Nigerian Journal of Clinical Practice

ORIGINAL ARTICLE
Year
: 2021  |  Volume : 24  |  Issue : 8  |  Page : 1117--1125

Visual Morbidities among Patients at a Geriatric Center in Southwest Nigeria and the Merits of Designated Geriatric Health Care Centers Incorporating Eye Care Services


OA Ogun1, LA Adebusoye2, OO Olowookere2, OI Majekodunmi3,  
1 Department of Ophthalmology, University College Hospital and College of Medicine, University of Ibadan, Ibadan, Nigeria
2 Chief Tony Anenih Geriatric Centre, University College Hospital, Ibadan, Nigeria
3 Department of Ophthalmology, University College Hospital, Ibadan, Nigeria

Correspondence Address:
Dr. L A Adebusoye
Chief Tony Anenih Geriatric Centre, University College Hospital, Ibadan
Nigeria

Abstract

Background: Visual morbidities increase the burden of care and negatively impact the quality of life of older people. Few empirical reports exist on the visual status of older Nigerians. Aim: This study describes the visual morbidities and determinants of visual impairment among persons aged 60 years and above who presented at a geriatric center in southwestern Nigeria and discusses the merits of focused geriatric care at a single location. Materials and Methods: Data were obtained from electronic health records and case files of 628 older patients (≥60 years) who attended the facility between January 1, 2014 and December 31, 2018. Data extracted included, age, sex, married status, occupational status, visual acuity, eye diagnoses, eye medications, previous surgeries, and anthropometric measurements. Results: Mean age of patients was 70.1 ± 7.4 years and 378 (60.2%) were females. Two out of every three patients had more than one visual diagnosis. Significantly, glaucoma (P < 0.001) and cataract (P = 0.01) were common among men, whereas dry eye syndrome (P < 0.001) and allergic conjunctivitis (P = 0.01) were common in women. Antiglaucoma medications (55.8%) were the commonest medications used and 21.0% had previous eye surgery. Assessment of presenting visual acuity demonstrated that 28.7% of patients had moderate-severe visual impairment (MSVI) in both eyes at presentation while 10.3% were bilaterally blind. Increasing age (P < 0.001) and male sex (P = 0.01) were the factors significantly associated with blindness. Conclusion: MSVI and blindness were common in our setting with glaucoma and cataract being the most prevalent associated diagnosis. Information obtained should stimulate advocacy for the prompt management of preventable causes of poor vision in older Nigerians.



How to cite this article:
Ogun O A, Adebusoye L A, Olowookere O O, Majekodunmi O I. Visual Morbidities among Patients at a Geriatric Center in Southwest Nigeria and the Merits of Designated Geriatric Health Care Centers Incorporating Eye Care Services.Niger J Clin Pract 2021;24:1117-1125


How to cite this URL:
Ogun O A, Adebusoye L A, Olowookere O O, Majekodunmi O I. Visual Morbidities among Patients at a Geriatric Center in Southwest Nigeria and the Merits of Designated Geriatric Health Care Centers Incorporating Eye Care Services. Niger J Clin Pract [serial online] 2021 [cited 2022 May 16 ];24:1117-1125
Available from: https://www.njcponline.com/text.asp?2021/24/8/1117/323863


Full Text



 Introduction



The population of the elderly has been on an upward trend worldwide, owing to the reduction in childhood mortality, enhanced living conditions, and increasing access to quality healthcare, thus having a consequential effect on the health and socioeconomic systems of nations. Moreover, it is estimated that by 2050, 80% of the estimated 1.5 billion people aged 65 years and older will reside in the less developed countries of the world.[1],[2] This demographic transformation predisposes to an increase in the prevalence of ensuing health challenges and disabilities associated with aging. For instance, it was estimated that the elderly constitute 65% of all visually impaired and 85% of the blind, among the 285 million people with visual disability worldwide,[3] and this was expected to double by the year 2020 with more than two-thirds of them having severe visual impairment.[4],[5] A recent study among the elderly in India showed that 30.1% had visual impairment, of which 88.1% was treatable.[6] This increasing prevalence of age-related eye diseases compounded by the existing gaps in eye care services results in needless visual impairment and poor quality of life in resource-poor countries like Nigeria.

The etiology of visual impairment varies with age, sex, and geographical location in different populations.[7] Factors responsible include increasing life expectancy.[1],[2] and the unequal distribution of ophthalmic healthcare services and resources.[8],[9] Cataract, uncorrected refractive error, glaucoma, age-related macular degeneration (ARMD), etc., continue to be the collective causes of a majority of visual impairment and blindness among the elderly worldwide despite numerous efforts aimed at reducing their burden.[3],[4],[9],[10],[11],[12] This is further worsened by disabling systemic conditions, dwindling financial resources, and low utilization of the limited eye care services; especially in the low-income countries of the world.[13] Visual impairment and blindness affect the ability of the elderly to perform daily tasks like self-care activities, therefore making them more dependent on others. As a result, vision loss has been ranked third (behind arthritis and heart disease) among the most common chronic conditions that impair the ability to perform activities of daily living (ADL) among older adults aged 70 years or more,[14],[15],[16] resulting in vision-related dependency.

