Original Research Article DOI: 10.18231/2348-7682.2018.0008 Panacea Journal of Medical Sciences, January-April 2018;8(1):34-39 34 Pattern of ocular morbidity amongst patients of elderly age group in Central India Priti Singh1,*, Rahul Agarwal2 1Assistant Professor, 2Professor and Head, Dept. of Opthalmology, 1Gandhi Medical College, Bhopal, 2LN Medical College, Bhopal, Madhya Pradesh, India *Corresponding Author: Email: singh_priti2178@yahoo.com Abstract Elderly population in India is rapidly on an increase due to increased life expectancy. Visual status is one of the most important health quality indicators for the elderly who are highly prone to develop various eye diseases which form a major health problem to them. So we have tried to study the pattern of ocular morbidity in this age group, to understand the risk factors responsible for blindness in the elderly so that we can focus on the preventive measures that we can adopt to avoid this. In our hospital bassed cross sectional study 500 patients above 50 years of age were taken. Detailed history based on pre-prepaired questionare was taken followed by complete ocular examination and relevant investigations to diagnose the ocular disease in these elderly people. We found that refractive errors followed by cataract were found to be the most common ocular problems in our sample population. Various risk factors like age, gender, residence, educational status, socio-economic status, hypertension, diabetes, cooking fuel used, smoking, alcoholism, and tobacco consumption were tabulated and there significance in causing ocular morbidity and blindness was studied. Finally we concluded that there is a high incidence of ocular morbidity in old age individuals most of the causes being either treatable or preventable. Therefore the focus should be on providing affordable quality eye care services at both the urban and rural areas so that we can prevent ocular morbity and blindness in these elderly individuals specially those with low educational and socioeconomic status. Keywords: Cataract, Glaucoma, Dry eye, Retinopathy, Refractive errors. Introduction By 2025, the population of elderly is expected to be about 840 million in low income countries.1 In India, 10.4% of the total population will be 60 years or older by 2020.2 With rapid increase in elderly population, emphasis should be laid on their better quality of life comprising physical, social and economic well being. The visual status is one of the major factors determining the quality of life.1 In 2010 anestimated 285 million people worldwide were visually disabled, about nearly 90% of them living in developing countries.1 According to a fact about 80% of the blindness is avoidable and about 65% of all people who are visually impaired are aged >50 years.1 These facts and figures signify that in a developing country, like India, little concern is given to the geriatric health problems and limited information is available about the pattern of ocular morbidity in elderly population.3 This provides a rationale to conduct our study as it will provide knowledge about prevalence of different ocular morbidities and its associated risk factors in geriatric population so that a large number of elderly population can be prevented and treated for the prevailing ocular morbidities which is also included under ‘VISION 2020: the right to sight’1 programme. The formulation of any effective intervention health programme begins with the knowledge of the magnitude of the problem in a given community. Although costly and time consuming the actual assessment of a health problem is far less expensive than the intervention itself and may suggest where and how prevention activities can best be implemented. The study was designed to diagnose elderly patients with ocular diseases by thorough history taking, examination and relevant investigations which was thenanalysed to know about the prevalence of ocular diseases. The study was significant as large and random population of both rural and urban area could be screened for the different ocular morbidites in a cost effective way. The present studyassisted to know the prevalenceof different ocular morbidities and identify their associated risk factors that may help to formulate measures to eliminate avoidable blindness and compare our results with some previous studies;enabling us to tackle it more effectively. Aims and Objectives 1. To determine the prevalence of the different types of ocular morbidities in elderly. 