Study suggests new directions for India’s eye care policy

Researchers found less cataract blindness than generally believed, and early onset of non-cataract blindness may cause greater economic burden.

Much has been said and written about the overwhelming need for cataract services in India, particularly in the nation’s vast rural regions, where most of its people live. The high prevalence of blindness among rural inhabitants is a serious dilemma, and both national and international programs are working to alleviate some of the problem. It is estimated that about one-fourth of the world’s blind and visually impaired people live in India, and that a significant portion of those individuals live in the countryside and are blind due to cataract.

What is far less understood, however, is the burden of moderate visual impairment on India’s formidable urban population. A little more than one-quarter of India’s population live in the cities, and according to a recent study by Lalit Dandona, MD, MPH, the associate director of the L.V. Prasad Eye Institute in Hyderabad in central Southern India, as many as 18.4 million, or 7.2%, of the 255 million urban Indians have untreated, moderate visual impairments that may prevent them from living fully functional lives. The majority of those who suffer from moderate impairment — about 10.9 million — have easily treatable refractive errors that have gone uncorrected due simply to a lack of eyeglasses and of programs to supply them. His ongoing study was published in the March 1999 issue of the journal Ophthalmology. (The same study team also recently published a report in the May 2, 1999 issue of The Lancet which found that 300,000 urban Indians are blind due to uncorrected refractive error.)

Dr. Dandona’s study does not downplay the significance of cataract, which remains a huge problem in India. Rather, the study identifies that there are other prevalent visual problems among urban residents that are even easier and significantly less costly to treat. Given the tremendous prevalence of untreated refractive error, Dr. Dandona and his colleagues are recommending that the Indian health planners may do well to reconsider how visual health programs are funded. Most of the money is targeted for cataract, while other, easier to treat visual health problems might be more effectively addressed.

His proposal, he says, not only helps people with easy-to-fix problems, but may serve as an economic boon to the entire nation. Visual impairment, even minor refractive error, costs money, especially in lost productivity. Dr. Dandona’s team has estimated that the economic loss due to blindness in India was about US$4.4 billion in 1997.

“We do not need to take away the attention from reducing cataract blindness in India. However, we should become smarter and start addressing the other significant causes of blindness and moderate visual impairment as well,” he said.

According to Dr. Dandona of this study is part of a larger effort to assess the visual problems of urban India so that the government may be better equipped to devise and implement effective policies. The Andhra Pradesh Eye Disease Study (APEDS) is a cross-sectional, population-based study of a sample of 10,000 people who represent the population of the southern Indian state of Andhra Pradesh. The study is supported financially by the Hyderabad Eye Research Foundation.

APEDS team members are collecting information from four distinct areas of the state: one urban area — the state capital of Hyderabad, which has a population of 3.5 million, was selected — one relatively well-off rural area, and two poor rural regions. Andhra Pradesh is an ideal location for the study because about one-fourth of its population lives in urban areas, one-fourth in relatively well-off rural areas and one-half in poor rural areas. The distribution of the population of the state approximates that of the entire nation. What physicians glean in Andhra Pradesh could be extrapolated with some degree of accuracy to many other parts of India, Dr. Dandona said.

“Because of the detailed nature of the data being collected in APEDS, we expect that over the next few years reliable information about the various major aspects of blindness and visual impairment will be available to help plan eye care policy here and in other parts of India,” Dr. Dandona told Ocular Surgery News.

Others, however, say that extrapolating the data from Hyderabad to the rest of India is impossible.

“In many towns classified as urban areas, there are no ophthalmologists. Since the paper deals with the prevalence and causes of blindness or untreated conditions that have led to blindness, the service level for eye care is an important factor,” explained G. Venkataswamy, MD, director of Aravind Eye Hospital in Madurai. “Most of the urban population doesn’t enjoy the level of eye care services that are available in large cities like Hyderabad. Therefore, it would not be proper to generalize the findings in Hyderabad to the rest of the country.”

Additionally, there are certain things about Hyderabad that make it unlike the rest of India, according to Dr. Venkataswamy and sources at Aravind.

“The mix of religions in Hyderabad is also not representative of urban India,” he said. “The social and cultural practices are largely determined by the religion.”

For example, social practices such as consanguineous marriages, more common in Hyderabad than in other parts of India, according to Dr. Venkataswamy, may explain the higher rates of genetic-related degenerative conditions like retinitis pigmentosa present there, making it hard to generalize.

