stimulate drinking or increase the amount of alcohol consumption. These findings will be helpful to understand drinking behavior and prevent drinking problems among university students, and will also provide these students a guide to develop proper drinking behavior as adults.