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ORIGINAL ARTICLE
Year : 2022  |  Volume : 29  |  Issue : 1  |  Page : 7-14  

The quality of life of medically versus surgically treated primary open-angle glaucoma patients at a Nigerian hospital


1 Department of Ophthalmology, Prince Abdulaziz Bin Musaad Hospital, Arar, Northern Border region, Saudi Arabia
2 Department of Ophthalmology (Guinness Eye Centre), Lagos University Teaching Hospital, College of Medicine of the University of Lagos, Lagos, Nigeria
3 Department of Ophthalmology (Guinness Eye Centre), Lagos University Teaching Hospital, Lagos, Nigeria
4 Product Development Clinical Science, Genentech Inc. South San Francisco, CA, USA

Date of Submission09-Jul-2022
Date of Acceptance25-Oct-2022
Date of Web Publication23-Nov-2022

Correspondence Address:
Dr. Femi C Oduneye
Prince Abdulaziz Bin Musaad Hospital, Arar, Northern Border
Saudi Arabia
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/meajo.meajo_146_22

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   Abstract 


PURPOSE: The purpose of this study is to compare the quality of life (QoL) of medically treated versus surgically treated primary open-angle glaucoma (POAG) patients attending Lagos University Teaching Hospital, Lagos, Nigeria.
METHODS: The study was a hospital-based, comparative cross-sectional study. Consecutive consenting POAG participants who met the inclusion criteria were recruited until the sample size was achieved. QoL of all participants was assessed using the glaucoma QoL-15 and National Eye Institute Visual Function Questionnaire-25 (NEI-VFQ-25) questionnaires. Analysis was done using the IBM statistical package for the social sciences version 25.0.
RESULTS: The study involved 81 participants who were only on medical treatment for POAG and 81 age- and sex-matched POAG participants who had trabeculectomy surgery. Surgically treated participants had a lower mean intraocular pressure 11.68 mmHg when compared to the medically treated participants 14.82 mmHg. Medically treated participants however had a better overall mean glaucoma QoL using the glaucoma QoL-15 (medical 34.36 ± 10.4, surgical 39.11 ± 13.9 P = 0.015) and NEI-VFQ-25 questionnaires (medical 68.32 ± 15.0, surgical 62.44 ± 18.8 P = 0.029). Controlling for the severity of glaucoma using the glaucoma QoL-15 questionnaire, medically treated participants had a better QoL only among participants with severe POAG (medical 49.13 ± 5.9, surgical 54.06 ± 4.6 P = 0.003). While using the NEI-VFQ-25 questionnaire, medically treated participants had a significantly better QoL only among participants with moderate (medical 74.70 ± 6.6, surgical 67.07 ± 15.6 P = 0.012) and severe POAG (medical 54.52 ± 6.3, surgical 45.51 ± 10.0 P = 0.004).
CONCLUSION: The study demonstrated that although participants that had trabeculectomy had a lower mean intraocular pressure, their overall mean QoL was reduced compared to the medically treated participants.

Keywords: Glaucoma, medical treatment, Nigeria, primary open-angle glaucoma, quality of life, surgical treatment


How to cite this article:
Oduneye FC, Musa KO, Agboola SA, Idowu OO, Onakoya AO. The quality of life of medically versus surgically treated primary open-angle glaucoma patients at a Nigerian hospital. Middle East Afr J Ophthalmol 2022;29:7-14

How to cite this URL:
Oduneye FC, Musa KO, Agboola SA, Idowu OO, Onakoya AO. The quality of life of medically versus surgically treated primary open-angle glaucoma patients at a Nigerian hospital. Middle East Afr J Ophthalmol [serial online] 2022 [cited 2022 Nov 26];29:7-14. Available from: http://www.meajo.org/text.asp?2022/29/1/7/361872




   Introduction Top


Glaucoma is the leading cause of irreversible blindness worldwide and there has been a steady increase in its worldwide prevalence.[1] In 2020, it was estimated that 80 million patients worldwide had glaucoma, out of which 11.2 million were blind.[2] Although glaucoma was not included in Vision 2020: The Right to Sight priority eye diseases, the burden of visual impairment and blindness from glaucoma rank high among eye diseases of public health importance.

