In this study, the proportion of low anti-epileptic drug adherence was found to be 20.2%. This proportion was lower when compare with the study done in Jimma, Dilla and India [15, 22, 23]. But Dessie comprehensive specialized hospital low medication adherence proportion was higher than study conducted in south west Ethiopia [18]. These variations might be due to methodological differences among studies and dissimilarities in socio-cultural, health service utilization, and economical variations among study participants.
In this study, the proportion of medium antiepileptic drug adherence was found to be 30.8%. This Dessie comprehensive specialized hospital proportion of medium AED adherence was lower than a study conducted in South West Ethiopia, Nigeria [18, 25]. But this proportion was higher than study conduct in Haryana India [26]. This discrepancy might be due to difference in socio-demographic status of study participants, difference in sample size, number of prescribed medications, side effects and frequency of medication, severity of the disease.
In accordance with this study finding, the medium medication adherence among epileptic patients who were farmer and daily laborer were 1.008 and 1.039 times higher than those who were government employ. The relationship between medium medication adherence and occupation status of the patient was also shown in similar studies done in Saudi Arabia [27]. The patients who were farmer and daily laborers were less educated so that they seem to be less compliant, which implies less knowledge about the drug effects on the life style may affect the patients compliant nature.
The study result showed that epileptic patients’ with age category 18–27 has a statistically significant association with the moderate anti-epileptic drug adherence. The medium medication adherence was found to be 84% times highly protective than for epileptic patient whose age category is equal and above 48 years. This result is supported by a study done in Egypt [28]. This could be justified by the fact that when age increases, patients would have more difficulty in following instructions owing to decreased cognitive functions or other physical difficulties such as problems in swallowing medications, so adherence might be decreased with aging.
The medium anti-epileptic drug adherences among patient who are rural residents are 1.031 times higher than those who are urban resident. This finding is in line with a study done in the Nigeria [29]. The residents of rural communities are at risk of having less exposure to basic health information, such as the necessity of preventive medicine. Without access to this knowledge, rural patients are more likely to develop unhealthy behaviors which are likely to result in negative health outcomes, like chronic health conditions.
The other independent predictor which had a very strong association with medium medication adherence was seizure with in the past one year. The result showed that the medium medication adherence in patient with seizure with in past one year were 1.305 times higher than those who have n’t seizure with in the past one year. This finding is supported by a studies done in Ethiopia [30]. This can be explained by the fact that longer seizure free years would make patients to be more adherent to their medications possibly by increasing patients’ belief on medication effectiveness and this is in line with other studies.
With regard to seizure with in past one year, the study result showed that the low medication adherence for patient was 1.033 times higher than those patients who are free of seizure with in past one year. This result is in line with the study done in Aksum, Saudi Arabia, and India [12, 31, 32]. This might be related to patient’s perception of the treatment and seizure control. Patients may perceive that the treatment is not working if they experience a single seizure attack, and may discontinue the medication or they might take more than the dose prescribed.
In accordance with this study finding, the low medication adherence among patients with comorbidity was found to be 36.389 times more likely to low adherence of AED when compared to those patients who had no comorbidity. The relationship between comorbidity and AED adherence was also shown in similar studies done in Aksum, Ethiopia, and Pakistan [31, 33, 34]. This could be explained that patients with comorbidity are more likely to have multiple drugs. Thus, they could be reluctant to take all drugs properly. Moreover, the risk of adverse drug events is increased in patients with comorbidities which can also negatively affect the adherence rate.
The other independent predictor which had a very strong association with low medication adherence was adverse effect experiences with in past one year. The result showed that low medication adherence by the patient with adverse effect experiences with in past one year was 3.938 times higher than those who haven’t adverse effect experiences with in past one year. This finding is supported by different studies done in Ethiopia, and India [14, 35, 36]. This is possibly explained by the fact that anti-epileptic medications side effects can have a potential to affect both the physical and psychological states of people with epilepsy. People may also lack trust towards medications while there is serious side effect and they may stop their medication intake.
The other independent predictor which had a very strong association with low medication adherence is duration of drug. The result showed that the low medication adherence by patient who has duration of drug 2–5 years were 56.745 times higher than those who have drug duration of above 11 years. This finding is supported by different studies done in Ethiopia [22, 36]. This could be justified by the fact that people with epilepsy often show more concern and commitment towards their treatment as soon as they start first and diminish later. They also argued that anti-epileptic medication is not freely accessible in different countries and people might not afford to purchase their medication for longer duration.