2. To study about the risk factors associated with ocular morbidity and prevention of blindness in elderly. Materials and Methods A hospital based cross-sectional study was carried out at ophthalmology OPD of a hospital. The sample population included patients of >50 years of age who visited the eye O.P.D in between working hours. The sample size of the population was 500. Exclusion Criteria: The patients < 50 years of age, the patients who did not give consent, and patients of dementia and mental derangements in whom the history was unreliable were excluded from the study. Priti Singh et al. Pattern of ocular morbidity amongst patients of elderly age group in Central India Panacea Journal of Medical Sciences, January-April 2018;8(1):34-39 35 Inclusion Criteria: Patients >50 years of age who visited the opd and gave consent were included in the study. An informed consent was obtained from the patient on a consent form before proceeding further. Ethical approval regarding the study was obtained from the relevant authority. A thorough history taking procedure to know the chief complaints was carriedout with special emphasis on the associated factors. A predesigned questionnaire was asked to the patient (to know about the associated factors of ocular morbidities); as given in the case record form attached.The questions were asked in a manner that the patient understood. The socio-economic status of the patient was ascertained by Kuppuswamy scale1 for urban population and Prasad’s scale4 for rural population. The patients for diabetes wereinvestigated by blood sugar estimation and for hypertension, blood pressure was recorded and diagnosed by comparing with standard results.5 After history taking, external ocular examination was done with the help of torch light and loupe.6 The visual acuity with and without pin hole was taken with the help of snellen’s chart for literate andlandolt’sC-chart for illiterate patients.6 Retinoscopy6 and/or autorefractometry6 were done to find out the refractive error. A visual acuity of <6/9 was considered as a visual impairment. A detailed examination of conjunctiva, sclera, cornea, iris, pupil, anterior chamber, lens, posterior chamber and posterior segment was carried out to find out any abnormality.6 Instruments used-Measurement of intra ocular pressure by tonometry, examination of lacrimal apparatus by syringing, Schirmer’sstrip and fundus examination by ophthalmoscope and slit lamp was done as required.6 Based on the clinical features, examinations and investigations diagnosis was confirmed for the type of ocular morbidity present.6 The data was then organised, examined and analysed to calculate the prevalence of different ocular diseases by the standard formula and methods.1 The correlation of the different factors associated with the prevalent ocular morbidities was determined and test of significance such as chi square test, chi square test with yates’ correction and fisher exact test were applied to find out any statistical significance was present or not. Results The prevalence of different ocular morbidities in the 500 patients that we examined is shown in Fig. 1. Fig. 1: Prevalence of different ocular morbidities in >50 year patients Apart from the above; less than 5 cases of the following diseases were also observed: Blepharitis, colour blindness, exophthalmos, ocular allergy, strabismus and stye. In the present study many patients were having >1 ocular