Primary open-angle glaucoma (POAG) is defined as a multifactorial, chronic progressive optic neuropathy. Characterized by loss of retinal ganglion cells with characteristic optic nerve head cupping and corresponding visual field loss in a patient with open anterior chamber angles.[3] Patients with glaucoma develop characteristic progressive reduction in the peripheral visual field. Central vision is extinguished last and vision loss in glaucoma is said not to be profound until the late stages of the disease.

Intraocular pressure (IOP) remains the only modifiable risk factor in glaucoma to which all forms of therapy are currently directed to reduce the burden of visual impairment and blindness related to POAG.[3] Available therapeutic options in controlling IOP include medical treatment in the form of eye drops, intracameral medication, and systemic (oral and intravenous) hypotensive agents; laser therapy such as selective laser trabeculoplasty, and cyclophotocoagulation; and surgical intervention including trabeculectomy, tube/shunt, and minimally invasive glaucoma surgeries. However, treatment burdens such as costs of medications, frequent instillation of one or more drugs per day, and systemic and ocular side effects associated with any of these modalities may significantly reduce patient's quality of life (QoL).[4],[5],[6] For example, Loon et al. observed that only 19.7% of medically treated glaucoma patients were adherent to their medication and lack of adherence was attributed to reduced QoL, and lack of confidence in the efficacy of the medications.[5]

Similarly, successful glaucoma surgery even without complications affects the QoL of patients.[6] Immediate postoperative discomforts, gritty sensation from the bleb, and possible reduction in vision quality despite return of visual acuity to preoperative value all affect the QoL of glaucoma patients. In the Collaborative Initial Glaucoma Treatment Study (CIGTS), there was comparable satisfaction in the patient's QoL following either medical or surgical treatment of POAG. However, there were more localized eye symptoms in patients that had trabeculectomy.[7]

QoL represents an individual's perception and satisfaction with his/her status in life which is affected by physical health, mental health, psychosocial state, and relationship with the environment.[8] The QoL of glaucoma patients measures the effect of glaucoma and its management on the daily activities of the patient. Clinicians concentrate on clinical parameters such as optic nerve head changes, visual field progression, visual acuity, and target IOP in the management of glaucoma patients. However, these parameters do not measure the full extent of visual disability.[9] Patients, on the other hand, are more concerned on how the treatment modalities affect their QoL.[7],[8],[10] POAG patients on follow-up could be unsatisfied and unhappy with their visual function and their perceived QoL even though clinically the ophthalmologists are satisfied with the patient's stable visual acuity, IOP, and visual field.[6],[8] Glaucoma patients, even with similar visual deterioration, have a varying view of their QoL. Therefore, assessing QoL in medically and surgically treated POAG patients in Nigeria is important to support holistic glaucoma care delivery.

More importantly, routine assessment of patients' Qol will enable clinicians to have an idea of the individualized difficulties glaucoma patients have in performing daily activities even in patients with good central vision. Information from this study can help in the counseling of POAG patients to make informed decision on either medical or surgical management, which is specifically tailored for the patient. The current study, therefore, compared the QoL of medically treated versus surgically treated POAG patients in Lagos, Nigeria, with a view to improving the holistic management of POAG patients.


   Methods Top


This study was a hospital-based, comparative cross-sectional study, among medically treated POAG patients and age- and sex-matched surgically treated POAG patients. Ethical approval was obtained from the Health Research Ethics Committee of Lagos University Teaching Hospital with Approval Number ADM/DCST/HREC/APP/2932. The study was conducted over 26 weeks among patients attending Guinness Eye Centre, Lagos University Teaching Hospital, Lagos, Nigeria. The study adhered to the tenets of the Declaration of Helsinki and written informed consent was obtained from all study participants.

