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ORIGINAL ARTICLE
Year : 2020  |  Volume : 23  |  Issue : 4  |  Page : 215-220

A comparative assessment of health-related quality of life in people with epilepsy and healthy controls in a tertiary hospital in Northwest Nigeria


1 Department of Medicine, Neurology Unit, Benue State University Teaching Hospital, Makurdi, Benue State, Nigeria
2 Department of Medicine, Neurology Unit, Ahmadu Bello University Teaching Hospital, Shika-Zaria, Kaduna State, Nigeria
3 Department of Medicine, Neurology Unit, University College Hospital, Ibadan, Oyo State, Nigeria

Date of Submission21-Nov-2019
Date of Decision23-Jan-2020
Date of Acceptance25-Jan-2020
Date of Web Publication23-Feb-2021

Correspondence Address:
Dr. Emmanuel Uzodinma Iwuozo
Neurology Unit, Department of Medicine, Benue State University Teaching Hospital, P.M.B. 102131, Makurdi, Benue State
Nigeria
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/smj.smj_61_19

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  Abstract 


Introduction: Epilepsy impacts negatively on the health-related quality of life (HRQoL) of affected individuals. Aim: This study compared the HRQoL of patients with epilepsy with age- and-sex matched healthy controls. Materials and Methods: A comparative cross-sectional case–control study was carried out on 206 participants who were ≥18 years. The World Health Organization Quality Of Life instrument was interviewer administered to all the participants. Statistical significance was set at P < 0.05. Results: The mean ages of the patients and controls were 33.4 ± 15.8 and 34.5 ± 11.8 years, respectively. Both the groups consisted of 54 males (52.4%) and 49 females (47.6%) each. The mean HRQoL score of the patients, 65.2 ± 16.4, was significantly lower than that of the controls, 69.6 ± 14.6 (t = −2.043, P = 0.042). Furthermore, people with epilepsy (PWE) had significantly impaired HRQoL in general health (t = −3.826, P = 0.0005), physical health (t = −2.768, P = 0.006), and psychological health (t = −2.266, P = 0.025) domains. However, no significant difference was observed in the social relationship and environmental health domains (t = 0.682, P = 0.496, t = −0.516, P = 0.606), respectively between PWE and controls. Conclusion: Epilepsy significantly impaired the HRQoL of its sufferers compared to healthy controls, especially in the general health, physical health, and psychological health domains. There is therefore the need to ensure comprehensive and evidence-based individualized care to improve their HRQoL and overall outcome.

Keywords: Comparison, epilepsy, health-related quality of life, healthy persons


How to cite this article:
Iwuozo EU, Obiako RO, Ogunniyi A, Abubakar SA. A comparative assessment of health-related quality of life in people with epilepsy and healthy controls in a tertiary hospital in Northwest Nigeria. Sahel Med J 2020;23:215-20

How to cite this URL:
Iwuozo EU, Obiako RO, Ogunniyi A, Abubakar SA. A comparative assessment of health-related quality of life in people with epilepsy and healthy controls in a tertiary hospital in Northwest Nigeria. Sahel Med J [serial online] 2020 [cited 2024 Mar 29];23:215-20. Available from: https://www.smjonline.org/text.asp?2020/23/4/215/310026




  Introduction Top


Epilepsy, a common chronic brain disorder, is defined as an enduring predisposition to generate epileptic seizures and by its neurobiologic, cognitive, psychological, and social consequences.[1] This definition requires the occurrence of at least one epileptic seizure,[1] whereas seizure, on the other hand, is said to be a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.[1] At least 70 million people worldwide are affected by the disease with an estimated 80% of the global burden of epilepsy borne by the developing world.[2] However, most of these areneither even identified nor received modern, effective treatment.[2] The disease has no racial, geographical, or social class boundaries and occurs in both sexes and at all ages, although it is more common among children, adolescence, and elderly.[3] The prevalence rate of epilepsy in the African region ranged from 2.2 to 58 per 1000 population.[3] In Nigeria, the recent prevalence rate ranged from 4.3 to 6.0 per 1000 population.[4],[5]

Clinicians and public health physicians could now use health-related quality of life (HRQoL) to measure the effect of chronic illnesses, treatment, and short- and long-term disabilities on the well-being of the sufferers.[6] The assessment and improvement of HRQoL has been made a public health priority.[7]

Epilepsy is a common neurological condition that impacts HRQoL of affected individuals.[8],[9] Hence, this study assessed the HRQoL of epilepsy patients and compared them with age- and-sex matched healthy controls using the instrument and determined the domain (s) affected in them. We hope that findings from this study will assist clinicians and policymakers to plan preventive strategies toward the overall reduction of the incidence and prevalence of epilepsy in Nigeria as well as help to improve the overall HRQoL of the people with epilepsy (PWE).