morbidity, either in the same eye or in the opposite eye. All the multiple ocular diseases found in the same patient were taken as separate diseases. Maximum patients were found in age group 51-60 years (n= 220), out of which 91(41.36%) had refractive errors. No statistically significant findings seen agewise (p value > 0.05). Total 265 males and 235 females were examined. The difference in occurrence of refractive error and cataract between males and females is statistically significant (p value <0.05). In remaining ocular morbidities, no gender wise difference was seen. Table 1: Distribution of ocular morbidities on the basis of residence Ocular morbidty Rural patients (n=218) Urban patients (n=282) P value Refractive errors 83(38.07%) 130(44.5%) 0.0719 Cataract 80(36.6%) 107(37.9%) 0.7752 Dry eye 30(13.7%) 12(4.1%) 0.0001 Retinopathies 8(3.67%) 15(5.32%) 0.3826 Glaucoma 8(3.6%) 9(3.08%) 0.7698 Pterygium 5(2.29%) 9(3.08%) 0.5462 Dacryocystitis 4(1.83%) 6(2.13%) 0.8166* Macular diseases 5(2.29%) 5(1.77%) 0.6801 Entropion/ectropi on 3(1.38%) 6(2.13%) 0.7736* Corneal opacity 4(1.83%) 5(1.77%) 0.9589* Priti Singh et al. Pattern of ocular morbidity amongst patients of elderly age group in Central India Panacea Journal of Medical Sciences, January-April 2018;8(1):34-39 36 The difference in occurrence of dry eye between urban and rural patients is statistically highly significant (p value<0.01) (Table 1). Table 2: Distribution of ocular morbidities on basis of educational status Ocular morbidity Illiterate (n=140) Primary (n=102) Middle (n=110) High (n=63) Graduate &> (n=85) P value R.errors 44(31.4%) 44(43.14%) 54(59%) 31(49.2%) 40(47.06%) 0.028 Cataract 66(47.1%) 42(41.18%) 40(36.3%) 15(23.8%) 24(28.24%) 0.006 Dry eye 26(18.5%) 10(9.8%) 4(3.64%) 1(1.59%) 1(1.18%) <0.001 Retinopathyes 3(2.14%) 4(3.92%) 5(4.55%) 7(11.12%) 4(4.71%) 0.1* Glaucoma 4(2.86%) 3(2.94%) 2(1.82%) 2(3.17%) 6(7.06%) 0.5674* Pterygium 5(3.57%) 3(2.94%) 4(3.6%) _ 2(2.35%) 0.834* Dacryocystits 3(2.14%) 2(1.96%) 3(2.73%) 1(1.59%) 1(1.18%) 0.99* Macular diseases 1(0.71%) _ 1(0.91%) 4(6.35%) 4(4.71%) 0.037* Entopion/ ectropion 2(1.43%) 2(1.96%) 3(2.73%) 2(3.17%) _ 0.975* Corneal opacity 3(2.14%) 3(2.94%) 1(0.91%) _ 2(2.35%) 0.945* The difference in occurrence of refractive error and macular diseases between educational statuses of the patient is statistically significant (p value<0.05) (Table 2). The difference in occurrence of cataract and dry eyes between educational statuses of the patientis is also statistically significant (p value<0.01). Table 3: Distribution of ocular morbidities on basis of socioeconomic statuses Ocular morbidity Upper (n=2) Upper middle (n=130) Lower middle (n=140) Upper lower(95) Lower (133) P value R.errors 1(50%) 70(53.85%) 71(50.7%) 26(27.36%) 45(33.83%) <0.0001 Cataract _ 47(36.15%) 50(35.7%) 38(40%) 52(39.09%) 0.8520 Dry eye _ 1(0.77%) 4(2.8%) 10(10.5%) 27(20.3%) <0.0001# Retinopathies 1(50%) 4(3.08%) 10(7.1%) 3(3.1%) 5(3.7%) 0.399* Glaucoma _ 2(1.53%) 6(4.2%) 3(3.1%) 6(4.5%) 0.516 Pterygium _ 2(1.5%) 6(4.2%) 3(3.1%) 3(2.2%) 0.782* Dacryocystits _ 1(0.77%) 1(0.71%) 6(6.32%) 2(1.51%) 0.0442*# Macular diseases _ 5(3.85%) 1(0.71%) 3(3.1%) 1(0.75%) 0.446* Entopion/ ectropion _ 3(2.31%) 1(0.71%) 4(4.21%) 1(0.75%) 0.444* Corneal opacity _ 2(1.5%) _ 4(4.21%) 3(2.2%) 0.985* Kuppuswamy scale1 was used for urban population and Prasad’s scale8 was used for rural population. The difference in occurrence of dacryocystitis between socioeconomic statuses of the patient is statistically significant. (p value<0.05) The difference in occurrence of refractive errors and dry eyes between socioeconomic statuses of the patient is statistically highly significant. (p value<0.01) (Table 3). Table 4: Distribution of ocular morbidities in hypertensives and diabetics patients Ocular morbidity Hypertensives (n=135) Non-hypertensives (n=365) P value Diabetics (n=62) Non-diabetics (n=438) P value R.errors 50(37.03%) 163 0.1261 19(30.6%) 194 0.042 Cataract 