The sample size of 81 for each group was calculated.[11] Consecutive consenting participants who met the inclusion criteria were recruited until the sample size was achieved. The inclusion criteria included POAG patients 18 years and above, who had uncomplicated, simple trabeculectomy with antimetabolite surgery >3 months before the commencement of the study to prevent bias from surgical experience; and POAG patients 18 years and above who have been on medical treatment only for >3 months. Patients with chronic medical condition and those who have had any ocular surgery apart from trabeculectomy were excluded from the study. Patients with IOP >20 and <6 mmHg were also excluded from the study.

All participants underwent a standardized clinical examination protocol including POAG staging which was based on the Hodapp–Anderson–Parish classification.[12] Assessment of the QoL was done through Interviewer-administered glaucoma-specific, glaucoma quality of life-15 (GQL-15) Questionnaire and vision-specific National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) QoL instruments.

Glaucoma QoL-15 was produced by Nelson et al.[13] It consists of 15 questions grouped under four subscales which include central vision, peripheral vision, dark adaptation, and glare/outdoor mobility.[13] Central vision subscale comprises two questions; peripheral vision subscale comprises six questions; dark adaptation and glare subscales consists of six questions, and outdoor mobility subscale has only one question. GQL-15 has a good correlation with patients' stereopsis, contrast sensitivity, dark adaptation, and visual field.[13] GQL-15 is very reliable with good internal consistency.[14] The lower the GQL-15 scores the better the QoL.

The NEI-VFQ-25 is a 25-item vision-specific QoL questionnaire. NEI-VFQ-25 was developed in 2001 from a 51-item questionnaire by Mangione et al.[15] NEI-VFQ-25 is grouped into 12 domains which include general health, general vision, ocular pain, difficulty with near vision activities, distant vision limitations, limitation of social function due to vision, mental health, role limitation due to vision, dependency on others, driving difficulties, difficulty with color vision, and difficulty with peripheral vision. NEI-VFQ-25 was developed to assess the effects of chronic ocular disease on patients' subjective perception of their visual function.[15] NEI-VFQ-25 is the most widely used questionnaire for the assessment of vision-related QoL and has a good validity, reliability, and internal consistency.[9],[15] The higher the NEI-VFQ 25 scores, the better the QoL.

Data entry and analysis were done using the IBM Statistical Package for the Social Sciences (SPSS) for windows version 25.0 (IBM Corp, Armonk, NY, USA). Association between categorical variables was carried out using Chi-square. The mean comparison of GQL-15 and NEI-VFQ-25 between two groups was carried out using an independent Student t-test while analysis of variance was used to compare more than two groups. P < 0.05 was considered statistically significant at 95% confidence interval.


   Results Top


The sociodemographic characteristics of the participants are summarized in [Table 1]. Their ages ranged from 18 to 82 years. There were more males than females in both groups with a male-to-female ratio of 1.3:1. There was no statistically significant difference in age, sex, marital status, ethnic group, and level of education between the two groups. There was a progressive reduction in the QOL in both POAG groups with increasing age using both Qol-15 and NEIVFQ-25 Questionnaires as shown in [Table 6] and [Table 7]. However increased level of education was found to be associated with an increased Qol in both POAG groups as shown in [Table 6] and [Table 7].
Table 1: Sociodemographic characteristics of participants (n=81)

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Table 2: Mean comparison of quality of life of medically and surgically treated primary open-angle glaucoma patients using glaucoma quality of life-15 questionnaire (n=81)

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Table 3: Mean comparison of quality of life of medically and surgically treated primary open-angle glaucoma patients according to glaucoma severity using glaucoma quality of life-15 questionnaire

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Table 4: Mean comparison of the quality of life of medically and surgically treated primary open-angle glaucoma patients using National Eye Institute visual function questionnaire-25 questionnaire (n=81)

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Table 5: Mean comparison of quality of life of medically and surgically treated glaucoma patients according to their severity using the National Eye Institute Visual Function Questionnaire-25

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Table 6: Mean comparison of overall quality of life scores using glaucoma quality of life-15 questionnaire in primary open-angle glaucoma patients according to their sociodemographic characteristics

