Prevalence and causes of avoidable blindness and visual impairment, including the prevalence of diabetic retinopathy in Siwan district of Bihar, India: A population-based survey

Risk of cataract and glaucoma among older persons with diabetes in India: a cross-sectional study based on LASI, Wave-1

According to the International Diabetes Federation-2019 estimates, India is home to 77 million diabetic individuals which is projected to grow up to 147.2 million by 2045. Diabetes being a progressive health disorder leads to multiple morbidities and complications including eye diseases and visual impairments. As the burden of diabetes mellitus is increasing, eye problems like cataracts and glaucoma are commonly cited problems among the older adults. In this context, this study aims to provide the public health evidences on diabetes associated burden and risk of developing cataracts and glaucoma among older adults aged 60 and above in India. The analytical sample of this cross-sectional study comprised of 31,464 individuals aged 60 and above. Bivariate cross-tabulation and chi-square test were performed to understand the differential in the prevalence of cataracts and glaucoma by diabetes mellitus including the socio-economic and demographic characteristics of the individuals. Binary logistic regression estimation was executed to estimate the adjusted odds ratio for each of the outcome variables within a multivariate framework. The cataract problem affects more than one-fifth of the older people, while glaucoma affects 2% of them. The prevalence of cataract and glaucoma is 29% among diabetic older adults compared to 22% among non-diabetic persons. In terms of gender, the cataract prevalence is comparatively higher among females (25%) than males (21%). It is important to note that while adjusting for socio-economic and demographic characteristics, the likelihood of cataract (AOR 1.495; p-value < 0.01) and glaucoma (AOR 1.554; p-value < 0.01) is significantly higher among older adults with diabetes than among their counterparts. Medical practitioners should conduct prognosis for diabetic eye problems among patients and raise awareness about the potential risks of developing vision loss, such as cataracts and glaucoma, which are more prevalent among individuals with diabetes.

The prevalence of vision impairment and blindness among older adults in India: findings from the Longitudinal Ageing Study in India

Vision impairment and blindness are strongly associated with aging and late-life disability. While home to about 17% of the world's population, an estimated 25% of visually impaired people globally live in India. This proportion is expected to increase as India's population rapidly ages and continues to grow. There is a need for up-to-date epidemiologic data on the prevalence of vision impairment and blindness in India and on the socioeconomic determinants of poor vision, especially among older adults, to promote visual and overall health and well-being in later life. This paper uses newly available data from Wave 1 (2017-2019) of the population-based Longitudinal Ageing Study in India to estimate the overall and sex-specific prevalence of presenting visual acuity impairment and blindness among individuals aged 45 and older at the national level and for all constituent states and union territories. Overall, 33.8% (95% confidence interval: 33.31%, 34.26%) of the Indian population aged 45 and older had distance visual acuity impairment or was blind (visual acuity in the better-seeing eye < 20/40). The age-standardized prevalence varied considerably among states (22.3-54.6%), and women were more likely than men to be visually impaired or blind in all states. Near visual acuity impairment was also highly prevalent (43.0%, 95% confidence interval: 42.45%, 43.46%). Vision impairment and blindness were more common among marginalized groups and were associated with lower socioeconomic status. Findings from this study are relevant for surveillance of vision health, design of targeted eye care policies and programs and efforts to promote human and economic development.

Blindness and visual impairment and their causes in India: Results of a nationally representative survey

Introduction

Avoidable blindness is a significant public health problem in India. Nationally representative RAAB surveys (Rapid Assessment of Avoidable Blindness) are being conducted periodically in the country to know the current status of blindness in the country. The current study describes the findings from the RAAB survey conducted during 2015–19 in India.

Methodology

A cross-sectional, population-based survey was conducted across the entire country among persons aged 50 years and above using RAAB version 6 methodology. Presenting and pinhole visual acuity was recorded followed by lens examination using a torchlight. In order to estimate the prevalence of blindness and visual impairment in overall population in India, district weights were assigned to each of the 31 surveyed districts and the prevalence was standardized using the RAAB software.