  Materials and Methods Top


Study design

This was a comparative cross-sectional case–control study.

Study population

This study was conducted from December 2012 to October 2014 in the Neurology Clinic of the Medical Outpatient Department of Ahmadu Bello University Teaching Hospital (ABUTH), Zaria. ABUTH is a tertiary hospital located in Zaria, Kaduna State, North-Western Nigeria and serves as a major referral center for patients with neurological diseases including epilepsy in North-Western Nigeria and sees over 200 patients with epilepsy yearly.

Sample size determination

The sample size of patients was determined using the Fisher's formula.[10]



Where N = Minimum sample size

Z = the standard normal deviate at 95% confidence level (1.96)

P = prevalence rate of epilepsy in Nigeria put at 6.2%.[11]

d2 = degree of accuracy at 0.05



N = 89.36 approximated to N = 90

With default and nonresponse assumed to be 10% of minimum sample = 9 ≈ 10.

Minimum of 100 patients with epilepsy matched against 100 healthy controls of comparable age and sex, making a total sample size of 200 participants. However, eventually, 206 participants were recruited for the study.

Sampling technique and selection of study participants

A convenience sampling method was used in this study to recruit the patients and controls. Consecutively presenting patients to the Neurology clinic who met the study criteria were selected after obtaining informed consent from them. Epilepsy was diagnosed based on history of at least two unprovoked seizures 24 hours apart corroborated by an eye witness account with supportive abnormal inter-ictal electroencephalography (EEG).[12],[13] The seizures were classified according to the international league against epilepsy classifications of 1981 and 2010.[12],[13]

Consenting patients who were 18 years and above were recruited if they had been on routine follow-up for at least 1 year and came with a caregiver/an eyewitness. Patients with background history of psychiatric disorder, cognitive impairment, substance use disorder, hypertension, diabetes mellitus, and chronic kidney disease were excluded from the study. Controls were consenting healthy persons who were accompanying caregivers of PWE without a history of epilepsy, neurologic disease, or cognitive impairment matched for age and sex with PWE. The investigators conducted general physical examinations and relevant neurologic examination on all the participants, while all the patients had electroencephalography done for them to help support the diagnosis of epilepsy.

Data collection instruments

A structured questionnaire and the WHOQOL-BREF instruments were interviewer administered to all the participants. The WHOQOL-BREF is a generic questionnaire for assessing HRQoL in epilepsy and it is a short version of the WHOQOL-100 instrument. The instrument is useful in large research studies or clinical trials and has been utilized worldwide. The WHOQOL-BREF questionnaire is a reliable and valid instrument.[14] This instrument is generic and not disease specific, as it can be used for assessing HRQoL in patients with chronic diseases such as epilepsy and allows comparisons across patients with different diseases and healthy controls.[15]

The WHOQOL-BREF is a 26-item questionnaire made up of domains and facets. Domains are broad groupings of related facets. The four domain types in the instrument include physical health (7 items), psychological health (6 items), social relations (3 items), and environment (8 items) as well as a general health facet (2 items). A facet is a specific aspect of life for which a coherent definition could be articulated. Of the 26 items of the WHOQOL-BREF, the items on the overall rating of HRQoL and subjective satisfaction with health are not included in the domains but are used to form facet on overall HRQoL and general health.

Each item of the WHOQOL-BREF is rated on a 5-point Likert type scale. Domain scores are scaled in a positive direction (i.e., higher scores denote higher HRQoL). The mean score of items within each domain is used to calculate the mean domain score. After computing the scores, they were transformed linearly to a 0–100 scale using the guidelines by multiplying the mean score by 4 to make it comparable to the scores in WHOQOL-100.[16]

Tool translation/pilot-testing

The questionnaires were translated into Hausa, which is the predominant language understood by a large proportion of the people in the study area by a linguist, this was later translated back into English by another linguist who was blind to the first translation. The back-translated version was reviewed by a panel that included a linguist and a physician that is fluent in written, spoken, and reading comprehension of both English and Hausa languages and knowledgeable about Hausa culture and the uses the questionnaires will be put. The panelists had a consensus that the items on the Hausa translated version reflected the same meaning as the original English version.