Causes of blindness in Hyderabad APEDS found that the city’s 1% blindness rate is caused by the following: Source: APEDS study

One of four

Each sample group in the APEDS study contains about 2,500 participants in each of the four socioeconomic/geographic areas selected. The planning of APEDS took about 8 months. The urban segment reported in Ophthalmology was conducted between October 1996 and June 1997. APEDS’s two rural segments began July 1997, and the last of the rural segments should be completed by the end of this year.

Dr. Dandona explained the objectives of APEDS. “We want to assess a variety of areas through a detailed epidemiological study with an internationally accepted methodology.”

In particular, the APEDS study team is assessing:

• The magnitude and causes of blindness and moderate visual impairment.
• The prevalence of eye diseases.
• The risk factors for eye diseases.
• The barriers to eye care perceived by the people.
• How people’s quality of life is affected by blindness and visual impairment.

The first three objectives of APEDS relate to the “disease” aspect of blindness and visual impairment, and the last two to people’s perceptions of issues related to blindness and visual impairment, Dr. Dandona explained.

“We believe that information on both these aspects is necessary for the planning of an effective eye care policy,” he said. “These data are expected to help plan long-term policy to reduce blindness and visual impairment in Andhra Pradesh and by reasonable extrapolation to other parts of India, as well.”

APEDS revealed that although cataract continues to be a major cause of blindness, previous surveys in India may have overestimated the proportion of blindness caused by cataract.

“Previous surveys did not include a detailed dilated eye examination and visual field assessment,” Dr. Dandona said. APEDS includes a detailed, dilated eye examination and visual field assessment.

In The Lancet study, Dr. Dandona and his team reported that they found that 30% of the blindness in Hyderabad was due to cataract.

“If we had not done detailed, dilated eye examinations and visual fields, we would have erroneously attributed 52% of the blindness to cataract — an overestimation of 75%,” he said.

APEDS’s urban findings

A total of 2,522 people of all ages, including 1,399 persons 30 years of age or older, were selected from 24 clusters representative of the population of Hyderabad city. Subjects underwent a detailed ocular evaluation including logarithm of the minimum angle of resolution, visual acuity, refraction, slit lamp biomicroscopy, applanation tonometry, gonioscopy, cataract grading and stereoscopic dilated fundus evaluation. Automated threshold visual fields and slit lamp and fundus photography were performed when indicated by standardized criteria.

Moderate visual impairment was defined as presenting distance visual acuity of less than 20/40 but better than 20/200, or visual field loss by predefined criteria in the better eye. Blindness was defined as acuity less than 20/200 or central visual less than 10 degrees in the better eye.

In addition to the 1% prevalence of blindness in this sample, moderate visual impairment was present in 303 subjects, an age-and-gender-adjusted prevalence of 7.2%.

The major cause of moderate visual impairment was refractive error, followed by cataract. Visual impairment was significantly higher in those 40 years of age or older and in women. Impairment was generally lower in those belonging to the highest socioeconomic status; however, because of the pyramidal age distribution of the population, 38.1% of the total moderate visual impairment was present in those younger than 40 years of age. The proportion of moderate visual impairment caused by refractive error was higher in the younger than in the older age groups.

Projecting the results of Dr. Dandona’s study to the 26.5% urban population of India, there are 18.4 million people with moderate visual impairment in urban regions alone.

“The eye care policy of India, apart from dealing with blindness, should address the issue of the relatively easily treatable uncorrected refractive error as the cause of moderate visual impairment,” he wrote. About 10.9 million urban dwellers could be easily treated for their visual impairments due to refractive error, but due to a lack of allocated resources and planning, go untreated.

Though APEDS found that urban inhabitants are undertreated when it comes to refraction, some urban Indians and many rural Indians may not be interested in receiving eye care, according to information from Aravind Eye Hospital.

“The need for an individual to go in for glasses will of course depend upon the requirements of the day to day living and the challenges in the work place,” said Dr. Venkataswamy. “Most people in the rural areas engaged primarily in farm work don’t want glasses even when their vision is 20/60 level or less.”

Finding the right track

The need to devise a plan to address eye problems among all Indians was the main reason Dr. Dandona gave for embarking on APEDS. With reliable data, Indian health officials and their partners in the various international non-governmental organizations with health care programs in India could devise better strategies to address vision-health needs.