58(42.9%) 129 0.1179 25(40.3%) 162 0.6114 Dry eye 6(4.4%) 36 0.0525 8(12.95%) 34 0.1720 Retinopathies 12(8.8%) 11 0.0054 9(14.5%) 14 0.0001 Glaucoma 8(5.9%) 9 0.0580 4(6.5%) 13 0.2973* Pterygium 2(1.5%) 12 0.4629* 2(3.2%) 12 >0.05* Dacryocystits _ 10 - 2(3.2%) 8 >0.05* Priti Singh et al. Pattern of ocular morbidity amongst patients of elderly age group in Central India Panacea Journal of Medical Sciences, January-April 2018;8(1):34-39 37 Macular diseases 3(2.3%) 7 >0.05* 1(1.6%) 9 >0.05* Entopion/ectr opion 1(0.7%) 8 >0.05* _ _ _ Corneal opacity 1(0.7%) 8 >0.05* 1(1.6%) 8 >0.05* The difference in occurrence of retinopathies between hypertensives and non-hypertensives isstatistically highly significant (p value<0.01). The difference in occurrence of retinopathies between diabetics and non-diabetics is statistically highly significant (p value<0.01). The difference in occurrence of refractive errors between diabetics and non-diabetics is statistically significant (p value<0.05) (Table 4). Table 5: Distribution of ocular morbidities among smokers and non-smokers with tobacco consumption Ocular morbidity Smokers (n=112) Non- smokers (n=388) P value Tobacco Consumption (n=160) No tobacco consumption (n=340) P value R.errors 30(26.8%) 183 0.0001 51(31.9%) 162 0.0009 Cataract 38(33.9%) 149 0.3887 40(25%) 147 0.0001 Dry eye 6(5.3%) 36 0.1875 6(3.75%) 36 0.0101 Retinopathies 6(5.3%) 17 0.6641 1(0.62%) 22 0.0073* Glaucoma 2(1.8%) 15 0.4624* 5(3.125%) 12 0.8159 Pterygium 1(0.9%) 13 >0.05* 2(1.25%) 12 >0.05* Dacryocystits 1(0.9%) 9 >0.05* 2(1.25%) 8 >0.05* Macular diseases 2(1.8%) 8 >0.05* 2(1.25%) 8 >0.05* Entopion/ectropion 1(0.9%) 8 >0.05* _ _ _ Corneal opacity 1(0.9%) 8 >0.05* 1(0.625%) 8 >0.05* The difference in occurrence of refractive errors between smokers and non-smokers is statistically highly significant (p value<0.001). The difference in occurrence of cataract between smokers and non-smokers is statistically significant (p value<0.05). The difference in occurrence of refractive errors, cataract, dry eye and retinopathies between tobacco consumers and non-consumers is statistically highly significant (p value<0.01) (Table 5). Table 6: Distribution of ocular morbidities with cooking fuel use Ocular morbidity Gas cylinder/ stove users (n=455) Smoky chulha users (n=45) P value R.errors 201(44.2%) 12(26.7%) 0.0235 Cataract 166(36.5%) 21(46.7%) 0.1781 Dry eye 38(8.3%) 4(8.8%) 0.9014* Retinopathies 19(4.2%) 4(8.8%) 0.2861* Glaucoma 13(2.9%) 4(8.8%) 0.0894* Pterygium 12(2.6%) 2(4.4%) 0.8202* Dacryocystits 9(1.9%) 1(2.2%) 0.9111* Macular diseases 10(2.2%) _ 0.6106^ Entopion/ ectropion 8(1.7%) 1(2.2%) 0.8233* Corneal opacity 7(1.5%) 2(4.4%) 0.4174* The difference in occurrence of refractive errors between LPG users and biomass fuel users is statisticallysignificant (p value<0.05) (Table 6). Discussion The present study was undertaken in the light of the available literature to determine the prevalence of the different types of ocular morbidities and to study about the risk factors associated with ocular morbidity Priti Singh et al. Pattern of ocular morbidity amongst patients of elderly age group in Central India Panacea Journal of Medical Sciences, January-April 2018;8(1):34-39 38 and prevention of blindness in 500 patients of > 50 years of age. In the present study, the most prevalent ocular morbidities included refractive errors myopia, hypermetropia, astigmatism, aphakia, pseudophakia, and anisometropia. The prevalence was 42.6% that is lesser than found by Agrawal D et al7 in study carried out in an urban population, which might be due to the fact that only patients >50 years were considered in the present study. Refractive errors were most prevalent in the study done by Shrote VK et al8 in the rural area of central India Singh MM et al,3 Rizyal A et al,9 Ukponmwan CU10 but the prevalence was lower as it was carried out in all the age groups. The prevalence of refractive error was found lesser in the studies done by Singh