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Table 7: Mean comparison of overall quality of life scores using National Eye Institute Visual Function Questionnaire-25 in primary open-angle glaucoma patients according to their sociodemographic characteristics

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As shown in [Figure 1], the mean intraocular pressure was lower in POAG participants that had surgery (11.68 mmHg) compared to POAG participants on ocular medications (14.82 mmHg). The medically treated POAG participants had a better overall mean glaucoma-specific QoL compared to the surgically treated POAG participants as shown in [Table 2]. Adjusting for severity as shown in [Table 3], there was no statistically significant difference in the QoL between medically and surgically treated POAG participants that had mild and moderate glaucoma. Severe POAG participants who were medically treated however had a better glaucoma-specific QoL compared to the surgically treated participants (P = 0.003). Glare and dark adaptation domains were most affected in all groups.
Figure 1: IOP among POAG patients. IOP: Intraocular pressure, POAG: Primary open-angle glaucoma

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Using the NEI-VFQ-25 questionnaire, POAG participants who had trabeculectomy seemed to have worse overall mean vision-related QoL compared to those that were only on medications as shown in [Table 4]. The driving domain was most affected in both groups. Adjusting for severity, there was no statistically significant difference in the QoL between medically and surgically treated POAG participants that had mild glaucoma as depicted in [Table 5]. However, POAG participants who had trabeculectomy had a worse vision-related QoL among the moderate (P = 0.012) and severe (P = 0.004) POAG groups.

Using GQL-15 questionnaire to compare the overall QOL scores of both POAG study groups according to their socio-demographic characteristics, there was a progressive reduction in quality of life with increasing age in both groups (P<0.001) as shown in [Table 6]. There was also a progressive increase in the quality of life with increasing level of education in both medically and surgically treated POAG patients (P=0.283), (P=0.001).

While using NEIVFQ-25 Questionnaire, there was also a progressive reduction in quality of life with increasing age in both groups (P<0.001) as shown in [Table 7]. Participants that were single in both groups had better quality of life compared to those that were married (P<0.001). And there was also a progressive increase in the quality of life with increasing level of education in both medically and surgically treated POAG patients (P=0.022), (P<0.001).


   Discussion Top


The mean age of POAG participants on medications as the only form of treatment was 49.24 ± 17.3 years, whereas the mean age of surgically treated POAG participants was 48.38 ± 16.7 years. The mean age of POAG among African-Americans in the United States of America is 70.2 years,[16] whereas the mean age of POAG in the United Kingdom, Brazil, and India are 71.8 years,[17] 57.7 years,[18] and 59 years, respectively.[19] The reduction in the mean age of POAG patients in this study could be as a result of the inclusion of a juvenile open-angle glaucoma patients who are 18 years and above into this study population. Other studies earlier mentioned recruited POAG participants that were 40 years and older.

There was a slight male preponderance (55.6%) in both medically and surgically treated POAG participants with a ratio of 1.3:1. The slight male preponderance in this study could be as a result of the fact that in the developing world, males easily access health facilities compared to females because they are more financially empowered and women are mostly at home.[20]

Using both GQL-15 and NEI-VFQ-25 questionnaires in this study, QoL was found to progressively reduce with increasing age in both medically and surgically treated POAG participants (P < 0.001). Similarly Onakoya et al.,[21] Labiris et al.,[22] and Magacho et al.[23] revealed that increasing age negatively affected the QOL of POAG patients. This could be due to a combination of factors which include different perceptions of life by young people, relative worsening of glaucoma with age- and relative-associated increase in comorbidities with age which affects subjective perception of QoL.[24]

This study found a progressive improvement in the QoL with increasing the level of education in both medically and surgically treated POAG patients. Similar findings were reported by Guedes et al.[4] and Onakoya et al.[21] This could be because educated people are more enlightened and have a relatively better understanding of their ocular disease and more likely to be adherent to the available treatment options.

