Medires Publishers - Article

Abstract

Introduction: Globally, the prevalence of depression is on the increase affecting about 5% of the adult population. University undergraduates’ particularly medical students are at a high risk of experiencing depression due to academic workload and demands in studying in the university. Depression among medical students is a significant public health concern. Despite several studies on depression among medical students worldwide, there is scarcity of studies on depression among medical students at the university of the Gambia. This study was therefore conducted to determine the prevalence and factors associated with depression among medical students at the University of Gambia.

Methodology: This was a cross-sectional prevalence study conducted among 160 preclinical and clinical medical students of the University of the Gambia who met the inclusion criteria. The Patient Health Questionnaire-9 (PHQ-9) questionnaire was self-administered to the students. For making diagnosis of depression, PHQ-9 scores of ≥ 10 confirm the diagnosis. Data was analyzed using the Statistical Package for Social Sciences (SPSS) version 20. Frequency and percentages were used to summarize descriptive statistics while association between categorical variables was determined using Chi-square with level of statistical significance set at P<0.05

Result: Overall, 160 medical students participated in the study. The mean age of the students was 23.9years with a median of 24.0 years. Most of the students (62.5%) were within the age range of 18-24 years and a majority was female (58.1%). Most participants were single (91.9%) and came from middle-class backgrounds (65.6%). A majority (27.5%) of the students was in their seventh-year (final year). The prevalence of depression among the students was 68.1%. Among the students who met criteria for depression, 30% of them had mild depression while 25% and 13.1% had moderate and severe depression respectively. Factors contributing to depression among the students included living arrangements, with most students living with family (55.6%), poor sleep quality (58.1%), poor academic performance (43.8%), and academic failure (50.0%) with academic pressure representing the most common stressor (80.6%). Gender was significantly associated with depression, with higher rates among females (p=0.010). Medical school curriculum (p<0.001), Financial issues (p=0.043) and poor personal relationships (p=0.008) were significantly associated with depression. 

Conclusion: The study reveals a high prevalence of depression among the medical students. A variety of risk factors identified in this study included socio-demographic, academic, and lifestyle factors. The findings of this study point to an urgent need for more research into the causes as well as early diagnosis of depression using standardized tools. The need of making psychiatric services, counseling as well as support services available to susceptible students is highly imperative as these will improve mental health and academic performance of medical students.

Introduction

Depression is a common mental disorder that presents as depressed/low mood, loss of interest or pleasure in normally enjoyable activities and low self-esteem for at least two weeks [1, 2]. Depression is considered the leading cause of disability in the world today and is likely to become the second largest and most important disease by 2030 [3, 4]. It causes great suffering and economic loss to those affected and to society at large. There is also an increasing prevalence of depression among young people [5, 6].

Depression is among the most treatable mental disorders. Between 70% and 90% percent of people with depression eventually respond well to treatment (7). The annual prevalence of depression is quite high, even though it is significantly under-diagnosed [8]. About 3.8% of the population experience depression, with approximately 5% of adults affected (4% among men and 6% among women), and a prevalence of 5.7% among adults aged over 60 [9]. Globally, an estimated 350 million individuals are affected by depression [10]. It is 50% more prevalent among women compared to men [11]. More than 10% of pregnant women and new mothers across the globe struggle with depression [12]. Sadly, more than 700,000 lives are lost to suicide annually, making it the fourth leading cause of death among 15–29-year-olds [13].

Depression is a complex disease, and its onset and development is influenced by several biological, psychosocial and genetic factors. Given this complexity, university students, especially medical students, represent a group that is vulnerable to the disease, as they deal with stressors, insecurities, internal and external demands throughout their undergraduate studies [14, 15]. The other reasons for stress on students are the short period of the study compared to the enormity of the curriculum, the change in the method of reading, the acceleration in medical science update, lack of proper guidance for communication/failing in exams, inadequate time for clinical phase, insufficient bedside teaching, social stress, limited relationship with peer groups, change in the way of education, physical stress, unsuitable residence facilities, poor residence, food, etc. [16].