A et al,11 Normalina M et al,12 Khadse A et al,13 Garg Pet al,14 Inaamul Haq et al.15 The second most prevalent ocular morbidity was cataract. Its prevalence rate was 37.4%. It is higher than the studies carried out in an urban population by Agrawal D et al,7 Shrote VK et al,8 Rizyal A et al,9 Ukponmwan CU,10 Khadse A et al,13 Inaamul Haq et al,15 Singh JP et al,16 In the Aravind Comprehensive Eye Survey,17 the prevalence of cataract in those aged 50 years and above was found to be 47.5%. The results in the Blue mountain eye study18 conducted in nursing home residents also shows a higher prevalence of cataract. In the studies done by Singh MM et al,3 Normalina M et al,12 Garg P et al,14 cataract was found to have a higher prevalence. Cataract was found to be most prevalent ocular morbidity (41.89%) in a study done by Singh A et al11 which might be due to the fact that it included only rural population. In the present study prevalence of dry eye was found to be 8.4%. A lower prevalence of 4% was found in the study done by Rizyal A et al9 which might be due to the fact that only patients >50 yrs. were considered in the present study. Howevere a higher prevalence was found by Garg P et al14 and Sahai A et al.19 In the present study prevalence of retinopathies that included diseases like retinal artery occlusion, retinal vein occlusion, diabetic retinopathy, hypertensive retinopathy; was found to be 4.6% slightly higher than found out by Garg P et al.14 A study done by Rizyal et al9 showed the prevalence of diabetic retinopathy to be 1% while that of Ukponmwan CU,10 Normalina M et al,12 and Martinez GS et al20 showed 2.5%, 0.7%, 0.5% respectively. In the present study prevalence of glaucoma irrespective of its type was found to be 3.4%, similar to the results obtained in the studies done by Garg P et al14 and Martinez GS et al20 but is higher than the prevalence found by Agrawal D et al,7 Normalina M et al,12 Khadse A et al13 and Inaamul Haq et al.15 The prevalence of glaucoma was also found to be higher in the studies done by Ukponmwan CU10 and Singh A et al.11 In the present study prevalence of pteygium was found to be 2.8% similar to that found by Khadse A et al13 and is higher than the prevalence found by Agrawal D et al7 in a study conducted in an urban population of Meerut. A slight higher prevalence was found by Ukponmwan CU.10 A study done by Rizyal A et al9 showed the prevalence of both pterygium and pinguecula to be 10.8%. In the studies done by Singh MM et al,3 Normalina M et al12 and Garg P et al14 pteygium was found to have a higher prevalence. In the present study prevalence of dacryocstitis was found to be 2% that is slightly higher than the prevalence found by Agrawal D et al7 and Hussain A et al21 in a study conducted in an urban population of Meerut. The prevalence was lower than that found by Garg P et al.14 We found that prevalence of macular diseases, which consisted primarily of age related macular degeneration (ARMD); cystoid macular edema (CME), traumatic macular edema and macular hole, was found to be 2%. A higher prevalence of maculopathies was found by Ukponmwan CU10 with ARMD’s as 3%. Studies done by Singh MM et al,3 Rizyal A et al,9 Garg P et al,14 Martinez GS et al20 showed the prevalence of ARMD to be 2%, 5.25%, 6.4%,6.89%, and 12.2% respectively. In a study done by Normalina M et al12 none was found to have age related macular degeneration, however drusen were noted. In the present study prevalence of diseases of the eye lids that included entropion and ectropion was found to be 1.8% that is lower than the results found by, Normalina M et al,12 Garg P et al14 and some other studies. In the Blue Mountains Eye Study18 ectropion was found to be higher than the present study. The present study prevalence of the corneal opacity was found to be 1.8% that is higher than the prevalence found by Agrawal D et al7 but lower than the prevalence found in the studies done by Normalina M et al,12 Garg P