The public health significance of visual impairment is expected to rise due to the increasing proportions of the elderly in different populations.[4] An important consequence of visual impairment is its effect on diverse domains and impact on the quality of life in the elderly.[17],[18],[19]

There is a need for regular evaluation of the elderly to facilitate early detection of potentially blinding ocular disorders such as glaucoma, cataract, ARMD, and uncorrected refractive errors including presbyopia, thereby preventing unnecessary disability and dependency.[20] This can further be strengthened by encouraging routine vision screening during general health assessment visits. This study was therefore designed to identify the common causes of ocular morbidity in a typical indigenous Nigerian older population attending a geriatric clinic for eye care.

 Materials and Methods



Setting and Study Design

This was a retrospective descriptive hospital-based study of all patients aged ≥60 years who attended the Eye Clinic of the Chief Tony Anenih Geriatric Centre (CTAGC), University College Hospital (UCH), Ibadan in Southwestern Nigeria between January 1, 2014 and December 31, 2018. The CTAGC was established on November 17, 2012 and the Eye Clinic became fully operational on January 1, 2014. The CTAGC is the pioneer geriatric center in Nigeria, which has both outpatient and inpatient facilities, with specialty clinics. The weekly Eye Clinic is one of the CTAGC specialty clinics. It is serviced by a team from the Ophthalmology Department, UCH, Ibadan, headed by a consultant ophthalmologist. This geriatric eye clinic runs every Wednesday. All clinical data were captured and stored using electronic health records.

Data Extraction

The electronic health records and case files of all patients who attended the CTAGC Eye Clinic between January 1, 2014 and December 31, 2018 were obtained and included in the study.

We obtained information regarding sex, age, marital status, occupation, visual acuity, eye diagnoses, eye medications, previous surgeries, and anthropometric measurements.

The height was recorded in meters and weight in kilograms. These were used to derive the body mass index (BMI), which was calculated by dividing the weight (kg) by height squared (m2). The BMI was graded using the World Health Organization anthropometric classification as underweight (BMI < 18.4 kg/m2), normal (BMI 18.5–24.9 kg/m2), overweight (BMI 25.0–29.9 kg/m2), and obesity (BMI ≥ 30.0 kg/m2). Presenting visual acuity was measured using an acuity Snellen chart placed at 6 m and visual status was categorized according to the International Council of Ophthalmology visual standards.[21] Each patient had a comprehensive eye examination comprising visual acuity, refraction, anterior segment pen-torch, and slit-lamp examination with posterior segment examination carried out using ophthalmoscopy or slit-lamp biomicroscopy along with high power (+78D or +90D) fundus lenses. Ancillary investigations, such as visual field testing, ocular biometry, and pachymetry, were ordered as required. For descriptive analysis, monocular visual acuity was defined as visual acuity in either the left or the right eye, respectively, when considered alone. Binocular visual acuity was defined as visual acuity in the better eye, considering the monocular acuity of both the left and right eyes of an individual together.

Inclusion and Exclusion Criteria

No records were excluded as all health records of patients who presented at the facility within the study period were included in the study.

Ethical Considerations

The approval of the Director of the CTAGC, UCH, Ibadan was obtained. The confidentiality of data was maintained with the exclusion of names and hospital numbers from the analysis, leaving only the serial numbers allotted to the patients.

Data Analysis

The Statistical Package for the Social Sciences version 25 (IBM, Armonk, NY, USA) was used for data analysis. Appropriate charts were used to illustrate categorical variables. Continuous variables were presented as means ± standard deviations (SDs) while categorical variables were presented as frequency and percentages. Inferential statistics to test for associations between categorical and continuous variables was done using the Chi-square and Student's t-test at a 5% level of significance.

