Psychiatric comorbidities and sleep quality in Epilepsy: A Cross-sectional study in tribal population of Mayurbhanj district of Odisha

Abstract

Objective:

Our primary objective is to determine the prevalence of various psychiatric comorbidities in patients with epilepsy (PWE) and to assess sleep quality in PWE.

Methods:

Present study was a hospital based cross sectional study conducted over 2 months (January and February of 2022) that included 242 tribal patients from outdoor patient department in Mayurbhanj district of Odisha. Consecutive sampling was conducted. The patients fulfilling the inclusion and exclusion criteria were first assessed using a semi structured proforma for the socio-demographic data. The International Classification of Epilepsies (ILAE-1981) was used to classify seizure types. We used the Mini International Neuropsychiatric Interview (MINI 7.0.2) to assess psychiatric co-morbidity in all subjects. Hamilton anxiety scale (HAM-A), Hamilton rating scale for depression (HAM-D), brief psychiatric rating scale (BRPS), and young mania rating scale (YMRS) was applied accordingly depending on the psychiatric symptoms. Pittsburg sleep quality inventory (PSQI) was used to measure the sleep quality. Adherence in this study was determined by using a simple yes/no question that if the patient was taking the prescribed medications in the recommended dose, frequency and duration as prescribed by the mental health professional. Non-adherence refers to not taking the prescribed anti-epileptic drug and/or psychotropics if any as per recommended dose and duration as prescribed by the health care provider.

Results:

The prevalence of major depressive disorder, generalized anxiety disorder, psychotic disorder, and panic disorder was 18.2%, 16.1%, 15.7%, 1.2%, respectively. Hypomania and mania constituted 0.8% and 1.7% of the sample respectively. Suicidality with no other psychiatric illness was seen 2.1% of the population. PSQI scores among PWE had positive correlation with age (r = 0.171, P = 0.008), BPRS scores (r = 0.177, P = 0.006), HAM-D scores (r = 0.436, P = 0.000), and HAM-A scores (r = 0.228, P = 0.000), while negative correlation with duration since last seizure (r = −0.142, P = 0.027). Median age (P = 0.028), median duration of illness (0.009), HAM-D (P = 0.034), and PSQI scores (P = 0.004) were higher among non-adherent PWE. Duration since last seizure had higher median value among adherent PWE (P = 0.000). There is significant association of compliance with side effects (P = 0.020) and number of seizures per year (P = 0.016).

Conclusion:

Depressive and anxiety disorders are more common psychiatric co-morbidities tribal PWE. When compared to unselected epilepsy patients, tribal PWE had higher prevalence of psychotic spectrum disorders, while lower prevalence of manic and hypomanic disorders. Sleep disturbance is an important indicator for poor maintenance of epilepsy. Non-adherence is associated with poor control of seizure and longer duration of illness. Tribal PWE with depression and poor sleep also have poor adherence. Improving adherence and sleep quality may improve the seizure control. Also, treatment of psychiatric co-morbidities may help in better seizure control. Non association of adherence and unemployment suggests that finance was not a barrier for adherence to treatment in tribal population of Mayurbhanj as most of the PWE were being treated under district mental health program (DMHP).

INTRODUCTION

Epilepsy is a brain disorder that has susceptibility to produce multiple seizures followed by cognitive, psychosocial, and neurobiological consequences.[1] Epilepsy is associated with various psychiatric comorbidities such as anxiety, psychosis and mood disorders and their prevalence in epilepsy is more than or equal to two to three fold as compared to the general population.[2,3,4] The lifetime prevalence of mental health disorder is 35.5% among epileptic patients.[5] Although certain chronic illnesses such as asthma, diabetes or cancer have markedly altered lifestyle and functionality, epilepsy has more substantial psychiatric co-morbidity.[6] Epilepsy consists of a heterogeneous population and this overlap with heterogeneous psychiatric illnesses may obstruct a broad diagnostic approach. How the clinical characteristics of epilepsy may be etiologically related to psychiatric symptoms is yet to be explored.