et al,14 Inaamul Haq et al.15 Thus, the results of the present study correlates with the results found by many studies but also controvert with the results of other studies which may be due to the difference in the design of the present study as compared to other studies or may be significant. The present study was a hospital based cross sectional study that might have caused a higher prevalence of certain diseases. The smaller duration of the study, the seasonal and geographical impact might also have affected the disease prevalence. Many other studies were conducted taking into account the younger as well as older population, while the present study was conducted only in patients of >50yrs; thus was more specific with diseases of elderly and resulted in non-significance of age related increase in prevalence of certain diseases such as cataract. The screening and diagnosing criteria’s might vary from some studies giving different outcome. However utmost care was taken during the whole studydiscrepancies in the results might have occurred due to some reasons. Firstly, the effect of certain factors might have been Priti Singh et al. Pattern of ocular morbidity amongst patients of elderly age group in Central India Panacea Journal of Medical Sciences, January-April 2018;8(1):34-39 39 exaggerated or suppressed by other interactive susceptible factor, both genetic and environmental. Secondly, a low no. of patients in several diseases might have led to the statistical insignificance with the associated factors. Thirdly, there were no control subjects so the risk factors were not studied separately but as combined. Fourthly, the screening and diagnosis of patients some humanitarian errors might be possible. References 1. Park K, editor. Park’s textbook of Preventive and Social Medicine; 22nd ed. Bhanot Publishers, 2015. 2. Chandwani H, Jivarajani P, Jivarajani H. Health and social problems of geriatric population in an urban setting of Gujarat, India. The Internet J Health. 2008;9(2):1-9. 3. Singh MM, Murthy GV, Venkatraman R, Rao SP, Nayar S. A study of ocular morbidity among elderly population in rural area of Central India. Indian J Opthalmol 1997;45: 61-5. 4. Baride JP, Kulkarni AP, editors. Textbook of Community Medicine, 3rd ed. Vora medical publications, 2006. 5. Harrison. Harrisson’s Principles of Internal Medicine, 18th ed. McGraw-Hill Professional;August 11, 2011. 6. Radhika Tandon. Parsons’ Diseases of the eye, 21st ed. Elsevier January 1 2011. 7. Agrawal D, Singh JV, Sharma MK, Mitthal S. Ocular morbidity pattern of an urban population of Meerut. Indian J Prev Med 2011;42(1):74-8. 8. Shrote VK, Thakre SS, Thakre SB, Brahmapurkar KP, Giri VC. Study of some epidemiological determinants of ocular morbid conditions in the rural area of Central India. IOSR JDMS 2012;2(1):34-8. 9. Rizyal A, Shakya S, Shrestha RK, Shrestha S. A study of ocular morbidity of patients attending a satellite clinic in Bhaktapur, Nepal. Nepal Med Coll J. 2010 Jun;12(2):87- 9. 10. Ukponmwan CU. Pattern of ocular morbidity in Nigeria. Asian Pac J Trop Dis 2013;3(2):164-6. 11. Singh A, Dwivedi S, Dabral SB, Bihari V, Rastogi AK, Kumar D. Ocular morbidity in rural areas. Nepal J Ophthalmol 2012;4(7):49-53. 12. Normalina M, Zainal M. The dimensions of ocular morbidity amongst the nursing home geriatrics population. 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Visual impairment 10 nursing home residents: the Blue Mountains Eye Study. MJA 1997;166:73-6. 19. Sahai A, Malik P. Dry eye: Prevalence and attributable risk factors in a hospital –based population. Indian J Ophthalmol 2005 Jun;53(2):87-91. 20. Martinez GS, Campbell AJ, Reinken J, Allan BC. Prevalence of ocular disease in a study of subjects 65 years old and older. Am J Ophthalmol 1982 Aug;94(2):181-9. 21. Hussain A, Awan H, Khan MD. Prevalence of non- vision-impairing conditions in a village in Chakwal district, Punjab, Pakistan. 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