Glaucoma-specific and vision-related QoL in this study were found to worsen with progressive increase in POAG severity in both medically and surgically treated POAG patients. This was similar to the observation reported by Guedes et al.[4] and Onakoya et al.[21] As the glaucoma progresses, patients find it increasingly difficult to carry out their daily routine, which in turn worsens the perception of their QoL.

In this study, despite the fact that surgically treated POAG participants had a lower mean intraocular pressure (11.68 mmHg) when compared with the medically treated POAG participants (14.82 mmHg), medically treated POAG participants had a better overall mean QoL compared to the surgically treated POAG participants using GQL-15 (P = 0.015) and NEI-VFQ-25 questionnaires (P = 0.029).

However, controlling for the severity of POAG, the medical group only had better QoL scores compared to the surgical group among participants with severe POAG (P = 0.003) using the GQL-15. Using NEI-VFQ-25 questionnaire, the medical group had better vision-related QoL scores among participants with moderate (P = 0.012) and severe POAG (P = 0.004). It was not readily obvious why medically treated severe glaucoma patients had better QoL. It could be as a result of worsening of the visual quality following trabeculectomy despite better IOP control and stability of the visual field.

These findings were slightly different from that seen by Guedes et al.,[4] who also compared the QoL between medically and surgically treated POAG patients in Brazil. Guedes et al. reported a better overall mean QoL in patients on medical treatment for glaucoma compared with surgically treated glaucoma patients. However, controlling for severity, patients with moderate and advanced POAG were reported to have similar QoL scores, whereas glaucoma surgery worsened the QoL of patients with early POAG.[4] The CIGTS reported no difference in the QoL of medically and surgically treated POAG patients among all severity groups.[7] QoL is influenced by regional cultural practices, religious beliefs, and personal life experiences.[8] The difference in the QoL findings in this study could be attributed to the possibility that Nigerians have a different perspective of their disease which is affected by their sociocultural upbringing and environment.


   Conclusion Top


This study is limited by the subjectivity of the response to the QoL questionnaires, which could introduce bias to the study. In conclusion, the overall mean QoL of medically treated POAG patients was better than those that had trabeculectomy, even though participants that had trabeculectomy had a better controlled intraocular pressure. Clinicians should not solely strive to achieve the target intraocular pressure set for the patient but consider the effect of the treatment regimen on patient's QoL. Using the GQL-15 questionnaire, the glare and dark adaptation domains were most affected in both medically and surgically treated POAG patients. While driving, the domain was found to be most affected using NEI-VFQ-25. The GQL-15 and NEI-VFQ-25 questionnaires should be included in the routine clinical assessment and monitoring of POAG patients. This would give an idea of the patient's reported outcome and holistic management of their ocular condition and treatment.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.


   Questionnaire Top


Glaucoma GQL-15 and NEI-VFQ-25 questionnaires

Glaucoma Quality of life Questionnaire GQL-15

Interviewer instruction: Please, circle the correct answer on a scale ranging from 1 to 5 where (1) stands for no difficulty, (2) for a little bit of difficulty, (3) for some difficulty, (4) for quite a lot of difficulty, and (5) for severe difficulty. If you do not perform any of the activities other than visual reasons, please circle (0)

Does your vision give you any difficulty, even with glasses, with the following activities?





 
   References Top

1.
Flaxman SR, Bourne RR, Resnikoff S, Ackland P, Braithwaite T, Cicinelli MV, et al. Global causes of blindness and distance vision impairment 1990-2020: A systematic review and meta-analysis. Lancet Glob Health 2017;5:e1221-34.  Back to cited text no. 1
    
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Quigley HA, Broman AT. The number of people with glaucoma worldwide in 2010 and 2020. Br J Ophthalmol 2006;90:262-7.  Back to cited text no. 2
    
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Kwon YH, Fingert JH, Kuehn MH, Alward WL. Primary open-angle glaucoma. N Engl J Med 2009;360:1113-24.  Back to cited text no. 3
    
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Guedes RA, Guedes VM, Freitas SM, Chaoubah A. Quality of life of medically versus surgically treated glaucoma patients. J Glaucoma 2013;22:369-73.  Back to cited text no. 4
    