 Results



During the period under consideration, 628 patient case files were analyzed. There were 378 (60.2%) females and 250 (39.8%) males. Their mean age was 70.1 ± 7.4 and males (71.5 ± 7.9 years) had a significantly higher mean age than females (69.3 ± 6.9 years), P < 0.001. [Table 1] highlights the demographics of our participants. The majority of our patients were aged less than 70 years (52.2%), currently married (87.9%) but not working (52.1%), and were mostly traders (71.8%). The mean eye clinic attendance per patient increased significantly from 6.0 ± 3.6 times in 2014 to 11.8 ± 8.3 times in 2018 (F = 14.02, P < 0.001).{Table 1}

[Table 2] describes the exanimation findings of both eyes. For the monocular vision, the highest proportion of patients had moderate to severe visual impairment (38.2%) and normal vision (50.0%) on the right and left eyes, respectively. In the majority of patients (>90%) eyelids, conjunctivae, corneas, anterior chambers, and pupils were normal in both eyes. However, lens opacities were the commonest abnormalities in both eyes of 85% of the patients. Ptosis was observed in only 17 (1.4%) of 1256 eyes of the 628 patients. Likewise, pterygium was documented in 51 (4.1%) eyes, with corneal scars and opacities in 35 eyes (2.8%). The disc appeared pale in 449 eyes (35.7%). However, abnormal pupil reactions were only recorded in 92 eyes (7.3%).{Table 2}

The visual diagnoses by sex distribution are shown in [Table 3]. Overall, 953 diagnoses were made with an average of 1.5 diagnoses per patient. A significantly higher proportion of males presented with glaucoma (P < 0.001) and cataract (P = 0.01) compared with the females. While a higher proportion of female patients were diagnosed with dry eye syndrome (P < 0.001) and allergic conjunctivitis (P = 0.01) than male patients.{Table 3}

The majority of the patients had more than one diagnosis (n = 532; (84.7%) and more than half of them (n = 319) (50.8%) were also on eye medications. Of these, 181 (56.7%) patients were using one eye medication, 28.2% were on two medications and 3.8% were on more than four eye medications. The commonest eye medications used were antiglaucoma medications 178 (55.8%) followed by tear supplements 52 (16.3%). Few patients, 114 (21.0%), had eye surgeries before presentation to the clinic; of these, cataract surgery, 68 (59.6%), was the commonest [Table 4].{Table 4}

Binocular visual acuity is described by the patients' sociodemographic characteristics and is shown in [Table 5]. The majority of patients, 383 (61.0%), had normal vision, 180 (28.7%) had MSVI, and 65 (10.3%) were categorized as blind. Increasing age (P < 0.001) and male sex (P = 0.01) were the factors that were most significantly associated with blindness.{Table 5}

Analysis of BMI, showed that 22 (3.5%) of patients were underweight, 173 (27.5%) had normal BMI, 262 (41.8%) were overweight, and 171 (27.2%) were obese. The association between binocular visual acuity and BMI is described in [Figure 1]. The majority of the overweight (63%) and obese patients (69.6%) had normal vision. On the other hand, the highest proportion of patients with blindness (22.7%) was recorded among those categorized as underweight (P < 0.001). Conversely, the lowest prevalence of blindness was observed among the overweight (11.3%) and the obese (3.5%).{Figure 1}

 Discussion



In this study, there were more female participants than males. Although a study by Ibrahim et al.[22] in Saudi Arabia showed a higher male participation rate compared to females, the findings in our study are similar to the findings of the Proyector VER study,[23] Adepegba et al.,[24] Pakistan National Blindness and Visual Impairment Survey,[25] Adio[20] and Dreer et al.,[26] where females were more represented. This difference in representation or participation may be rooted in the cultural norms of the society. For instance, females in our society may have more freedom to attend clinics and participate in a cross-sectional study without the consent of their spouses, who may not be present at the time. While on the other hand, in a society like Saudi Arabia, female mobility and visibility in society are somewhat less. Furthermore, females presenting to the Geriatric Clinic were found to have a lower mean age than men. This may suggest that the health-seeking behavior of older females is improving or that they are enjoying better social support. Social support has been found to positively influence healthy behaviors and the quality of life of the older population.[27]

The mean age of patients over the 5 years was 70.1 ± 7.4 years. This mean age differs from Adio[20] (85 ± 12.1 years) and Dreer et al.[26] (82 ± 7.7 years). Also, the majority of the patients were in their seventh decade of life and only 13% were above 80 years of age. This reflects the relatively younger demographics of our elderly population in Nigeria.

About 84% of participants had varying degrees of lens opacities diagnosed on routine eye examination. This finding may be related to an unmet need for cataract surgical services, as a result of reduced utilization of existing eye care services as previously reported by Rabiu[28] and Vela et al.[13] The three commonest ocular diseases found among the participants were glaucoma, cataract, and uncorrected refractive error with a prevalence of 57.3%, 38.7%, and 18.6%, respectively. The hospital-based nature of the study and life-long follow-up of the disease may have accounted for glaucoma being the commonest ocular disease found in this study. The prevalence of glaucoma was found to be significantly associated with the male sex (P < 0.001). The low uptake of refraction services (49.5%) among the elderly in our study could have accounted for the level of visual impairment/blindness observed in the study. Other emerging causes of ocular morbidities among older persons like ptosis, pterygium, and cornea opacities reported in other studies[29],[30],[31] were found to be low in our study.