India has 8.6% of total tribal population that is one third of world’s tribal population. Regarding healthcare there is a huge gap between tribal and non-tribal population. Almost half of scheduled tribes are living in poverty. It has been observed that the disease burden with respect to mental health and addictions is almost three to four times higher in tribal population.[7] It was seen that 5% out of 5007 ST population from West Godavari in Andhra Pradesh had common mental illnesses (CMIs). CMIs consisted of stress, depression, suicidal risk, and anxiety. Female gender had higher prevalence of CMIs. Age, education, and marital status were strongly associated with CMIs.[8] Idu Mishmi of Arunachal Pradesh (Roing and Anini districts) had higher prevalence of suicide that is 14.2% as compared to general population (0.4-4.2%). Mostly it was associated with psychiatric illnesses like depression, alcoholism, anxiety, and eating disorders.[9] The urban population of Bhutias of Sikkim had more perceived stress as compared to rural community.[10] In tribal women severity of depression and stress was higher than non-tribal women.[11]

It is very evident that the tribal population of India is one of the most neglected groups and has higher mental health gap compared to the general population. It is extremely essential to explore the prevalence and correlates of psychiatric co-morbidities of epilepsy in this group.

The presence of various psychiatric co-morbidities in patients with epilepsy (PWE) leads to poor adherence to treatment, and thereby leading to inadequate seizure control. These factors may lead to the poor quality of life and high care giver burden, thereby leading to increase in the global burden of epilepsy. Sleep deprivation and poor sleep quality is another contributing factor for precipitation of epilepsy. It is crucial to explore the various factors affecting adherence in PWE having psychiatric co-morbidities and how sleep comes into play. There are many factors that affect seizure frequency in epilepsy such as sleep deprivation, stress, use of certain drugs and alcohol, dehydration, hypoglycemia, electrolyte imbalance, stroke, infection, and so on. We have focused on psychiatric co-morbidities and sleep disorders in patients with epilepsy because of their high prevalence, bi-directional relationship, chronic course of illness, and underdiagnosis in clinical practice.

There are very few studies in India focusing on psychiatric co-morbidities of epilepsy and close to none focusing on tribal population of India. Tribal population in India is the most understudied group when it comes to mental health. As they are one of the most vulnerable groups to develop mental health related issues, it will be interesting to find out the prevalence and severity of various mental disorders, as well as sleep quality associated with epilepsy. This study will also focus on the various sociodemographic and clinical correlates of adherence to treatment in tribal PWE. It is the need of the hour to highlight how different is the prevalence of psychiatric co-morbidity in epilepsy within the tribal population as they are geographically isolated and have different cultural beliefs. In addition to that their awareness about the illness and understanding of the cause of the illness may affect their adherence and treatment seeking behavior. Hence it is essential to understand all the factors that affect the occurrence and management of various psychiatric comorbidities in epilepsy in this group. This will help us to appreciate the barriers to treatment and pave way for future research in relation to addressing these barriers. Our study is going to add to the small literature that is available on tribal populations of India.

METHODOLOGY

Our primary objective was to determine the prevalence of various psychiatric comorbidities in PWE in the tribal population. The secondary objective of this study was to assess sleep quality in PWE, to evaluate the correlation of sleep quality as measured by PSQI with the severity of psychiatric comorbidities in PWE of tribal community and clinical variables of epilepsy. Similarly, correlations of treatment adherence with severity of psychiatric co-morbidities, clinical variables of seizure and response to treatment were also studied.

This study was a hospital based cross-sectional study. A sample of 242 was included for the study after applying inclusion and exclusion criteria that was achieved in 2 months in the year 2022. Sample size calculation was conducted based on prevalence of psychiatric comorbidities in previous studies.[12] Sample size of 200 could achieve a confidence interval of 90% and level of significance 0.05. Considering an attrition rate of 25%, 240 patients were recruited for the study. Patients belonging to tribal community of Mayurbhanj between ages 18 to 60 years with established diagnosis of epilepsy using ILAE classification giving written consent/guardians or nominated representatives giving written consent (in cases where the patients were too ill to understand the process of informed consent and give an informed choice) were included. While obtaining the consent of guardians, they were explained the research purpose, aim, methodology, risks, and benefits regarding the study. In addition, we explained how the data would be collected, stored and it was ensured that confidentiality would be maintained. They were explained in the local language and were given the opportunity to ask for clarification. They were also informed about their right to withdraw from the study. This process was approved by the IERB.