To reduce ambiguity, misinterpretation, or misunderstanding of any question in the questionnaire, each version (Hausa and English) was administered independently by the investigators and trained research assistants versed in Hausa language on 10 PWE and 10 healthy controls that were proficient in both English and Hausa language in a pilot study and these subjects were excluded from the final analysis. Selected patients and controls were interviewed in English or Hausa (depending on choice or proficiency) by the investigators assisted by trained research assistants versed in the Hausa language.

Ethical consideration

Ethical approval was obtained from the Health Research Ethical Committee of the institution dated November 26, 2012, with reference number ABUTH/HREC/TRG/36. Written informed consent for participation in the study and possible publication was obtained from the participants. Confidentiality was maintained with the data obtained.

Data analysis

Data entry and statistical analysis were done using the Statistical Package for the Social Sciences (SPSS) software (version 17; SPSS, Chicago, IL, USA). Descriptive statistics was used to compute mean, range, median, and standard deviation for quantitative variables as well as frequencies. The relationship between categorical variables was determined using Chi-square test. Patients were categorized into poor HRQoL score and good HRQoL score. Poor HRQoL was defined as mean HRQoL of controls – 2 standard deviation.[17] P < 0.05 was statistically significant.


  Results Top


A total of 206 comprised 103 epilepsy patients and 103 controls of comparable age and sex participated in this study.

Sociodemographic characteristics of the study participants

The mean age of the patients was 33.4 ± 15.8 years with a range of 18–75 years, while the mean age of controls was 34.5 ± 11.8 with a range of 18–73 years. The median age for the patients and controls was 29 and 31 years, respectively. There was no significant difference in age between the two groups (P = 0.571). The 21–30 years age group was the most common among the patients (36, 35.0%) and controls (42, 40.8%), whereas the least proportion of patients (8, 7.8%) and controls (5, 4.9%) were in the age group of 61 years and above. Both the patients (77, 74.8%) and controls (76, 73.8%) were observed to be predominantly young, i.e., ≤40 years. Details are shown in [Table 1].
Table 1: Sociodemographic characteristics of participants

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Both subjects and controls consisted of a total of 54 males (52.4%) and 49 females (47.6%) each. The male-to-female ratio for both the groups was 1.1:1.0, with a slight male predominance.

Thirty-nine (37.9%) patients were married and 64 (62.1%) were unmarried, while in the control group, 62 (60.2%) were married and 41 (39.8%) were unmarried. There was a statistically significant difference in the marital status of the PWE and controls (χ2 = 9.873, P = 0.002) as shown in [Table 1]. Twenty-one (20.4%) patients and 15 (14.6%) controls had no formal education. However, 82 (79.6%) patients and 88 (85.4%) controls had formal education. There was no statistically significant difference in educational status between PWE and controls (χ2 = 1.076, P = 0.300) as shown in [Table 1]. The employment status of the participants is shown in [Table 1].

Clinical characteristics of patients with epilepsy

There was a statistically significant difference in the number of patients who had seizure onset at ≤40 years (P = 0.0005), illness duration of ≤10 years (P = 0.001), were using monotherapy (P = 0.0005), and had social support (P = 0.0005), as shown in [Table 2].
Table 2: Clinical characteristics of persons with epilepsy

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Comparison of health-related quality of life scores of patients and controls

Overall score

Using the WHOQOL-BREF questionnaire, the mean HRQoL score of the patients' was 65.2 ± 16.4, while that of the controls was 69.6 ± 14.6. The mean HRQoL of patients was significantly lower than that of the controls (P = 0.042), as shown in [Table 3].
Table 3: Comparison of mean facet/domains health-related quality of life scores for patients and controls

Click here to view


Using 40.4 as the derived cutoff value for poor HRQoL, among the patients, 7 (6.8%) had poor HRQoL and 96 (93.2%) had good HRQoL as against 8 (7.8%) and 95 (92.2%), respectively, in the controls. The difference was not statistically significantly (χ2 = 0.072, P = 0.789).

Domain scores

Further analysis of the data showed the differences in mean in the domains and the general health facet HRQoL scores between the patients and controls, as shown in [Table 3]. The PWE had significantly lower mean HRQoL than the controls in the general health facet (P = 0.0005), physical health (P = 0.006), and psychological (P = 0.025) domains. However, there was no statistically significant difference between PWE and controls in the social relationship (P = 0.496) and environmental health (P = 0.606) domains.


