Epilepsy is a disease of the brain defined by at least two unprovoked (or reflex) Seizures occurring within > 24 h apart; one unprovoked (or reflex) seizure and a probability of further seizures similar to the general recurrence risk (at least 60%) after two unprovoked seizures, occurring over the next 10 years [1]. It is a common neurological condition characterized by recurrent seizures and abnormal electrical activity in the brain that causes an involuntary change in body movement or function, sensation, awareness, or behavior [2]. More than 80% of people with epilepsy live in developing countries, and a majority of them do not have recourse to any effective treatment [3].

Depression is highly prevalent in the patient with epilepsy and is the most frequent comorbid psychiatric problem [4]. According to Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), depressive disorder is defined as at least one of the symptoms, either depressed mood or loss of interest or pleasure for at least 2 weeks, and includes at least other four symptoms from a list of criteria items, which are severe enough to cause severe distress or impairment in executing important functional roles [5].

Data from population-based studies have revealed a more complex, bidirectional relation between the two disorders, whereby not only are people with epilepsy at greater risk of developing depression but also people with depression are at greater risk of developing epilepsy. The existing common neurobiological pathogenic mechanisms shared by depressive disorders and epilepsy include neurotransmitter disturbances in the central nervous system such as serotonin, norepinephrine, dopamine, glutamate, and gamma-aminobutyric acid (GABA); endocrine disturbances such as hyperactive hypothalamic pituitary–adrenal axis, resulting in high serum concentrations of cortisol; and inflammatory mechanisms (in particular, interleukin-1β has been found to play a pathogenic role in patients with mood disorders) [6].

Depression is the most frequent psychiatric comorbidity in people with epilepsy with a prevalence rate ranging from 9.5 to 63% [7–12]. It leads to underemployment, lower rates of marriage, and a greater chance of social isolation when compared to counterparts [13, 14]. The high magnitude of depression among people living with epilepsy negatively influences their quality of life and increases suicidal tendency [15, 16]. Factors such as side effects of antiepileptic drugs, perceived stigma, fear of seizures, discrimination, joblessness, lack of social support, increased seizure frequency, and nonadherence to their medication have contributed to inducing depression among epilepsy patients [17, 18].

Despite this burden and consequences, there is a limited literature on the magnitude of depression and associated factors in people with epilepsy in the study area. Therefore, this study was intended to fill the gaps by assessing the prevalence and associated factors of depression among people living with epilepsy. It also helps to integrate mental health service in primary healthcare unit by early diagnosis and timely treatment of comorbid cases.

In this study, the prevalence rate of depression among epilepsy patients was 43.8% (38.9, 48.8%). It is consistent with the study done at the University of Gondar Hospital (45.2%) [25] and Sudan (45.5%) [26].

This finding was lower than the result from the study conducted at the Jimma University Specialized Hospital (49.3%) [19]. Other studies conducted in Nigeria and Gaza stated that depression had been prevalent among 85.5 and 63% of participants, respectively [9, 27] which are very high compared with the current study, and they were almost three times higher in magnitude than that reported in a study done in Canada [11]. This difference might be due to the sociocultural variation and instrument, since those authors used BDI which has items similar to somatic complaints, and this might have led to overestimating the prevalence.

However, the current study’s finding regarding prevalence rate is higher than the report described in Amanuel Mental Specialized Hospital (33.3%) [28], Kenya (16.5%) [29], Iran (9.5%) [8], Thailand (20%) [30], and Greek (22.5%) [31]. These discrepancies might be due to the difference in study participants, method, culture, time, and settings.

In this study, the researchers found a high prevalence of depression among female compared to male respondents which are consistent with the study done in Gaza [9]. However, the study in Nigeria and Ethiopia [19, 27] revealed that no significant relationship between gender and depression in people with epilepsy. The difference is most likely due to diverse methodological approaches, cultural variation, and different instruments they used to measure depression. In general, females faced difficulty in performing normal activities of daily living, and they might face several risks or hardships with regard to reproductive activity and pregnancy. Furthermore, women with epilepsy face difficulty in decision-making with regard to important major life events such as marriage or bearing children. Thus, these consequences might increase depression among females.

With regard to marital status in this study, those who were married were less likely to be depressed compared to those with single status, and having another marital status. This finding was consistent with the previous study in Jimma Ethiopia [19] but inconsistent with other studies in which the authors found no significant difference among different marital statuses [27, 28]. This might be due to marriage-related change of lifestyles because of some kind of guardian-like protective effect of the marital status where adherence to healthy activities is greatly increased—and behaviors leading to health risks are reduced. Moreover, married people also have higher levels of emotional support.

The study has also shown that patients who were not adherent to their medication had depression compared to those who were adherent. This hypothesis is supported by previous studies [19, 25]. The high rates of poor adherence demonstrated in this study are causing concerns, given the consequences of antiepileptic discontinuation. It might be assumed that patients who discontinue medication will be more likely to relapse and have very poor and less control over the disease than those who continue medications.

Moreover, in this study, stigma was associated with depression which is supported by different studies [19, 28]. The previous study conducted in Ethiopia among epilepsy among patients found perceived stigma to be a common problem among people living with epilepsy [32]. This is because people with epilepsy might be overprotected and restricted from doing many activities by their family members, friends, or teachers. Overprotection arising from stigmatization can have severe consequences. Eventually, this stigma shatters a person’s hope and self-esteem leading to negative outcomes related to recovery including depressive symptoms, social avoidance, and a preference for adopting avoidance of coping strategies.

In this particular study, current substance use has a significant association with depression. This result is supported by Epilepsy Action Australia report [33]. Substance use among people taking antiepileptic medications is likely to be more sensitive to the effects of substances. The substance can interfere with the metabolism of these medications and therefore increase the chance of seizures. Some medications can enhance the toxic effects of alcohol, and people can feel severely intoxicated after drinking only a small amount. Skipping a dose, taking extra medication, or altering the time of taking regular antiepileptic medications before drinking will not alter this reaction but may cause additional adverse effects or seizures [33].

In general, the implication of this finding indicates that people living with epilepsy need strong counseling in terms of adherence, by way of creating awareness in the community and addressing misperception issues attached to epilepsy. Collaborative efforts among different stakeholders and clinicians are recommended to bring effective management strategies to neurologic clinics. In addition, generating additional evidence through further research is required.

A limitation of this study was that it was not possible to clarify the cause–effect relationship between depression and epilepsy due to the cross-sectional nature of the study. A prospective study could help to establish clearly whether epilepsy predisposes to depression or a consequence of depression predispose to epilepsy. Another limitation includes recall bias—regarding the duration of illness and substance-use-related factor—which was not assessed by a standard tool.

The finding showed that there is a high prevalence of comorbid depression (43.8%) among epilepsy patients at the AMSH and TAH. The epilepsy-related sociodemographic variables like being female, single, and clinical-related factors including poor medication adherence, current substance use, and perceived stigma were significantly associated with depression. Early recognition of depression symptoms in people with epilepsy should be of great concern for healthcare providers to help them provide appropriate counseling regarding adherence and substance use.