Cases with mental retardation, major neurological illnesses, co-morbid chronic medical conditions such as asthma, chronic obstructive pulmonary disease, chronic liver disease, chronic renal failure, coronary artery disease, and so on. were excluded to adjust for confounding. Patients with secondary seizures due to any brain pathology (tumor/infection/metabolic encephalopathy) were excluded. Patients admitted in high dependency unit and intensive care unit were excluded. Patients with active substance dependence as per ICD 10 DCR criteria except nicotine/caffeine were excluded. Patients who had never received any anti-epileptic medication were excluded as drug naïve patients cannot be studied for adherence.

As per 2011 census, the tribal community of Mayurbhanj constitutes 58.7% of the total population. The major tribes of Mayurbhanj are the Santals, Kolha, Bathudi, and Bhumija. 49.4% of total tribal population of Mayurbhanj are male and 50.6% are female. 97.3% of the tribal population live in rural setting.[13]

Information was obtained through direct clinical interviews as well as going through the case files. We used a semi-structured proforma to collect socio-demographic details. For PWE clinical variables such as seizure duration, last seizure, type and frequency of seizures, type of antiepileptics (AED), seizure control and family history of psychiatric disorder was ascertained from medical notes supplemented by interview of subjects and their relatives.

The international classification of epilepsies(ILAE-2017)[14] were used to classify seizure types. We used the mini international neuropsychiatric interview (MINI 7.0.2) to assess psychiatric co-morbidity in all subjects. The Hamilton anxiety scale (HAM-A),[15] The Hamilton rating scale for depression (HAM-D),[16] brief psychiatric rating scale (BRPS)[17] and young Mania rating scale (YMRS)[18] were applied accordingly depending on the psychiatric symptoms. Pittsburg sleep quality Inventory (PSQI)[19] was used to measure the sleep quality. Adherence was defined as the extent to which the patient corresponds to the prescribed recommendations from a mental health professional.[20] Here, in our study adherence referred to adherence to both anti-epileptics and/or psychotropic drugs in the recommended dose, frequency and duration as prescribed by the mental health professional.

RESULTS

Table 1: Descriptive statistics were used to determine the distribution of sample across gender, education, employment status, type of seizure, number of seizures per year and per month, co-morbid medical illness, adherence, side effects, family history, and suicide attempt. Out of 242 patients with epilepsy 48.3% were male and 51.7% were female. 1.2% were uneducated while 76% studies up to 10^th grade and 22.7% above 10^th grade. 42.1% were employed while 57.9% did not have employment. The mean age of the sample was 30.4 ± 10.7. 6.2% out of 242 patients had complex partial seizure while 93.8% had generalized seizure. 58.3% had more than 1 to 10 seizures per year while 41.7% had more than 10 seizures per year. The median number of seizures of the tribal population was 5 per year. 66.5% had less than or equal to 1 seizure per month while 33.5% had more than 1 seizure per month. 88.4% had no history of medical illness and 11.6% had co morbid medical illness. As many as 75.2% had good adherence while 24.8% did not have adherence. 86% had no side effects while 14% had side effects from anti-epileptic drugs. 33.9% were on mono therapy, 50% on dual AED, 8.7% on triple therapy and 7.4% on poly therapy. 13.6% had family history of mental illness and 7.4% had family history of medical illness. 14.5% had suicidal attempt. Mean duration of illness was 12.2 ± 9.8 years and mean age of onset of seizure was 18.2 ± 12.3 years. Mean duration since last seizure was 108.89 ± 12.3 days. Out of 242 patients with epilepsy 44.2% had no psychiatric co-morbidities. The prevalence of major depressive disorder and generalized anxiety disorder was 18.2% and 16.1% in our study. Psychotic disorder was seen in 15.7% while panic disorder was seen in 1.2% of the sample. Hypomania and mania constituted 0.8% and 1.7% of the sample, respectively. Suicidality with no other psychiatric illness was seen 2.1% of the population.

Table 1.