Treatable and preventable causes of visual impairment accounted for the majority of ocular morbidities among older patients that were studied. This suggests that urgent measures need to be taken to protect the eye health of the elderly in Nigeria, to reduce the burden of unnecessary visual impairment due to the rapid changes in the demography of low-middle income countries. This has been reported in earlier studies.[32],[33],[34],[35] Similarly, the absence of free healthcare services and dwindling financial resources of older persons may have contributed to the high prevalence of ocular diseases among them. Furthermore, the chronicity of glaucoma in the absence of any known cure and the hospital-based nature of the study may have contributed to glaucoma being the commonest ocular disease in this study. The increased burden of ocular diseases among them may also be related to neglect and abandonment as well as the erroneous belief that blindness is expected in old age, hence no need for treatment.

Three hundred and eighty-three (61%) patients had good visual acuity at presentation, whereas the remainder had varying degrees of visual impairment and blindness. Findings like this are not unexpected due to the high prevalence of age-related eye diseases among older individuals. However, a major concern is the poor quality of life they could be experiencing due to associated systemic comorbidities and lack of independence to perform their basic ADL. Furthermore, our study also revealed that 532 patients have more than one eye diagnosis, whereas 96 of them had at least 3 eye diagnoses. Additionally, of those on ocular medications, 55.8% were on antiglaucoma medications. This has the potential to further worsen their health-related quality of life, due to the additional expenses incurred from purchasing medications despite dwindling incomes, as well as numerous ocular and systemic side effects of these medications.[36]

Our data demonstrated an interesting association between the prevalence of blindness and BMI. The highest prevalence of blindness (22.7%) in our study was observed among those with the lowest BMI [Figure 1]. This, however, does not mean that lower BMI predisposes to blindness, rather, it may reflect an association between body habitus (BMI) and socioeconomic status or general health status. Therefore, those with the lowest BMI may have low body weight as a result of undernutrition as a consequence of lower socioeconomic status or poor health and therefore the higher prevalence of blindness may be more directly related to these conditions of lower socioeconomic status and poorer health than BMI itself. Likewise, the lowest prevalence of blindness was found among the overweight (11.8%) and the obese (3.5%). In the same vein, it is possible to relate BMI to socioeconomic status, nutritional status, and state of general health. Therefore, blindness may be more directly related to these factors rather than BMI. It is well-known that there are huge disparities in lifestyles and access to healthcare between the major socioeconomic groups in a low-middle income country like Nigeria and these may reflect in eating habits and resulting BMI. In developing nations like Nigeria, the more affluent in society tend to readily adopt the lifestyle and eating habits of Western cultures. This predisposes to a greater tendency toward obesity and overweight. Therefore, higher BMI may be a negative predictor of blindness among the elderly in Ibadan, as a reflection of the individual's higher socioeconomic status and greater access to basic medical care. During the period under review, the mean clinic attendance of our patients was 10.0 ± 7.2 visits per patient. This translates to almost monthly visits. This high rate of adherence to follow-up by our geriatric patients may be related to two main factors. First, the highly subsidized cost of treatment at 50% of what obtains within the hospital and the provision of the voluntary insurance contribution of N18,000 ($41) per year, which covered the cost of consultation, medication, and basic laboratory investigations at the CTAGC. Second is the convenience of accessing medical consultants and the ambiance of the environment. The fact that healthcare at our geriatric center is highly subsidized may encourage patients to take better care of themselves and keep to clinic appointments because it is more affordable for them. At the geriatric center, patients have easy access to various medical specialists and consultants all within the same space and appointments are not prolonged. Special efforts were made by the CTAGC to liaise directly with consultants in the different medical and surgical specialties and commit them to specific days for consultation in dedicated consulting rooms. This flexibility enables the consultants to schedule appointments within a short time, as there is little pressure on space and supporting staff. The deployment of the electronic health management system to schedule older patients' clinic appointments and the reminder text messages, which are sent to older patients and their next of kin two days to their clinic appointment, have ensured the keeping of follow-up appointments. This also enables older patients to experience less stress as they are not queueing for long periods in a crowded space as is the case in the general eye clinic.

 Conclusion



This study has shown that MSVI and blindness are important causes of poor vision among the elderly presenting at the Geriatric Centre in Ibadan. The blindness in most patients was due to glaucoma and/or cataract. Many of these elderly patients also have at least one comorbidity. Moreover, apparently these patients require greater medical care, despite their lower earning capacity. Our observations, therefore, suggest that the establishment of designated geriatric centers where the medical and eye healthcare needs of the elderly can be met altogether in one location, along with their mental health and social needs, at a subsidized rate, or no cost at all, will go a long way in easing the burden of avoidable blindness among this vulnerable population.

Financial support and sponsorship

Self-funded.

Conflicts of interest

There are no conflicts of interest.

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