It is estimated that the prevalence of depressive disorders is higher in medical schools when compared to the general population [17].

The impact of this illness can extend to various aspects of an undergraduate student's life, including academic performance, future doctor-patient interactions, and social connections [18]. Those experiencing this condition might exhibit a notable decline in interest or enjoyment in their daily activities, along with disruptions in appetite and sleep, impaired psychomotor functions, feelings of worthlessness and guilt, and diminished cognitive abilities for decision-making [4]. If left untreated, these symptoms inevitably affect the trajectory of their professional development.

Despite the pervasive nature of depression among medical students, it remains a taboo subject in many academic institutions, shrouded in silence and stigma. The prevailing culture of stoicism and self-sacrifice within the medical profession discourages students from seeking help or disclosing their struggles for fear of discrimination and other repercussions [19]. Consequently, many suffer in silence, handling their mental health challenges alone, and often at great personal cost [20].

It is therefore important to investigate depression among medical students with a view to early detection and proffering possible solutions [21]. This becomes even more relevant in developing countries especially The Gambia with scarcity of studies on depression among medical students.

Methods

The study was conducted at the University of the Gambia. The University of the Gambia was established in 1999 by an act of parliament, making it the first and only public university in the Gambia. Its establishment was aimed to meet the growing demand for higher education and contribute to national development

The Medical School of the University of The Gambia, known as the Faculty of Medicine, Nursing and Health Sciences, was established in 1999. It was founded alongside the University of The Gambia itself. There were 350 medical students which comprised 189 in preclinical and 161 in clinical school at the time of the study.

The study was a cross-sectional prevalence study of medical students of University of The Gambia who constituted the study population.

Sample size for the Prevalence Study was determined using Leslie-Kish formula for single Proportion

P is the prevalence of depression among medical students and this was reported 24.7% [22]

q = 1- P

d = the precision of the study and for this study, which is chosen as 5%

Za = 1.96 (for 5% level of significance) is standard normal deviate

Using the prevalence rate of poor sleep quality among medical students ranging from 70-76% (27), then P= 0.76 and q= 0.24

n0    =   286

Finite Population Correction for population less than 10,000

Total Number of Medical Students =350 and this number is Less than 10,000.

So, applying Finite Population correction using the Formula for Finite Population Correction by Isreal GD et al, [23]

n0 = sample size = 285

N = Total Number of Medical Student=350

n = adjusted sample size

Final adjusted sample n = 160 Medical Students

Data for this study was collected using the Patient Health Questionnaire 9 (PHQ-9) [24]. The Patient Health Questionnaire 9 (PHQ-9) is a validated and widely used multipurpose instrument for screening, diagnosing, monitoring and measuring the severity of depression. The PHQ-9 incorporates DSM-IV depression diagnostic criteria with other leading major depressive symptoms into a brief self-report tool. The PHQ-9 is brief and useful tool in clinical practice as it can be completed by the patient in about 10 minutes and rapidly scored by the researcher [25]. There are 9 items scored similarly to PHQ-2 (0 to 3 for each item). The score ranges from 0 to 27. Question 9 is a single screening question on suicide risk. A patient who answers yes to question 9 needs further assessment for suicide risk by an individual who is competent to assess this risk [26]. For interpretation of scores: (5 – 9) minimal symptoms, (10 – 14) minor depression, (15 – 19) moderate depression, and >20 for severe depression. For making diagnosis of depression; PHQ-9 scores of 10 and above confirms the diagnosis. PHQ-9 scores ›10 had a sensitivity of 88% and specificity of 88% for major depression [27].

The questionnaire also included a section assessing socio-demographic variables such as age, sex, socio-economic status, and marital status, year of study, and lifestyle factors (smoking, physical activities, alcohol use, sleep quality etc.) and academic factors.

The questionnaires were self-administered to the students during their free time with simple random selection of students in third year to the seventh year as shown below:

Third Year medical students: 20

Fourth Year medical students: 32

Fifth Year medical students: 31

Sixth Year medical students: 33

Seventh Year medical students: 44

All eligible students who met inclusion criteria and consented to the study completed the questionnaire. Each questionnaire took no more than 20 minutes to complete. Anonymity and confidentiality were upheld.