Socio-demographic, clinical variables and psychiatric co-morbidities in PWE

	Patients with epilepsy n=242
Socio-demographic variables
Gender	Male=117 (48.3%) Female=125 (51.7%)
Education	Uneducated=3 (1.2%) Up to matric=184 (76%) Above matric=55 (22.7%)
Occupation	Employed=102 (42.1%) Unemployed=140 (57.9%)
Marital status	Divorced=2 (0.8%) Married=102 (42.1%) Single=138 (57%)
Type of family	Joint=96 (39.7%) Nuclear=146 (60.3%)
Age	30.4±10.7
Clinical variables
Seizure type	CPS=15 (6.2%) GTCS=227 (93.8%)
Number of seizures per year	>1–10/Y=141 (58.3%) >10/Y=101 (41.7%) Median: 5 per year
Number of seizures per month	≤1/MON=161 (66.5%) >1/MON=81 (33.5%)
History of medical illness	No=214 (88.4%) Yes=28 (11.6%)
Adherence	No=60 (24.8%) Yes=182 (75.2%)
Side effects	No=208 (86%) Yes=34 (14%)
Number of Anti-epileptic drugs	Mono=82 (33.9%) Dual=121 (50%) Triple=21 (8.7%) Poly=18 (7.4%)
Family h/o mental illness	No=209 (86.4%) Yes=33 (13.6%)
Family h/o medical illness	No=200 (82.6%) Yes=42 (17.4%)
Suicide	No=207 (85.5%) Yes=35 (14.5%)
Duration of illness (in years)	12.2 (9.8)
Duration since last seizure (in days)	108.89 (202.80)
Age of onset	18.2 (12.3)
Psychiatric co-morbidity
No Comorbidity	107 (44.2%)
GAD	39 (16.1%)
MDD	44 (18.2%)
Panic Disorder	3 (1.2%)
Hypomania	2 (0.8%)
Mania	4 (1.7%)
Psychotic Disorder	38 (15.7%)
Suicidality	5 (2.1%)

GAD=Generalized anxiety disorder, MDD=Major depressive disorder, PWE=Patients with epilepsy

Table 2 PSQI scores among PWE had positive correlation with age (P = 0.008), BPRS scores (0.006), HAM-D scores (P < 0.001), and HAM-A scores (P < 0.001) as statistically significant. PSQI scores had negative correlation with duration since last seizure (P = 0.027) which was statistically significant. Age at onset, duration of illness and YMRS scores did not show statistically significant correlation with PSQI scores. Spearman correlation was used to find out the correlations as the data represented non-parametric data.

Table 2.

Clinical Correlates of PSQI Scores In PWE

Clinical variables	Correlation coefficient	P
Age	0.171	0.008**
Duration since last seizure	−0.142	0.027*
Age at onset of seizure	0.88	0.173
Duration of seizure disorder	0.12	0.850
BPRS	0.177	0.006**
YMRS	−0.041	0.529
HAM-D	0.436	<0.001**
HAM-A	0.228	<0.001**

**Significant at 0.01. *Significant at 0.05. BPRS=Brief Psychiatric Rating Scale, YMRS=Youngs Mania Rating Scale, HAM-D=Hamilton Rating Scale for Depression, HAM-A=Hamilton Anxiety Scale, PSQI=Pittsburg sleep quality Inventory, PWE=Patients with epilepsy

Table 3: Independent samples Mann-Whitney U test was used to compare the mean-rank values of various clinical variables between compliant/adherent and non-compliant/non-adherent patients with epilepsy. Median age was higher among non-compliant PWE (P = 0.028). Median duration of illness was higher among non-compliant patients (0.009). Duration since last seizure had higher median value among compliant PWE (P < 0.001). Higher median HAM-D (P = 0.034) and PSQI scores (P = 0.004) were seen among non-compliant patients. There was no significant difference between the two groups with respect to age at onset, BPRS, YMRS, and HAM-A scores.

Table 3.

