Drinking behaviors by stress level in Korean university students.

The purposes of this study are to estimate the stress level of university students, and to verify the relationships between stress level and drinking behavior. A questionnaire survey was administered to 430 university students in the Gangwon area in Korea from November 5 to November 28, 2008, and data from 391 students were used for the final statistical analysis. The most stressful factor was "Worry about academic achievements" (2.86 by Likert-type 4 point scale). The subjects were divided into two groups, a low stress group (≤ 65.0) and a high stress group (≥ 66.0), by the mean value (65.1) and median value (66.0) of the stress levels. The drinking frequency was not different between the two stress groups, but the amount of alcohol consumption was significantly different (P < 0.05). The portion of students reporting drinking "7 glasses or over" was higher in the lower stress group than in the higher stress group. In addition, factor 6, "Lack of learning ability", was negatively correlated with drinking frequency and the amount of alcohol consumption (P < 0.05), and factor 3, "Worry about academic achievements", was negatively correlated with the amount of drinking (P < 0.05). The major motive for drinking was "When overjoyed or there is something to celebrate" (2.62), and the main expected effect of drinking was "Drinking enables me to get together with people and shape my sociability" (2.73). The higher stress group showed significantly higher scores on several items in the categories of motives (P < 0.01), negative experience (P < 0.05), and expected effects (P < 0.05) of drinking than the lower stress group. Our results imply that university students at the lower stress level may drink more from social motives in positive drinking environments, while those at the higher stress level may have more problematic-drinking despite their smaller amount of alcohol consumption.

Introduction

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.

Subjects and Methods

Subjects

A questionnaire survey was administered to 430 university students from November 5 to November 28, 2008. Inclusion criteria were as follows: students were at university in the Gangwon area in Korea. We selected subjects so as to include male and female students in different school years and with various majors. Subjects who refused the survey or submitted an incomplete response were excluded. In the end, data from 391 students were used for the statistical analysis.

The questionnaire

The questionnaire used for the study included three areas: general characteristics of the subjects, the stress level, and drinking behavior. For general characteristics of the subjects, gender, age, grade, monthly expenditure, satisfaction of expenditure, and health status were examined. The stress level was estimated by the Likert-type 4 point scale (1 = strongly disagree, 2 = disagree, 3 = agree, and 4 = strongly agree) based on 49 items of the perceived stress scale [25]. Referring to previous studies [10,26,27], drinking behavior was evaluated as follows: Frequency of drinking and amount of alcohol consumption were examined with each item as a nominal scale. Motives for drinking and expected effects of drinking were examined with 10 items each by the Likert-type 4 point scale. 10 items of negative experiences related with drinking were measured by the interval scale (0 = never, 1 = once in a while, 2 = sometimes, 3 = often, 4 = always).

Statistical analysis

Statistical analysis of the data from the survey was performed using the SPSS WIN 18.0 program. Descriptive analysis and frequency analysis were conducted for general characteristics and stress level of the subjects. In addition, cross-tabulation analysis (chi-square test) and independent t-test were performed to compare differences between the higher stress group and the lower stress group. To verify the reliability and validity of the measuring tools for the stress level, Cronbach's alpha value and a factor analysis were used. Pearson's correlation analysis was conducted to confirm the relationship between stress factors and frequency or amount of drinking.

Results

General characteristics of the subjects

General characteristics of the total subjects and subgroups by stress level are shown in Table 1. Of the total subjects, 56.8% were male students and 43.2% were female students. 66% of the subjects were under 23 and 34.0% were 23 years and over. Freshmen accounted for 44.1%, followed by sophomores 26.8%, juniors 15.5% and seniors 13.7%. Reported average monthly expenditure was over 300,000 won for 41.8% of the subjects, 200,000~300,000 won for 32.8%, and less than 200,000 won for 25.4%. 48.7% of the subjects were satisfied with their expenditure and 51.3% were not. For health status perceived by themselves, 64.5% of the subjects answered good.

