Medical student depression and its correlates across three international medical schools

ARTICLE HIGHLIGHTS

Research background

Medical students have high rates of depression and burnout. These high rates are also seen internationally, including in populations in Asia and the Middle East. While burnout and depression affect the student’s academic performance, decrease empathy, and increase unprofessional behaviors, very few students seek mental health treatment when they need it. Some studies have examined explanations for the high rates of burnout and depression. For depression, predictors included mistreatment, poor role models, low optimism, gender, and year of study. The overall learning environment was most often cited as a reason for burnout, with other explanations ranging from specific grading schemes to sleep. To our knowledge, no study has compared depression in medical students from different international populations. Additionally, we are unaware of other studies that have examined whether there are differences in other variables across international sites, including age, gender, sleep, exercise, unmet mental health needs, emotional exhaustion, stress, as well as nationality, which may explain any differences in depression. This study seeks to add to the literature by examining both of these questions and reporting on the data from three different groups of medical students, each from an internationally distinct medical school: Yale University School of Medicine in the United States (US), Central South University Xiangya School of Medicine in China, and a School of Medicine in the Middle East whose research collaborators chose to remain anonymous.

Research motivation

The motivation behind this research is that depression and burnout in medical students affect patient care outcomes, and also contribute to high suicide rates among medical students and physicians. We have yet to fully understand why medical students have such high rates of depression and burnout, nor do we understand the global scope of the problem. We hope that by looking at these questions, we can better develop interventions to address depression in medical students. Currently, no best-practices exist, so a better understanding of the correlates of depression and need for site-specific interventions is warranted.

Research objectives

The primary aim of this research was to compare depression rates in medical students across three internationally distinct populations. By doing so, we hoped to examine and better understand the universality of depression in medical students. The secondary aim of this research was to examine whether there are differences in other variables across these sites, including age, gender, sleep, exercise, unmet mental health needs, emotional exhaustion, stress, as well as nationality, which may explain any differences in depression. By doing so, we hoped to better understand the correlates of depression in medical students, as well as develop a better understanding of cross-cultural differences. The importance of looking at both of these aims is to better describe depression and its correlates in medical students, which can then help determine intervention strategies or identify additional variables to be studied in the future.

Research methods

Convenience samples of medical students from the US, China, and a Middle Eastern country were surveyed in this exploratory study. Incentives were only offered at Yale (a gift card raffle), and participation was confidential, anonymous, and voluntary at all sites. The authors designed the survey utilizing some previously validated questionnaires for more accurate results. The Patient Health Questionnaire-2 measured depression, and a positive screen was defined as a PHQ-2 score of ≥ 3. A modified version of the Maslach Burnout Inventory (MBI) assessed burnout. Prior to analyzing the survey data, principal components analysis was used to analyze the modified MBI and develop a component called “emotional exhaustion”, which had high component loadings on the first four survey items about feeling drained, used up, burned out, or uninterested. Other questions on variables like sleep, exercise, and mental health need were assessed with self-reported multiple-choice questions. The original survey was translated into Mandarin, and by a language native to the Middle Eastern country by contributing authors. The translations were then re-translated back to English by colleagues in the US who were fluent in both languages to assure that the surveys administered to all cohorts of students were compa-rable. Chi-square test and analysis of variance were used to examine differences in demographics, behavioral, and psychological variables across these three schools. Analysis of covariance (ANCOVA) was then used to compare depression among these three countries adjusted for differences in “unmet mental health needs”. Unmet mental health need was defined as rating one’s agreement with the Likert scale item “There are times I have a mental health need for which I do not seek care”, where agree and strongly agree were collapsed into one response. To determine the possible predictive variables for medical student depression, multiple linear regression analysis was performed. The analysis included: demographic variables (age and gender), behavioral variables (sleep, exercise, unmet mental health needs), and psychological variables (stress, emotional exhaustion). The possibility of multicollinearity was ruled out. All analyses were done using SPSS version 25, and statistical significance was evaluated at the P < 0.05 level.