“We obtained detailed demographic information about the Hyderabad population such that our sample would represent it well,” Dr. Dandona said. Twenty-four clusters of patients were selected from four socioeconomic strata, including extreme lower, lower, middle and upper, mirroring the population of Hyderabad.

Subjects underwent detailed interviews by trained field investigators on demographic background, dietary intake, ocular and systemic history, risk factors for eye diseases, their perception of visual function, quality of life, barriers perceived to obtaining eye care, and knowledge about eye diseases.

They were then brought to a clinic specially set up for APEDS, where one ophthalmologist and two optometrists examined them. The data were collected in standardized pre-tested format, and entered into computer databases for analysis.

What APEDS learned

APEDS discovered that 1% of the population of Hyderabad was blind. The Lancet paper reported that the majority of the blindness occurred in patients older than 30 and that a full 3% of this population group was blind.

The causes of blindness included: cataract (29.7%), retinal disease (17.1%), corneal disease (15.4%), refractive error (12.5%), glaucoma (12.1%) and optic atrophy (11%).

“The interesting thing was that the age of those blind due to causes other than cataract was on average about 14 years younger than those blind due to cataract, suggesting that not only is the blindness due to causes other than cataract not negligible, but it may be causing a high socioeconomic burden since it effects younger people who are more likely to be in the economically productive age group,” Dr. Dandona said. “It made us ask whether the current eye care policy, which focuses almost exclusively on cataract, is adequate to deal with blindness in India.”

The short answer, he and his team would argue, is “no.”

The middle, lower and extreme lower socioeconomic strata in the APEDS study had a similar likelihood of having moderate visual impairment, which was about four times higher than that of the upper socioeconomic stratum.

The approximate socioeconomic profile of the urban Hyderabad population is: upper 10%, middle 45%, lower 35% and extreme lower 10%.

“In contrast, data on blindness in this population suggested that blindness was six times more likely in the extreme lower socioeconomic stratum as compared with the upper or middle strata, and two times more likely in the lower socioeconomic stratum as compared with the upper or middle strata,” Dr. Dandona said.

No formal policy

Dr. Dandona says that formal policy in India for the correction of “very easily treatable” blindness and moderate visual impairment due to refractive error must be created.

“We should start addressing this issue seriously because of the immense burden of this problem, and the ease with which refractive errors can be potentially corrected with spectacles,” he said. “The issue of money for vision programs is a little complicated. Many argue that there is limited money, so in India it should be targeted mostly toward cataract. However, this approach does not seem to have been successful because there is no evidence that the burden of cataract blindness has actually decreased.”

Dr. Dandona believes that the way to bring about long-term reduction of blindness and moderate visual impairment is to invest in permanent, good-quality eye care infrastructure and in high-quality training of eye care professionals.

Current approach is failing

“In fact, India’s current approach to cataract blindness may have actually exacerbated the problem because India’s current eye care policy remains focused on increasing the annual number of cataract surgeries without adequate attention to quality,” Dr. Dandona said.

Of the tools used by the Indian government to increase the annual number of cataract surgeries, surgical eye camps are among the most common — and also the most controversial. Proponents of the camp system note that it is a good way to treat as many patients in as little time as possible. Critics of the systems, however, claim they are too much like surgical assembly lines, where patients receive little postoperative follow-up and where even the most basic rules of surgery are neglected or ignored.

Dr. Dandona claims surgical eye camps have decreased the level of surgical quality in India and may have done more harm than good.

“One of the biggest ironies is that these surgical camps also are conducted in areas, including cities, where eye care facilities are available,” he said. “The reason for this is that with this approach, it is easy to claim credit and reimbursement for a large number of surgeries, either from the government or other non-governmental agencies. The blatant disregard of the basic principles of surgical asepsis and need for postoperative follow-up is most amazing.”

Dr. Dandona suggests that the prevalence of camp surgery has made the Indian health planners less inclined to invest the capital necessary to build a permanent eye care infrastructure where it is needed. There is an illusion, Dr. Dandona said, “that enough is being done through the camp approach, but growing evidence suggests that there is an unacceptably high proportion of people who are blind after cataract surgery in India. In most cases, it is due to a high rate of surgical complications and poor postoperative follow-up.”