  Discussion Top


In this study, over three-quarter of the patients were young. The finding is similar to previous studies which found the disease to be common among the young people in Nigeria.[18],[19],[20] The high frequency of the disease in this age group could be attributable to the prevalence of head trauma, a major risk factor for epilepsy in younger people.[19]

The present study showed a slight male preponderance, as 52.4% were male and 47.6% were female. Earlier studies had revealed a similar trend.[18],[20] This could be a reflection of the role of culture and tradition in hospital attendance in Northern Nigeria where tradition confines the female to the home, while a decision for health seeking must be approved by their husband or father.

Most of the patients (62.1%) were unmarried compared to the controls (39.8%). This is consistent with the finding of earlier investigators.[18],[20],[21],[22] The stigma and discrimination associated with the disease could make them lose their spouse, or for the unmarried, find it impossible to marry.[18],[22],[23] Hence, the need for public enlightenment campaigns on epilepsy to improve the perception of the people about the illness.

The proportion of patients with no formal education was very similar. Previous studies have shown that epilepsy affects the academic attainment of its sufferers[21],[22] The unpredictable nature of the seizures could affect concentration, performance, and school attendance. Furthermore, some parents withdraw their children from school either voluntarily or through compulsory expulsion by the school authorities because of the illness.[18]

More of the patients, 60 (58.2%), were found to be unemployed compared to the controls 34 (33.0%). Similarly, 60 (83.3%) of them earned a monthly income of < ₦50,000.00 compared to the controls 72 (72.0%). Previous investigators had shown that PWE were more likely to be unemployed or doing menial (unskilled) jobs with consequent poor income.[18],[21],[22]

In this study, the mean HRQoL of PWE was significantly lower than that of the controls. An earlier study in Kenya which used the WHOQOL-BREF instrument also reported significantly impaired HRQoL in patients compared to healthy controls.[21] Similarly, Ohaeri and colleagues in Sudan utilized the same questionnaire and documented impaired HRQoL in epilepsy patients compared to the healthy control group.[8] The finding in the present study is consistent with several previous reports which observed that persons with epilepsy have impaired HRQoL in comparison with healthy controls.[9],[21],[24] One of the attributable reasons for poor HRQoL in PWE includes the unpredictable nature of seizures, especially when it is uncontrolled. This is because some investigators have shown that uncontrolled seizures were associated with worsened HRQoL.[25],[26] The present study shows that 41.7% of the PWE still had uncontrolled seizures within a month prior to their visit. Therefore, good seizure control should be one of the goals in epilepsy care. To ensure adequate seizure control in patients, it is necessary to classify seizure appropriately and administer the most suitable antiepileptic drug preferably as a monotherapy.[25]

The present study also showed that PWE had significantly lower HRQoL scores in their general health facet, physical health, and psychological health domains compared to the controls. However, no significant difference was observed in their social relationship and environmental health domains in comparison with the controls. In their study, Kinyanjui et al. in Kenya had reported significantly impaired HRQoL in the four domains as well as the general health facet in PWE compared to healthy controls which was slightly different from the finding in this study.[21]

Majority, (85.4%), of the patients in this study admitted that they received adequate social support during the illness which has been shown to be associated with improved HRQoL in epilepsy.[27] The availability of adequate social support may also explain the higher though nonsignificant HRQoL score of PWE compared to that of the healthy controls in the social relationship domain as observed in this study. Social support is an important component in managing PWE.

As found in this study, the physical health and the psychological health domains were significantly impaired in epilepsy patients compared to the healthy controls. Epilepsy has been shown to cause significant impairment in physical health functioning as well as psychological disturbances such as depression and felt stigma which, in turn, adversely affects the HRQoL of the patients.[28],[29] The above findings call for the need to give targeted interventions on these domains to mitigate the impact of the illness on their overall HRQoL.

Limitations

This study was cross-sectional in design while a longitudinal study would have assessed HRQoL over time. Despite this, the findings here are relevant.


  Conclusion Top


This study had shown that epilepsy significantly impaired HRQoL of its sufferers compared to healthy controls, especially in the general health facet, physical health, and psychological health domains. Therefore, it is imperative to identify the domain (s)/facet (s) most affected in PWE to give evidence-based individualized intervention, focused treatment, and care to improve HRQoL and overall outcome of the patients.

Financial support and sponsorship

This study was self-sponsored.

Conflicts of interest

There are no conflicts of interest.



 
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    Tables

  [Table 1], [Table 2], [Table 3]



 

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