Ethical approval letter with Reference Number EFSTH_REC_2024-091 was obtained from Research Ethics Committee of Edward Francis Small Teaching Hospital (EFSTH). Informed consent was also obtained from each participant. Students’ participation was entirely voluntary and students could pull out of the study at any point without any consequences. Data obtained were also kept confidential.

The collected data was analyzed using Statistical Package for Social Sciences (SPSS) version 20. Descriptive statistics such as frequency and percentages were used to summarize participants’ socio-demographic characteristics, academic factors, sleep quality, and lifestyle behaviors. Chi-square tests were performed to determine the associations between depression and various independent variables, including socio-demographic, academic, sleep, and lifestyle factors. A p-value < 0.05 was considered statistically significant.

Results

Socio-demographic profiles of the patients are reported in Table 1. The study included 160 medical students. The majority of participants were aged 18-24 years (62.5%) with mean (SD) age of 23.9 (1.4) years. Majority of the participants (58.1%) were females. Most of the students were single (91.9%) and 65.6% of the participants belonged to the middle class. The distribution of participants by year of study ranged from third-year (12.5%) to seventh-year (27.5%) which was the largest. This distribution suggests that most of the participants were relatively young, unmarried, and from middle socioeconomic backgrounds.

Table 1: Socio-demographic characteristics of study participants

Prevalence of depression, suicidal ideation, alcohol use, smoking and recreational drug use is reported in Table 2.

The findings presented in Table 2 reflect the prevalence of depression, suicidal ideation, alcohol use, smoking and recreational drug use among the study participants. Only 1.2% reported smoking cigarette while 11.9% reported drinking of alcohol. Use of recreational drugs was reported among 0.6% of the participants. Among the participants, 15% had suicidal ideation or thoughts of self-harm. The prevalence of depression among the medical students was 68.1%. The severity of depression varied, with 31.9% classified as having normal mental health, 30.0% experiencing mild depression, 25.0% moderate depression, 13.1% severe depression.

Table2: Depression, suicidal ideation, smoking, alcohol and recreational drug use.

The relationship between depression and socio-demographic factors was analyzed and presented in Table 3. Among the socio-demographic factors, it was only gender that was significantly associated with depression (p=0.010), with a higher prevalence of depression among females (44.4%) compared to males (23.8%). However, there was no significant relationship between depression and age, marital status, or socioeconomic status (p>0.05).

Table 3: Relation between depression and socio-demographic factors

The relationship between depression and academic factor is presented in Table 4. There was no significant association between living arrangements and depression (p=0.180). However, the medical school curriculum significantly impacted students' mental health (p<0.001), with 46.2% of participants reporting that the curriculum significantly affected their mental health thereby experiencing depression. Financial issues were significantly associated with depression (p=0.043), as were personal relationships (p=0.008). Academic pressure was prevalent as 80.6% of participants reporting it as their primary source of stress, but there was no significant relationship between academic pressure and depression (p=0.670). Sleep quality showed a non-significant relationship with depression (p=0.092), with poorer sleep quality linked to higher depression rates.

Table 4: Relationship between depression and academic factors

The relationship between depression and lifestyle factors is presented in Table 5.  Dietary habits were significantly related to depression (p=0.010), with participants who rated their dietary habits as poor more likely to report depression. Physical exercise, smoking, alcohol consumption and recreational drug use were not significantly associated with depression (p>0.05) however, sleep quality showed a non-significant significant association (p=0.092), indicating that poorer sleep quality may be linked to depression

Table 5: Relationship between depression and lifestyle factors

Discussion

The results of this study indicate a high prevalence of depression among medical students, with 68.1% of participants experiencing some level of depression. This is consistent with previous research showing that medical students have higher rates of depression compared to the general population. Rotenstein et al., who conducted a systematic review and meta-analysis, reported a global prevalence of depression among medical students ranging from 27.2% to 32.9% [16]. Ibrahim et al., also found that depression rates among university students, including medical students, were significantly higher compared to the general population [29]. The prevalence obtained in this study is higher than the 42% obtained among medical students at Azhar University in Egypt [28]. The high prevalence of depression obtained in this study could be due to the period of data collection as most of the students were either writing or preparing for their final professional exams with untoward academic pressure. It is not impossible that the anxiety and stress accompanying these exams could mimic depression presentation.