Comparison of various clinical variables with respect to adherence

Variables	Adherence–YES n=182	Adherence-No n=60	P
Age	27	30	0.028*
Duration of seizure disorder	10	12.5	0.009*
Duration since last seizure	50	6	<0.001**
Age at onset	16	14	0.492
BPRS	20	20	0.211
YMRS	1	1	0.356
HAM-A	4	2	0.498
HAM-D	3	4	0.034*
PSQI	2.47	4.41	0.004*

**Significant at 0.01. *Significant at 0.05. Independent samples Mann-Whitney U test used. BPRS=Brief Psychiatric Rating Scale, YMRS=Youngs Mania Rating Scale, HAM-D=Hamilton Rating Scale for Depression, HAM-A=Hamilton Anxiety Scale, PSQI=Pittsburg sleep quality Inventory

Table 4: Binary logistic regression analysis of PWE with adherence vs. non adherence to medications was performed. Entered variables were gender, occupation, domicile, type of family, side effect, type of seizure, number of seizures per year and history of other medical illnesses. Adherence was associated with no side-effect (OR = 4.017, P = 0.029) and more than 10 seizures per year (OR = 2.065, P = 0.010).

Table 4.

Binary logistic regression analysis of PWE with adherence vs. non-adherence to AED and psychotropics

Explanatory variables	ß	P	Odds ratio	95% CI
Gender	−.317	0.346	0.728	0.376–1.409
Occupation	0.402	0.240	1.495	0.765–2.921
Domicile	−.174	0.664	0.840	0.382–1.847
Type of family	−.380	0.233	0.684	0.366–1.276
Side effect	1.391	0.029*	4.017	1.153–13.995
Type of seizure	1.013	0.219	2.755	0.548–13.858
Number of seizures per year	0.725	0.010*	2.065	1.116–3.822
History of other medical illness	0.190	0.719	1.209	0.430–3.399

*Significant at P=0.05. PWE=Patients with epilepsy, AED=Antiepileptics

Table 5: Chi-square test was used to compare adherent and non-adherent PWE across various clinical and socio-demographic variables. There was no significant difference between two groups with respect to number of anti-epileptic drugs (P = 0.161), and education (P = 0.582).

Table 5.

Comparison of sociodemographic and clinical variables with respect to adherence using Chi-square test

Variables	Adherence-Yes	Adherence-No	χ 2	df	P
Anti-epileptic drugs
Mono	56 (23.14%)	26 (10.74%)	5.158	3	0.161
Dual	96 (39.66%)	25 (10.33%)
Triple	18 (7.43%)	3 (1.23%)
Poly	12 (4.95%)	6 (2.47%)
Education
Uneducated	3 (1.2%)	0 (0)	1.084	2	0.582
Up to matric	137 (56.6%)	47 (19.4%)
Above matric	42 (17.4%)	13 (5.37%)

**Significant at 0.01. Chi Square test is used

DISCUSSION

In our study 18.2% PWE had major depressive disorder. Studies have shown that the prevalence of depression among seizure free epilepsy patients is similar to that in general population,[21] whereas the prevalence of depression is raised in unselected epilepsy patients (17%–22%) similar to our finding[5] and it is as high as 55% among AED resistant epilepsy.[22] One meta-analysis has shown that prevalence of depression is 23.1% among epileptic patients and the risk is 2.7 higher than the general population.[23] In this study GAD was seen in 16.1% and panic disorder was seen in 1.2% of 242 tribal PWE. In one cohort study it was seen that incidence rate of anxiety illnesses is higher among epilepsy population in comparison to controls and also it is raised in 3 years preceding the diagnosis of epilepsy.[24] Lifetime prevalence of anxiety disorders and current prevalence of anxiety disorders among epileptics as per a systematic review was 15.6% and 6.3%, respectively.[25] Another meta-analysis suggested that pooled prevalence of various anxiety illnesses was 20.2% and GAD (Generalized anxiety disorders) were the most common.[26] Our study when compared with above mentioned studies suggests that there is no difference in prevalence of co-morbid depression and anxiety disorders between tribal PWE and unselected epilepsy patients.