Results

The overall weighted, age-gender standardized, prevalence of blindness (presenting visual acuity <3/60 in better eye) in population aged ≥50 years was 1.99% (95% CI 1.94%, 2.13%) and of visual impairment (VI) (presenting visual acuity <6/12 in better eye) was 26.68% (95% CI 26.57–27.17%). On multivariate analysis, adjusted odds ratio showed that blindness was associated with age ≥ 80 years (OR = 20.3, 95% CI: 15.6–26.4) and being illiterate (OR = 5.6, 95% CI: 3.6–8.9). Blindness was not found to be significantly associated with either gender or locality.

Conclusion

The results of the survey demonstrate that currently more than one fourth of persons aged 50 years and above are visually impaired (PVA<6/12 in better eye) in India. The prevalence of blindness among them is 1.99%, and older age and illiteracy are significantly associated with blindness. Major causes of blindness included cataract (66.2%), corneal opacity (CO) (8.2%), cataract surgical complications (7.2%), posterior segment disorders (5.9%) and glaucoma (5.5%). The proportion of blindness and visual impairment that is due to avoidable causes include 92.9% and 97.4% respectively.

Prevalence of diabetic retinopathy in urban and rural India: A systematic review and meta-analysis

A systematic review and meta-analysis were conducted to estimate the prevalence of diabetic retinopathy (DR) in India’s urban and rural areas. Medline, Scopus, and ScienceDirect databases were searched for population-based studies published in English between January 1990 and April 2021, wherein the prevalence of DR among Indian residents with type 2 diabetes mellitus (DM) was reported. A random-effects model was used to estimate the overall, rural, and urban prevalence. Data from 10 eligible studies were aggregated for meta-analysis. The prevalence of DR was 17.44% (95% confidence interval [CI], 14.33–20.55) in urban and 14.00% (95% CI: 9.13–18.86) in rural population (P = 0.24). The overall DR prevalence was 16.10% (95% CI: 13.16–24.32), and the population prevalence was 1.63% [95% CI: 0.94–2.32]. Prevalence of DR in people with diabetes was lower in the age group of 40–49 years [13.57% (95% CI: 7.16–19.98)] than in the age group of 50–59 years [16.72% (95% CI: 12.80–20.64)] and the age group of 60 years and above [16.55% (95% CI: 12.09–21.00)]. Variability in studies was high: urban (I² = 88.90%); rural (I² = 92.14%). Pooled estimates indicate a narrow difference in DR prevalence among people with diabetes in rural and urban India. The fast urbanization and increasing diabetes prevalence in rural areas underscore the need for providing equitable eye care at the bottom of the health pyramid.

A multicentric cross-sectional study measuring the equity of cataract surgical services in three high-volume eyecare organizations in North India: Equitable cataract surgical rate as a new indicator

Purpose:

Cataract remains the leading cause of blindness and visual impairment in most low-and middle-income countries, with the greatest burden borne by women. To achieve Global Action Plan targets, cataract programs must target people, especially women, with maximum need. This study examines whether cataract surgical programs in three major north Indian eyecare institutions are equitable and describes a refined indicator for reporting equity.

Methods:

Retrospective one-year cross-sectional study of cataract surgery utilization using routine administrative data from three north Indian eyecare institutions. Patient data were categorized by paying category, sex, and preoperative visual acuity. Comparisons were made between payment categories and sexes.

Results:

Out of the total number of patients operated, 86,230 were in the non-paying category and 56,738 in the paying category. Overall, 8.2% were blind, 21.1% were severely visual impaired (SVI) or worse, and 86.1% were moderate visual impaired (MVI) or worse. Non-paying patients had a significantly higher proportion of poorer visual categories compared to paying patients [(blind, 9.7% vs. 5.8%; SVI or worse, 24.6% vs. 15.8%; and MVI or worse, 89.1% vs. 81.6%, respectively, (P < 0.001)]. Women had significantly higher proportion of poorer visual categories than men [(blind, 8.9% vs. 7.4%, SVI or worse, 21.9% vs. 20.3% and MVI or worse 87.6 vs. 84.7%) (P < 0.001)].

Conclusion:

The institutions primarily provided surgery to patients with maximum need: too poor to pay, low visual acuity, and women. Similar data from all service providers of a region can help estimate the proposed “equitable cataract surgical rate”: the proportion of patients operated with maximum need among those operated in a year. This can be used for targeting people in need.

