A cataract is the principal cause of blindness for people above 50 years in India, according to the National Blindness and Visual Impairment Survey of India (2015-19), adding that barriers to accessing treatment include the following — no one to accompany [the patient], seasonal preferences, and financial constraints. National Blindness and Visual Impairment Survey:

  • The survey was conducted by Dr Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, over a three-year period, between 2015 and 2018 for Union Ministry of Health and Family Welfare.
  • The survey was conducted in 31 districts of 24 States in the country.
  • A Rapid Assessment Avoidable of Blindness (RAAB-6) methodology was used to conduct the survey.
Rapid Assessment Avoidable of Blindness(RAAB-6):
  • RAAB-6 is a widely accepted method which is being used worldwide to detect the prevalence of blindness in people above 50 years of age.
Key Facts:
  • Among men, the most important barriers are financial constraints (31%) and local reasons (21.5%).
  • Among women, local reasons (23.1%) and financial constraints (21.2%) were the most important barriers.
  • A cataract is a cause for 66.2% cases of blindness, 80.7% of cases of severe visual impairment, and 70.2% cases of moderate visual impairment in the age group.
  • Also, blindness is more pronounced among illiterate (3.23%) than literates (0.43%) and more prevalent in the rural population (2.14%) than urban (1.80%).
  • According to the survey, the financial constraint was found to be the biggest barrier in accessing a cataract surgery with this being a reason for 22.1% blindness cases and lack of awareness was behind 18.4% cases, who did not feel any need of the surgery.
  • Inside human eyes, there is a natural lens. The lens bends (refracts) light rays that come into the eye to help us see.
  • A person with cataract, this lens becomes cloudy, and vision gets blurry, hazy or less colourful.
Cataract Major Cause Of Blindness Above 50
  • A cataract may be characterised by:
    • Blurry vision
    • Seeing double (when you see two images instead of one)
    • Being extra sensitive to light
    • Having trouble seeing well at night, or needing more light when you read
    • Seeing bright colours as faded or yellow instead
  • Ageing is the most common cause. At the age of 40 years, the normal proteins in the lens start to break down. This is what causes the lens to get cloudy.
  • Having certain medical problems, such as diabetes
  • An eye injury, eye surgery, or radiation treatments.
  • Having spent a lot of time in the sun, especially exposure to damaging ultraviolet (UV) rays
  • Using certain medications such as corticosteroids, which may cause the early formation of cataracts.
  • Surgery is the only option if vision is totally blocked due to cataract. If not, then symptoms can be treated by remedies like stronger eyeglasses, magnifying lenses, or sunglasses with an anti-glare coating.
Government intervention: National Programme for Control of Blindness and Visual Impairment (NPCB&VI) 
  • National Programme for Control of Blindness and Visual Impairment (NPCB&VI) was launched in the year 1976 with the goal of reducing the prevalence of blindness to 0.3% by 2020.  
  • Rapid Survey on Avoidable Blindness conducted under NPCB during 2006-07 showed a reduction in the prevalence of blindness from 1.1% (2001-02) to 1% (2006-07).
  • Prevalence of Blindness target -  0.3% (by the year 2020).
Major Causes of blindness 
  • Cataract (62.6%)
  • Refractive Error (19.70%) 
  • Corneal Blindness (0.90%), 
  • Glaucoma (5.80%), 
  • Surgical Complication (1.20%) 
  • Posterior Capsular Opacification (0.90%) 
  • Posterior Segment Disorder (4.70%), 
  • Others (4.19%) 
Main objectives
  • To reduce the backlog of avoidable blindness through identification and treatment of curable blind at primary, secondary and tertiary levels, based on an assessment of the overall burden of visual impairment in the country;
  • Develop and strengthen the strategy of NPCB for “Eye Health for All” and prevention of visual impairment; through the provision of comprehensive universal eye-care services and quality service delivery;
  • Strengthening and up-gradation of Regional Institutes of Ophthalmology (RIOs) to become the centre of excellence in various sub-specialities of ophthalmology and also other partners like Medical College, District Hospitals, Sub-district Hospitals, Vision Centres, NGO Eye Hospitals; 
  • Strengthening the existing infrastructure facilities and developing additional human resources for providing high-quality comprehensive Eye Care  in all Districts of the country;
  • To enhance  community awareness on eye care and lay stress on preventive measures; 
  • Increase and expand research for prevention of blindness and visual impairment;
  • To secure the participation of Voluntary Organizations/Private Practitioners in delivering eye care.
Also read: Sagittarius A* I What is Sagittarius A*? A Fourth Of Indians Consider Dementia To Be Dangerous