Psychotic disorder was seen in 15.7% while hypomania and mania constituted 0.8% and 1.7% of the sample respectively. When compared to anxiety and mood disorders, psychotic disorders are less common among epilepsy patients however they are more associated with morbidity and mortality. Psychotic disorders are seven times more prevalent in epilepsy than general population.[27] In unselected epilepsy samples prevalence of non-organic psychoses is almost equal to 4% to 5%,[28,29] however in hospital based samples it was much higher.[30] A meta-analysis has shown that psychoses is most prevalent in temporal lobe epilepsy (TLE) that is around 7%.[31] There is strong association between psychoses and epilepsy as suggested by family history of both being potential risk factors.[27] It has also been suggested by two retrospective cohort studies that schizophrenic patients have 2–3 times higher risk of developing epilepsy.[32] Apart from depression various other mood disorders such as bipolar affective disorders, dysthymia are also present in epileptic patients, however they are under-diagnosed and under-treated.[33] It has been seen in one US survey that prevalence of manic symptoms in epileptic patients is around 12.2% which is higher than the general population. Hence there could be an association between epilepsy and bipolar affective disorders.[34] In drug resistant epilepsy, it has been observed that the prevalence of post-ictal mania/hypomania is around 22%.[35] Our study shows that the prevalence of psychosis in epilepsy is higher among tribal population when compared to unselected epilepsy patients in other studies that is more than two times. We also found that tribal population of Mayurbhanj have lower prevalence of manic and hypomanic symptoms in epilepsy as compared to general PWE.

14.5% of PWE had suicidal attempt. Suicidality with no other psychiatric illness was seen in 2.1% of the population in this study. The prevalence of suicidal attempts and completed suicide is in the range 5 to 14.3% in patients with epilepsy that is much higher than general population that is 1%–4.6%.[36] Suicide ideation in patients with epilepsy has a 2 week prevalence rate of 12.7%.[37] Suicide is one of the causes for premature death in epileptic patients that is almost equal to 5%.[38] In one study it was seen that the incidence of suicidal attempts was much higher among epileptics than controls.[39] Most studies were in line with our finding with respect to suicidal attempt in epileptic patients suggesting similar results between tribal and unselected PWE.

PSQI scores among PWE had positive correlation with BPRS scores, HAM-D scores, and HAM-A scores that were statistically significant. This implies that the more severe the psychiatric illnesses (psychotic spectrum, depression, anxiety) in tribal PWE, the lower the quality of sleep. However, YMRS scores did not show significant correlation with PSQI which may be due to a smaller number of patients with co-morbid mania and hypomania.

In one study it was seen that PWE had more sleep disturbances as compared to controls and half of the PWE had their last seizure more than 1 year ago.[40] As per this study, sleep disturbances in PWE occurred irrespective of severity and frequency of the seizures.[40] However, in our study, PSQI scores had negative correlation with duration since last seizure which suggested that better seizure control is associated with better sleep quality among tribal population. Another study suggested association between poor seizure control and sleep disturbance in PWE like our finding.[41,42,43] Age did not influence sleep disturbance among PWE[40] unlike our finding where age was positively correlated to sleep disturbance. It is known that ageing does not inherently cause sleep disturbance, however medical and psychiatric co-morbidities that occur with advancing age can cause sleep disturbance.[44] Similarly, in our study among tribal population, we could assume that presence of epilepsy may be one of the factors responsible for association between sleep disturbance and age. Age at onset of seizure and duration of epileptic disorder did not show statistically significant correlation with PSQI scores.

HAM-D and PSQI scores were higher in non- adherent PWE patients than adherent patients among tribal population. This implies that tribal patients with epilepsy who had more depressive symptoms and poor sleep quality did not take medicines. Depression had negative correlation with adherence in one of the studies that was also seen in our study.[45] This implies that severe depression can lead to poor adherence to antiepileptic medications and vice versa. Additionally, we found out that BPRS, YMRS, and HAM-A scores had no significant difference between adherent and non-adherent patients. And psychiatric co-morbidity did not have any association with adherence in our study. This implies that presence of psychiatric illness in tribal group may not affect the adherence to medications. Severity in psychotic illnesses, anxiety spectrum disorder, and manic or hypomanic illness did not affect the adherence to medication as that seen with depression. This might be an incidental finding and more significant results can be obtained with bigger sample size. More explorative studies are required to understand the relationship of various psychiatric illnesses and their severity with medication adherence in epilepsy.