Research results

Response rates differed by cohort. At Yale, 205 out of 519 students (39.5%) responded to the survey. At the Middle Eastern school, 172 out of 203 students (84.7%) and at Xiangya, 142 out of 150 (94.7%) responded to the survey. Students in the Middle Eastern country were significantly more likely to screen positive for depression (41.1% of students screened positive) than students in China (14.1% screened positive). Both cohorts were more likely to be depressed than the US cohort (3.8% screened positive). Students in China slept the least number of hours, and students in the Middle East exercised the least. More students in the Middle Eastern school had unmet mental health needs. When ANCOVA was used to adjust for unmet mental health needs, the students from the Middle Eastern country continued to have significantly higher rates of screening positive for depression, followed by China, and then the US. ANCOVA was also used to adjust rates of emotional exhaustion by PHQ-2 scores, and students from the US reported significantly higher scores than those from each of the other countries. The scores from the students in China and the Middle East were not significantly different from each other. Results from the multiple linear regression analysis on medical student depression found that demographic variables did not significantly predict medical student depression. Among behavioral variables, exercise and unmet mental health needs significantly predicted medical student depression, but amount of sleep did not. Both psychological variables, stress, as well as the emotional exhaustion component of burnout, were predictors of medical student depression. Stress was measured by answering “yes” to the question “are you stressed?”. Admitting stress was negatively related to depression (i.e., more stress, less depression). In comparison to the US, coming from the Middle Eastern country and China predicted higher levels of depression. The total model explained 47% of the variance of medical student depression (F = 41.621; df = 9,418; P < 0.001). The effect size (i.e., Cohen's f² = 0.90) was large. Our results contribute to the field, as we found statistically significant differences in depre-ssion across our three international cohorts, and differences in other correlates, like emotional exhaustion, sleep, and unmet mental health needs, which had not previously been described. We also found that our model only predicted 47% of depression, with region as the greatest predictor. While this identified some of the potential correlates for depression, including unmet needs that could be better targeted in each program, our results also show that there are inherent differences by region that need to be further assessed. For example, future studies might explore the relationship between motivations for entering medicine (e.g., personal desire vs family/societal pressures) and emotional distress among medical students. Equally important is to investigate the effectiveness of interventions designed to support student mental health to better understand ways to improve these high rates internationally.

Research conclusions

This study found that depression, as measured by the PHQ-2, was highest among students in the Middle East, followed by China, and then the US. Emotional exhaustion was highest, however, in the US. Linear regression suggested emotional exhaustion, stress, unmet mental health need, region, and exercise predicted nearly half of depression in these cohorts. Even though the study design only involved three medical schools and may not have been broadly representative of medical students in the three countries, or other medical universities in these countries, we know that depression is a key problem in medical students internationally, it varies between groups and region, and other site-specific factors are important reasons for these high rates. We also know that unmet mental health needs must be addressed. Although rates of depression vary among the three groups studied, and response rate differences might have influenced the outcomes, our results suggest that continued efforts toward identifying site-specific prevention and intervention strategies in medical student mental health are warranted, and that additional socio-cultural variables should be studied.

Research perspectives

In carrying out this research, the authors learned that while specific curricula are unique at each individual medical school, medical students in three countries share common experiences and stressors: Competitive entry to medical school, and the pressure and academic rigor of studying to be a physician. For some students, these experiences can lead to depression and burnout. The reasons behind this are complex, and further research is warranted to fully elucidate them. In this study, the authors also learned a great deal about international collaboration. This was a rich experience, yet came with some unplanned challenges. For example, one important lesson learned is that when translating surveys, they should always be translated back into the original language before administration to assure the questions read as originally intended. Additionally, with the request by one collaborating institution for anonymity in publication, we learned that sometimes there is difficulty in acknowledging the reality of depression and burnout among students by the authorities of schools. This can limit research studies in their dissemination. Future research should further explore site-specific factors associated with depression. One way to do this would be to include focus groups that help inform survey design. This might allow for a more complete picture of depression and associated factors across internationally distinct medical school sites.