Table 1

General characteristics by stress group

1) Subjects were classified by the mean value (65.1) and median value (66.0) of stress levels. The stress level of the lower stress group was ≤ 65, and that of the higher stress group was ≥ 66

2) N (%)

3) Subjects were classified by the mean value of age

4) Mean ± SD. The maximum score was 120, the multiplication of 30 items by 4 point on the Likert-type 4 point scale (1 = strongly disagree, 4 = strongly agree)

* P < 0.05, ** P < 0.01, *** P < 0.001

The subjects were divided into two groups, a lower stress group (≤ 65.0) and a higher stress group (≥ 66.0), according to the mean value (65.1) and median value (66.0) of the stress levels. A comparison of general characteristics between the two stress groups showed significant differences in gender (P < 0.001), age (P < 0.05), satisfaction with expenditure (P < 0.01), and health status (P < 0.001). The higher stress group consists of female students (51.9%), students aged less than 23 (71.8%), and those dissatisfied with expenditures (57.6%). Hence, the higher stress group features women and younger and the more unhealthy subjects.

Stress level

Analysis of reliability and validity

An analysis for reliability and validity of the perceived stress scale is shown in Table 2. In the first factor analysis for validity, 49 items were divided into 13 factors. Because some of them were at a low level of explanatory power and confused the meaning of factors, these were excluded, and the next factor analysis was then conducted. The level regarded as the optimum for validity was determined by repeating this process, and a total of 8 factors that consisted of 30 question items were decided upon as the final result of the validity test. After consideration of the attributes of items belonging to each factor, factor 1 with 6 variables was named "Pressed for time" (10.223% of variance), factor 2 with 4 variables "Conflict with friends" (9.731% of variance), factor 3 with 5 variables "Worry about academic achievements" (8.432% of variance), factor 4 with 4 variables "Sense of being alienated" (7.869% of variance), factor 5 with 5 variables "Maladjustment to school life" (7.091% of variance), factor 6 with 2 variables "Lack of learning ability" (6.778% of variance), factor 7 with 2 variables "Financial hardships" (5.632% of variance), and factor 8 with 2 variables "Conflict with the opposite gender" (5.293% of variance). These factors together accounted for 61.050% of the variance.

Table 2

Validity and reliability of stress scale

1) Mean ± SD, The Likert-tyep 4 point scale (1 = strongly disagree, 2 = disagree, 3 = agree, 4 = strongly agree)

2) Variance %

3) Total variance %

4) The maximum score was 120 (30 items multiplied by 4 points) on the Likert-type scale (1 = strongly disagree, 4 = strongly agree)

Reliability and internal consistency of the stress factors were assessed using Cronbach's alpha (Table 2). Cronbach's alpha coefficient of factor 1 was measured at 0.780, factor 2 at 0.796, factor 3 at 0.703, factor 4 at 0.775, factor 5 at 0.712, factor 6 at 0.660, factor 7 at 0.792, and factor 8 at 0.732. The stress instrument was found to have reliability coefficients well above 0.50, a level typically accepted as sufficiently reliable for the conduct of exploratory research. All of the 30 question items were used for subsequent analyses, because Cronbach's alpha of each item was not increased if any item was deleted.

Subject's stress level

In Table 2, the mean of stress levels for all subjects was 65.1, with a maximum possible score of 120. The most stressful item was "I am worried about the job in the future" (3.32), followed by "I am worried about the curriculum (lesson, major areas, etc.)" (2.89), "I am not satisfied with my scholastic performance" (2.87), "I have too many things to do at once" (2.77), "I have to keep close relationships" (2.67), and "My grades are below the expectation" (2.58). On the other hand, items with lower stress levels included "I don't like friends at school" (1.58), "I feel myself separated from society" (1.64), "I am ignored" (1.64), "I am criticized by my friends" (1.67), "I feel isolated in society" (1.68), "I am poor at reading" (1.71), and "I am spoken ill of by my friends" (1.79).

The factor with the highest stress level was factor 3, "Worry about academic achievements" (2.86), followed by factor 1, "Pressed for time" (2.35). Meanwhile, factor 2, "Conflict with friends" (1.80), and factor 6, "Lack of learning ability" (1.84) showed relatively low stress levels.

