This study was conducted to assess the prevalence of GI symptoms in Korean students (n = 715) enrolled in an associate degree nursing program and to examine the association between perceived stress and GI symptoms, using a cross-sectional descriptive study design. The biopsychosocial model outlined by Engel served as the main framework guiding this study.
According to the results, 65% of nursing students experienced more than one GI symptom and 31.1% of students experienced more than three GI symptoms over the past three months. Students reported upper dysmotility symptoms (postprandial fullness, bloating, abdominal symptoms) and bowel symptoms (diarrhea/constipation). Those students who reported higher perceived stress were significantly more likely to complain of GI symptoms. Thus perceived stress was significantly associated with GI symptoms among nursing students.
The prevalence of GI symptoms in Korean nursing students is similar to other reports. According to studies from North American, the prevalence of GI symptoms in a population-based survey was 61.7% of 1,149 Canadians  and 69% of 5,430 U.S. householders . In the Greek general urban population, 53% reported more than one GI symptom during the past week and 55% during the past 6 months . In addition, the prevalence of GI symptoms in students was 51.2% of 127 Canadian university students  and 64.2% of 668 university students in Switzerland .
Nursing students reported that the most frequent GI symptoms were the upper dysmotility symptoms and the bowel symptoms. Previous studies reported that the upper dysmotility symptoms were the most common type of GI symptoms [14, 23, 24]. However, the bowel symptoms were more common in Asians, while the esophageal symptoms were more common in Europeans [6, 7, 25]. Possible explanations for the lower prevalence of esophageal symptoms include the facts that Asians generally have a lower fat diet, a lower BMI, and a lower gastric acid output than Westerners .
In the present study, we found an association between perceived stress and GI symptoms among Korean nursing students. The association remained significant in analyses adjusted for subjective health status. This finding agrees with a biopsychosocial model. Perceived stress caused by high academic and clinical demands threatens the homeostasis of students and can have both a short- and long-term influence on the function of the GI tract . A European cross-national study reported that university students with a high level of psychosocial stress were more likely to report psychosomatic complaints (OR 2.32; CI 1.86-2.89), including neck ache/backache (OR 1.34; CI 1.08-1.66), as well as GI complaints (OR 1.39; CI 1.12-1.71) . Another European study showed that GI symptoms were significantly predicted by increased levels of perceived chronic stress, dispositional stress reactivity, and use of maladaptive coping strategies . A similar association was reported in Korean studies. Han and colleagues reported that a high level of stress was significantly associated with irritable bowel syndrome (IBS) among medical, dental, and nursing students . In addition, IBS was significantly predicted by increased levels of psychological stress (OR 1.87; CI 1.18-2.99) among participants in a health screening program . Thus, the significant association between perceived stress and GI symptoms among Korean nursing students was confirmed in this study. This conclusion can be considered supportive evidence for the biopsychosocial model.
According to the results, subjective health status had a negative association with perceived stress and GI symptoms. A study, using the Cross-National Student Health Survey in Germany, Bulgaria and Poland, reported that subjective health status for university students had a strong association with psychosomatic complaints as well as physical and psychological health . Cross-sectional approaches do not allow conclusions about causations. Thus, future studies are needed to investigate the causation among subjective health status, perceived stress, and GI symptoms. On the other hand, subjective health status is a feasible way to assess health in nursing students because it has been shown to have high reliability, validity, and predictive power for a variety of illnesses and conditions .
The prevalence of GI symptoms was 53.1% in male students in this study. It was slightly lower than female students (66.1%). Although gender differences were reported among general university students [15, 26], it has not been confirmed in medical, dental, and nursing students [27, 31]. Therefore, future studies are needed to investigate the relationships among gender, perceived stress, and GI symptoms between nursing students and others types of students. On the other hand, male students' health has been ignored in a predominantly female discipline such as nursing. Thus, nursing educators should also be concerned about stress-related diseases in male nursing students. The prevalence and risk factors for male nursing students should be examined.
This study has several limitations. First, our study participants consisted of a convenience sampling that might influence the generalizations of our results to the nursing students in Korea. Second, the design of this study was cross-sectional, which does not allow for a causal interpretation of our results. Third, a potential limitation of our study is the use of self-reporting measures for GI symptoms, although high correlations between diagnoses from questionnaires and from physical examinations have been reported . Fourth, this study did not take into account other potential determinants of GI symptoms such as the use of non-steroidal anti-inflammatory drugs (NSAIDs). Fifth, data collection immediately after taking a final exam might influence one's perceived stress level and prevalence of GI symptoms, although results from this study are in line with several other reports [14, 15, 26–28].
Despite these limitations this study has several important strengths. To our knowledge, no previous study has assessed the prevalence of GI symptoms in nursing students. This study identifies the prevalence of GI symptoms and frequency of reported GI symptoms among Korean nursing students. In addition, this study revealed the association between perceived stress and GI symptoms in nursing students.
Based on the results, we suggest including stress management programs in formal and informal curriculum for nursing students. According to a systematic review for effectiveness of a stress management program in student nurses, the most effective interventions included skills for coping with stressful situations such as cognitive reappraisal and relaxation . Thus, a stress management program focused on cognitive reappraisal training and physical and psychological skills for coping will contribute to the reduction of GI symptoms in nursing students.