Prevalence and factors associated with depression among medical students in Cameroon: a cross-sectional study

Depression is a mental disorder characterized by loss of interest and pleasure (anhedonia), decreased energy (anergy), feelings of guilt or low self-worth, disturbed sleep and/or appetite, and poor concentration [1]. It is a significant contributor to the global burden of disease and affects people in all countries across the world with a global prevalence of depressive episode of 3.2% [2]. Depressive disorders often start at a young age and often are recurrent throughout life. For these reasons, depression is the leading cause of disability worldwide in terms of total years lost due to disability [2]. The demand for curbing depression and other mental health conditions is thus on the rise globally [2]. Worldwide, it has been demonstrated that 25–90% of medical students are stressed, that is an important determinant of depression [3, 4] leading to a higher prevalence of depression among medical students than general population [5, 6]. Several factors may account for this fact. These include daily life stressors and stressors specific to the tedious learning environment [7]. The potential negative effects of emotional distress on medical students include impairment of functioning in classroom and clinical practice, stress-induced disorders and deteriorating performance. In medical doctors, it has been demonstrated that depression affects patient care leading to increase prescription error [8]. Depression is also associated with higher suicide rates and this may be reason for higher suicide rate in medical professionals than the general population [9]. This is especially true in female medical professionals [10]. Students in extreme stress or depression need serious attention, otherwise inability to cope successfully with the enormous stress of education may lead to a cascade of consequences at both personal and professional levels [11]. To prevent depressive symptoms among medical students, decreased self-esteem, self-perceived medical errors and thus improve on the quality of care given to patients, factors associated with depression in medical training should be identified and appropriately tackled [12]. However, there is scarcity of data in Africa and worse still in Cameroon there is no data on depression and its associated factors among medical students. The aim of this study was to investigate the prevalence and factors associated with depression among preclinical and clinical medical students in Cameroon medical schools and also to evaluate the impact of depression on self-reported academic performance.

To the best of our knowledge this is the first study in Cameroon and the Central African Sub-region to determine the prevalence and factors associated with depressive symptoms among medical students. We also investigated the association between depressive symptoms and self-reported academic performance. In our study about one out of every three medical student is depressed with a considerable number being moderate to severely depressed. Depressive symptoms were significantly associated with chronic disease, major life events, female gender and being a student at the clinical level. However no association was found between depression and self-reported academic performance. Medical training programmes aim to produce knowledgeable, skillful, competent and professional graduates who will render comprehensive healthcare services within their communities. To achieve this aim, most medical programmes are overloaded with facts. This may have unintended negative consequences with respect to students personal mental and physical health [7]. In our study the prevalence of depression was 30.6% and was similar to the global prevalence of 33.0% among university students reported in a systematic review study [14]. Our prevalence was higher than the prevalence of 23.3% reported in a study among undergraduate medical students in Nigeria [17]. In their study, they used a single medical school with a smaller study population. Out of Africa, the variation in the prevalence of depression is even more significant with systematic review studies showing prevalences ranging from 6.0 to 66.5% [18]. Despite this variation in prevalences of depression around the world, studies have consistently showed high prevalence of depression in medical students. Several factors can be advanced for this variation. These include differences in the lengths of training programs, cost of studies, the use of different depression scoring tools and cultural differences around the world [19]. In our study, majority of students presented with mild depression, several presented moderate depression while many presented with moderately severe to severe depression. These findings concur with findings in a study by Kumar and colleagues where 29.8% of participants were scored as normal while 27.8% as mild, 29.3% as moderate, 7.5% as severe, and 6.7% as very severe depression [20]. With regards to the four medical schools included in this study, the prevalence of depression was highest among medical students of the FHS-UB and lowest in the FMPS. This difference was not statistically significant and may be due to the fact that these schools have similar study programs. A higher prevalence was observed in clinical students than pre-clinical students. Previous studies have shown depressive symptoms is not only higher in students in higher levels of studies but also increases as students progress in medical schools [20]. Furthermore depression was significantly associated with the female gender. This fact was supported in study by Dahlin and colleagues in 2005 [21], while other studies have demonstrated marginal increases in depression in female medical students compared to males [20]. Other studies have also reported significant association between depression and the presence of chronic medical conditions and major life events [22]. However, these two are also differential diagnoses of depression. Unlike in our study where depression was not associated with self-reported academic performance, significant association has been reported between depression and self-reported academic performance [22, 23]. In these studies, it was found that depressed students were more likely to have a GPA < 3 than those not depressed. This could be explained by the fact that students with depressive symptoms are less motivated to study or even take care of their patients. This ultimately leads to poor performance.

Despite filling an important gap in the literature, our study does have limitations that are usually associated with an observational design. First, recall bias is limitation of this study as during the filling of the questionnaire some participants may have difficulty recollecting some information leading to inaccuracy in the data entered. However, the sufficient sample size and using a valid score like the PHQ-9 scale to diagnose depression and depressive symptoms of the students increases the validity of the study. Also, when evaluating alcohol consumption we used the cutoff of 21 units/week for men and 14 units/week for women. This cut off is mostly referred to as the limits of low risk drinking. This recommendation was recently changed in January 2016 by Department of Health UK to 14 units/week for both men and women [24].

Depression among medical students in Cameroon is high and is associated with chronic medical condition, major life events, female gender and being a student at the clinical level. The prevalence of provisional depressive disorder and major depressive disorder among medical students was high. Many students presented with moderate to moderately severe depression while a few presented with severe depression.