Situational analysis of diabetic retinopathy screening in India: How has it changed in the last three years?

Of all the eye conditions in the contemporary Indian context, diabetic retinopathy (DR) attracts the maximum attention not just of the eye care fraternity but the entire medical fraternity. Countries are at different stages of evolution in structured DR screening services. In most low and middle income countries, screening is opportunistic, while in most of the high income countries structured population-based DR screening is the established norm. To reduce inequities in access, it is important that all persons with diabetes are provided equal access to DR screening and management services. Such programs have been proven to reverse the magnitude of vision-threatening diabetic retinopathy in countries like England and Scotland. DR screening should not be considered an endpoint in itself but the starting point in a continuum of services for effective management of DR services so that the risk of vision loss can be mitigated. Till recently all DR screening programs in India were opportunistic models where persons with diabetes visiting an eye care facility were screened. Since 2016, with support from International funders, demonstration models integrating DR screening services in the public health system were initiated. These pilots showed that a systematic integrated structured DR screening program is possible in India and need to be scaled up across the country. Many DR screening and referral initiatives have been adversely impacted by the COVID-19 pandemic and advocacy with the government is critical to facilitate continuous sustainable services.

Six years after manual small incision cataract surgery-Perspective from a secondary level eye hospital in Rural India

Purpose:

We assessed the long-term impact of manual small incision cataract surgery (MSICS) in rural Central India using patient reported outcomes (PRO).

Methods:

841 patients undergoing MSICS by a single surgeon from January 2012 to July 2013 were included. The same patients were contacted telephonically in November 2019 and were asked to report their perceived outcome of the cataract surgery. Data on the fellow eye status were also collected. These data were compared with objective data recorded at the time of surgery.

Results:

The mean age was 61.53 ± 10.9 with 59% women. 96% had presenting visual acuity (VA) ≤5/60. 86% had visually significant cataract in the fellow eye; 2.5% were cataract blind. 85% had unaided VA ≥ 6/18 at 6 weeks. 223 patients were contactable by telephone after 6 years. 55 had expired and their relatives gave the information. Of these, 90% reported “good” outcome. PRO at 6 years and unaided VA at 6 weeks after surgery correlated significantly (P = 0.05). 40% had undergone cataract surgery of the fellow eye in the interim. Of those who reported “not good” outcome, 70% had undergone fellow eye surgery, compared with 38% in those who reported “good” outcome (P = 0.005).

Conclusion:

Telephonic PRO correlates with unaided VA 6 years after cataract surgery and could replace a follow-up visit. A PRO of poor vision in the already operated eye was the only factor correlating with fellow eye surgery.

Surgical coverage of cataract in a rural area of north India: A cross-sectional study

Background:

India has the highest number of blind people globally, unoperated cataract being the most common cause of blindness and low vision. Although safe and effective cataract surgical techniques are available, the cataract burden continues to increase annually, due to the backlog of patients to be operated upon, and a growing number of cataract cases due to increased life expectancy.

Aim:

To assess cataract surgical coverage (CSC) in a rural area of north India.

Methods:

A population-based cross-sectional study of CSC among adults (40 years and above) was carried out in two villages of a block in north India using a predesigned questionnaire, visual acuity assessment, and distant direct ophthalmoscopy. Based on the data obtained, CSC (VA <6/60) for both “persons” as well as “eyes” was calculated.

Results:

Overall, CSC (persons) of 43.20% was observed, 29.31% coverage among persons with unilateral cataract and 50.45% among persons with bilateral cataract while CSC (eyes) was found to be 37.14%, being significantly higher (43.56%) among females compared to males (28.21%) (P = 0.012). Around 50% of cataract surgeries were performed in private facilities, 41.35% in government facilities, and rest 8.65% in eye camps. Nearly 90.38% were implanted intraocular lens and 9.62% were non-intraocular lens surgeries.

Conclusions:

Surgical needs for cataract are currently not being met effectively. Reasons for inadequate cataract surgical services need to be sought and addressed to improve the uptake of existing services. Further, reasons for underutilization of government hospitals for cataract surgeries need to be examined.