The significant association between gender and depression suggests that female medical students are more susceptible to depression, potentially due to additional stressors such as societal pressures and expectations. Female medical students had a significantly higher prevalence of depression compared to males (44.4% vs. 23.8%, p=0.010). This finding mirrors results from studies like Dyrbye et al., who observed that female medical students often reported higher rates of psychological distress and depression compared to their male counterparts [22]. Hope and Henderson, similarly found that female students outside North America were at a higher risk for depression [30], they tend to be more concerned about working hard to secure higher marks in exams, are more competitive and concerned about their academic performance, may exaggerate their sadness, and tend to be less engaging with exercise [31, 32].

The impact of academic factors on depression was evident in the significant relationship between the medical school curriculum and mental health. Participants who reported that the curriculum significantly affected their mental health were more likely to experience depression. This finding supports existing literature that highlights the demanding nature of medical education as a contributing factor to mental health issues. Quek et al., pointed to the intense academic demands of medical education as a major factor for depression in students [33].

This study found a significant association between financial stress and depression (p=0.043). This aligns with findings from Ibrahim et al., who noted that financial difficulties were a common source of stress that contributed to depression among university students, including medical students [29]. Lifestyle factors such as dietary habits and sleep quality were found to be related to depression, with poor dietary habits and sleep quality contributing to higher rates of depression. These findings reinforce the importance of maintaining a healthy lifestyle to support mental well-being.

Interestingly, no significant relationship was found between academic pressure and depression (p=0.670), even though the majority of participants identified academic pressure as a major stressor. This may suggest that while academic pressure is pervasive, other factors such as personal relationships and financial stress may play a larger role in contributing to depression. Other studies such as Dyrbye et al. have consistently reported a strong link between academic stress and depression among medical students [22]. This discrepancy could be due to differences in the support systems available to students in various contexts. Physical exercise was not significantly associated with depression (p=0.645), whereas studies like Quek et al., found that regular physical exercise was significantly protective against depression among medical students [33]. A significant relationship was found between dietary habits and depression (p=0.010), which is less frequently highlighted in the literature. While some studies, such as those by Hope and Henderson, focus on more well-known contributors like academic pressure and sleep [30]. Sleep quality showed a borderline association with depression (p=0.092), while in other research, such as Rotenstein et al., poor sleep quality was consistently identified as a strong predictor of depression [16].

The incidence of suicidal ideation among medical students in the present study was 15.0%. Medical students have a higher risk of suicidal ideation, suicide, burnout, and a lower quality of life than age-matched populations [34, 35, 36]. The magnitude of suicide ideation among medical students in 13 Western and non-Western countries ranged from 1.8% to 53.6% [37]. The prevalence of suicide ideation among medical students in South Africa was 32.3% [38]. In community-based studies, the rate of suicidal ideation is generally lower, often reported at around 3-5%, which further highlights that 15% in this study is on the higher side, possibly linked to the high incidence of depression (68.1%) in the study population [39].

Conclusion

The study reveals a high prevalence of depression among the medical students. A variety of risk factors identified in this study included socio-demographic, academic, and lifestyle factors. The findings of this study point to an urgent need for more research into the causes as well as early diagnosis of depression using standardized tools. The need of making psychiatric services, counseling as well as support services available to susceptible students is highly imperative.

Conflicts of Interest

None

Appreciations

Special appreciations to Prof.  Gabriel Ogun, the Provost of the School of Medicine & Allied Health Sciences for promotion of mental health and unflinching supports to medical students with mental health problems.

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