Dr. Venkataswamy disagrees. Through the 1,300 eye camps that Aravind organizes each year, more than 300,000 people are evaluated for refractive error, he said.

Calls for more permanent eye care infrastructure are being taken seriously by the Indian government. In fact, on March 31, the government announced a plan to create a permanent eye care infrastructure, phasing out camps, and making IOLs available throughout the country.

“The focus of this program is on the quality of care and follow-up treatment, which will insure better visual outcomes as a sequale to surgery,” said a representative from the Indian Department of Health in a press release.

Although cataract remains the key focus, the move toward permanent facilities is a step in the right direction, Dr. Dandona said.

An alternative

Dr. Dandona and his colleagues are working to open eye care centers in under-served areas that would provide quality eye care services to populations of about half a million people each. These centers would be operated by trained staff and have associated community programs that would seek to increase awareness of preventable causes of blindness, provide early detection and treatment of blindness, provide eye care services such as extracapsular cataract extraction with IOL implant with microscope under standard sterile conditions, and community-based rehabilitation of the incurably blind.

Treatment costs would be based on an ability-to-pay scheme, where the poorest would receive free services, while those with greater wealth would pay more.

“Our initial experience suggests that the running costs of this approach can be recovered from the charges to those who can afford to pay,” Dr. Dandona said. “The point of this is that sustainable long-term good-quality eye care in under-served areas in India should be possible with local resources. Since the government-based approach of reducing blindness in India has not worked well so far, it is time for the poorly-functioning government institutions to be overhauled.”

To deal more effectively with easily treatable visual problems, Dr. Dandona said the government needs to do two things. First, it must work to increase awareness in the population that a large proportion of visual impairment may be easily treatable. Second, it must work to build a quality infrastructure for eye care and make it available to everyone. The work of some non-governmental organizations, he said, could serve as a model.

“Providing eye glasses should be one of the top priorities in the eye care policy,” Dr. Dandona said. “Concurrently, we have to develop a long-term view of dealing with blindness and visual impairment in India by developing strategies to prevent and treat eye diseases that are causing a significant amount of blindness in our country.”

But Dr. Venkataswamy notes that the Indian government is already working to treat refractive error in segments of the population.

“At government level there is a lot of emphasis given to the issue of refractive error.” He said “This is part of a national program to screen school children for visual impairment and provide spectacles at subsidized rates for those with refractive errors.”

In fact, in the Indian state of Tamil Nadu, there has been a vision screening program for children in place for more than 30 years.

“This program, for example, covers about 30% of the population who are in the school-going age,” Dr. Venkataswamy said. “For the other age groups, while no structured program exists, they have good access to refraction services that are offered in the eye camps conducted by [Aravind] and in the base hospitals.”

Cataract still the culprit

At least in the rural population, cataract remains the main cause of blindness, according to Dr. Venkataswamy. A new study by researchers at Aravind, similar to the landmark Baltimore Eye Survey in the United States, found high levels of blindness due to cataract in south India. Some earlier studies showed that even in well-served rural areas, the surgical coverage for cataract is around 30%, while in the rural areas of Tamil Nadu cataract was estimated to account for 70% to 75% of the blindness. Aravind researchers too will soon publish a population-based study of eye sight India.

Report Card: India

Population	985 million
Number of urban citizens	255 million
Number of urban citizens with untreated vision problems	18.4 million
Number of urban citizens with untreated cataract	4.6 million
Estimated annual cost of lost productivity due to vision problems	US$ 4.4 billion

For Your Information:

• For more information on APEDS, contact Lalit Dandona, MD, MPH, at Public Health Ophthalmology Service, L.V. Prasad Eye Institute, L.V. Prasad Marg, Banjara Hills, Hyderabad 50034, India; +(91) 40-354-8267; fax: +(91) 40-354-8271; e-mail: dandona_Dr.Lalit_Dandona/eye@Ivpeye.stph.net.
• G. Venkataswamy, MD, can be contacted at Aravind Eye Hospital, 1 Annanager, Madurai 0625 020, India; +(91) 452-532-653; fax: +(91) 452-530-984; e-mail: dr.v@aravind.org.

Reference:

• Dandona L, Dandona R, Naduvilath TJ, McCarty CA, Srinivas M, Mandal P, Nanda A, Rao GN. Burden of moderate visual impairment in an urban population in southern India. Ophthalmology. 1999;106(3):497–504.