Drinking behavior

Frequency and amount of drinking

For the drinking frequency of the subjects, "1~2 times per week" showed the highest response rate, at 66.8%, and "never or little," at 13.6%, showed the lowest (Table 3). There was no significant difference in the drinking frequency between the two stress groups. When asked about amount of alcohol consumption, 55.4% of the total subjects reported consumption of "7 glasses or over," indicating that the amount of drinking at a time is substantial among university students. The amount of alcohol consumption was significantly different between the stress groups (P < 0.05). The portion of subjects reporting drinking "7 glasses or over" was 61.1% in the lower stress group. In the higher stress group, consumption of "3 glasses or less" was reported by 17.1% and consumption of "4~6 glasses" by 27.3%. It can be inferred from these findings that the subjects with a low stress level drink more. We analyzed subgroups by sex, but there was no significant difference in the drinking frequency or the amount of alcohol consumption.

Table 3

Frequency and amount of drinking by stress group

1) N (%)

* P < 0.05

We analyzed correlations between stress factors and drinking behaviors (Table 4). Factor 6, "Lack of learning ability" showed a negative correlation with drinking frequency (P < 0.05). Factor 3, "Worry about academic achievements" and factor 6, "Lack of learning ability" were negatively correlated with the amount of alcohol consumption (P < 0.05).

Table 4

Correlation analysis for stress factors and drinking behaviors

1) Correlation coefficients

* P < 0.05

Motives for drinking

The strongest motives for drinking reported by the subjects were "When overjoyed or there is something to celebrate" (2.62) and "When offered to drink while hanging out with people" (2.58) (Table 5). On the other hand, the response rate was relatively low for "When I feel tired" (1.31) or "When I get injured or feel pain in the body" (1.22). Statistical analysis of motives showed that the higher stress group gave significantly higher scores than the lower stress group for the items "When depressed" (2.12), "When I am worried about something" (2.09), and "When I am upset" (2.23) (P < 0.01).

Table 5

Motives for drinking by stress group

1) Mean ± SD, The Likert-type 4 point scale (1 = strongly disagree, 2 = disagree, 3 = agree, 4 = strongly agree)

** P < 0.01

Negative experience related with drinking

We investigated negative experiences related with drinking (Table 6). The scores for the 10 items examined were all below 1.0, showing that the level of negative experiences was low for the subjects. While the two items "I failed to be on time or keep promise due to drinking" (0.99) and "My parents got angry and worried about my drinking" (0.93) obtained relatively high scores, "I threw away or broke something while drinking" (0.22) and "I was injured in the accident due to drinking" (0.19) were given extremely low scores.

Table 6

Negative experience related with drinking by stress group

1) Mean ± SD, The interval scale (0 = never, 1 = once in a while, 2 = sometimes, 3 = often, 4 = always)

* P < 0.05

A comparison of negative experiences related with drinking between the two groups indicates that the higher stress group showed a significantly higher score on "I had trouble with improving my school work or academic achievements because of drinking" than the lower stress group (0.86 vs. 0.62) (P < 0.05).

Expected effects of drinking

The main effects of drinking expected by university students included the following items: "Drinking enables me to get together with people and shape my sociability" (2.73), and "Drinking helps me open up my mind and express myself easily" (2.35) (Table 7). On the other hand, "Drinking makes me feel more sexually attractive" (1.31) and "Drinking makes me feel optimistic for the future" (1.24) obtained low scores.

Table 7

Expected effects of drinking by stress group

1) Mean ± SD, The Likert-type 4 point scale (1 = strongly disagree, 2 = disagree, 3 = agree, 4 = strongly agree)

* P < 0.05

An analysis of the expected effects of drinking by stress group indicates that the higher stress group (1.88) showed higher expectations for "Drinking enables me to present my opinion and convey it confidently" than the lower stress group (1.67) with significant difference (P < 0.05). In addition, the higher stress group (1.96) showed higher expectations for "Drinking helps me ignore people's attention" than the lower stress group (1.75) (P < 0.05).

Discussion

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.