The median age and duration of seizure disorder were higher in non-adherent PWE than adherent patients among tribal population. There was also significant association of adherence with side effects and number of seizures per year however no association with number seizures in last 1 month. In other studies, it was seen that non adherence was significantly associated with seizure control[46,47] and side effects of AED similar to our finding.[48,49] In one of the review articles, it was seen that older age was also associated with non-adherence similar to our finding.[50] However another study suggested age and side effects were not associated to adherence contrary to our findings.[51] Thus, we can conclude from our study that older people, poor seizure control and those with longer duration of epileptic disorder were reluctant to adhere to therapy. This can be explained by the fact that disease burden in form of chronicity of illness and advancing age can affect adherence to treatment in the long run. There should be measures at place such as good family support, easy accessibility to medication, lower pill burden, directly observed pharmacotherapy and psychoeducation to combat the barriers to adherence.

One review stated that there was association of adherence with marital status, level of education and absence of co-morbidity.[50] In our study there was no association of adherence with number of anti-epileptic drugs, education, and occupation. Education and employment status was associated to adherence as per one review article which was not in accordance to our study.[49] In our study, employment status of the tribal population had no significant effect on adherence suggesting finance was not a barrier to adherence. One of the reasons for the same could be availability of affordable medicines in the district of Mayurbhanj as all patients were being treated under the DMHP (District mental health program). District Mental Health Program has helped decentralize mental health services. One of its major objectives is to provide primary mental health care services followed by integration of mental health with general health care services as well as early diagnosis and management of mental illnesses.[52] DMHP consists of multidisciplinary team including a psychiatrist, clinical psychologist, psycho-social worker, community nurse, monitoring and evaluation officer, case register assistant and ward assistant.[52] Each member has particular roles and responsibilities which may vary from state to state. The nurses and psychiatric social workers provide care through home visits; thus, taking healthcare services to doorstep that helps in regular follow-up and adherence to treatment.[52]

Interestingly, number of pills did not affect adherence as can be seen by the fact that number of antiepileptic drugs did not affect adherence. In one article it was found that mono-therapy had better adherence than poly-therapy which contrasted with our study.[49,53] This suggests that pill burden was not a barrier for adherence in tribal community of Mayurbhanj. The reason for the same could be multifactorial including good psychoeducation, awareness regarding adherence to treatment, regular follow-up, good community outreach programs, good patient-doctor relationship, and so on. Qualitative analysis can help in exploring the reasons for good adherence despite polypharmacy and pill burden.

Gender did not have any association with adherence in our study. Similarly finding was seen with respect to gender in a previous study.[51] Thus, both male and female patients in tribal community had similar adherence to AED like that of unselected epilepsy patients. Even though the duration of illness affected the adherence to treatment in the tribal population as discussed earlier, however age of onset of seizure disorder did not affect the same. The median age of onset was higher among PWE who were adherent as compared to non-adherent PWE but it was not statistically significant. This finding suggests that a bigger sample may be required to establish significance.

Limitations

Ours is a cross-sectional study. Adherence was not assessed using any tool that would have made the assessment more objective. Quality of life and functional outcome has not been assessed.

CONCLUSION AND FUTURE DIRECTIONS

Psychiatric illnesses are significantly co-occurring with seizure disorder. Depressive and anxiety disorders are more common psychiatric co-morbidities tribal PWE as compared to other psychiatric illnesses. When compared to unselected epilepsy patients, tribal PWE had higher prevalence of psychotic spectrum disorders, while lower prevalence of manic and hypomanic disorders. It is essential that patients with epilepsy should be actively screened for psychiatric illnesses so early intervention can be done.

Sleep disturbance is an important indicator for poor maintenance of epileptic disorders. Sleep is more affected in more severe psychiatric illnesses in tribal PWE. Non-adherence is associated with poor control of seizure and longer duration of illness. Tribal PWE with depression and poor sleep also have poor adherence. Improving adherence and sleep quality may improve the seizure control. Also, treatment of psychiatric co-morbidities may help in better seizure control.

We also found out that pill burden, female gender and unemployment were not barriers for adherence among tribal population. Non association of adherence and unemployment suggests that finance was not a barrier for adherence to treatment in tribal population of Mayurbhanj as most of the PWE were being treated under DMHP.

Further study can be conducted to see the correlation of different types of seizure with different types of psychiatric co-morbidities. Brain imaging studies can be used to see how PWE with psychiatric comorbidities are different from those without psychiatric co-morbidities. Further analysis may be conducted to see the effect of various AEDs on psychiatric illnesses in PWE. Also, further research can be conducted to identify the barriers to treatment of psychiatric illnesses in PWE.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.