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Loon SC, Jin J, Jin Goh M. The relationship between quality of life and adherence to medication in glaucoma patients in Singapore. J Glaucoma 2015;24:e36-42.  Back to cited text no. 5
    
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Klink T, Sauer J, Körber NJ, Grehn F, Much MM, Thederan L, et al. Quality of life following glaucoma surgery: Canaloplasty versus trabeculectomy. Clin Ophthalmol 2015;9:7-16.  Back to cited text no. 6
    
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Janz NK, Wren PA, Lichter PR, Musch DC, Gillespie BW, Guire KE, et al. The Collaborative initial glaucoma treatment study: Interim quality of life findings after initial medical or surgical treatment of glaucoma. Ophthalmology 2001;108:1954-65.  Back to cited text no. 7
    
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Spratt A, Kotecha A, Viswanathan A. Quality of life in glaucoma. J Curr glaucoma Pract 2008;2:39-45.  Back to cited text no. 8
    
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Suzukamo Y, Oshika T, Yuzawa M, Tokuda Y, Tomidokoro A, Oki K, et al. Psychometric properties of the 25-item national eye institute visual function questionnaire (NEI VFQ-25), Japanese version. Health Qual Life Outcomes 2005;3:65.  Back to cited text no. 9
    
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Odberg T. Visual field prognosis in advanced glaucoma. Acta Ophthalmol 1987;65:27-9.  Back to cited text no. 10
    
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Araoye MO. Research Methodology with Statistics for Health and Social Sciences. 1st ed. Ilorin: Nathadex Publishers, Sawmill; 2004. p. 115-21.  Back to cited text no. 11
    
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Mbadugha CA, Onakoya AO, Aribaba OT, Akinsola FB. A comparison of the NEIVFQ25 and GQL-15 questionnaires in Nigerian glaucoma patients. Clin Ophthalmol 2012;6:1411-9.  Back to cited text no. 12
    
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Severn P, Fraser S, Finch T, May C. Which quality of life score is best for glaucoma patients and why? BMC Ophthalmol 2008;8:2.  Back to cited text no. 14
    
15.
Mangione CM, Lee PP, Gutierrez PR, Spritzer K, Berry S, Hays RD, et al. Development of the 25-item national eye institute visual function questionnaire. Arch Ophthalmol 2001;119:1050-8.  Back to cited text no. 15
    
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Khachatryan N, Pistilli M, Maguire MG, Salowe RJ, Fertig RM, Moore T, et al. Primary open-angle African American glaucoma genetics (POAAGG) study: Gender and risk of POAG in African Americans. PLoS One 2019;14:e0218804.  Back to cited text no. 16
    
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Paul C, Sengupta S, Choudhury S, Banerjee S, Sleath BL. Prevalence of glaucoma in Eastern India: The hooghly river glaucoma study. Indian J Ophthalmol 2016;64:578-83.  Back to cited text no. 19
[PUBMED]  [Full text]  
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Onakoya AO, Mbadugha CA, Aribaba OT, Ibidapo OO. Quality of life of primary open angle glaucoma patients in Lagos, Nigeria: Clinical and sociodemographic correlates. J Glaucoma 2012;21:287-95.  Back to cited text no. 21
    
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Labiris G, Katsanos A, Fanariotis M, Zacharaki F, Chatzoulis D, Kozobolis VP. Vision-specific quality of life in greek glaucoma patients. J Glaucoma 2010;19:39-43.  Back to cited text no. 22
    
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Magacho L, Lima FE, Nery AC, Sagawa A, Magacho B, Avila MP. Quality of life in glaucoma patients: Regression analysis and correlation with possible modifiers. Ophthalmic Epidemiol 2004;11:263-70.  Back to cited text no. 23
    
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Gupta V, Dutta P, OV M, Kapoor KS, Sihota R, Kumar G. Effect of glaucoma on the quality of life of young patients. Invest Ophthalmol Vis Sci 2011;52:8433-7.  Back to cited text no. 24
    


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  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7]



 

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