As tears are not produced sufficiently in people who are aqueous deficient, it is a more dangerous from of dry eye disease. They have severe clinical disease, say Dr. Sayan Basu (left) and Dr. Pragnya Rao Donthineni.

Incidence of dry eye disease in India is about 1.9 million. The prevalence of dry eye disease will be about 40% of the urban population by 2030. Men get it as early as in their 20s and 30s while women get it in their 50s and 60s. Dry eye disease caused due to inadequate tear production may be due to an underlying autoimmune disease which has to be investigated.

For the first time, a large-scale, hospital-based study in India involving over 14.5 lakh patients had found the incidence (number of new cases occurring each year) of dry eye disease to be 21,000 (1.46%). At over 12,500 cases, the incidence in urban areas was higher than in rural areas (over 8,700 cases). With a large aging population, growing middle-class, and chronic nature of the disease, India is on the verge of a dry eye disease epidemic, the study says. If extrapolated, the incidence at 1.46% translates into nearly 1.9 million across India. The prevalence of dry eye disease will be about 40% of the urban population by 2030.

Moderate dry eye disease

Since the disease tends to be progressive with age, once corneal damage becomes irreversible it can lead to visual impairment and even blindness. Early diagnosis and treatment is therefore important. Dry eye disease is hugely underdiagnosed in India.

The study was undertaken across 200 locations including village and cities in four States (Telangana, Andhra Pradesh, Orissa and Karnataka) between 2010 and 2018. The results were published in the journal The Ocular Surface.

Severe dry eye disease.

The study found the onset of dry eye disease is early in men than in women. In men, the age of disease onset is as early 20s and 30s compared with 50s and 60s in women. Hormonal imbalance could be a likely reason for higher dry eye disease in women in their 50s and 60s. “This is first study that has shown an age-based gender risk for the disease,” said Dr. Sayan Basu from LV Prasad Eye Institute, Hyderabad.

Age, urban residence, occupation and socio-economic affluence were found to be high risk-factors for developing dry eye disease.

Dry eye disease could occur due to inadequate tear production (aqueous deficient), tear film instability due to evaporation or mixed type. Over 20.5% had dry eye disease caused by inadequate tear production, 35.5% due to tear film instability (evaporative) and 40% being mixed. “As tears are not produced sufficiently in people who are aqueous deficient, it is a more dangerous form of dry eye disease. They have severe clinical disease,” said Dr. Pragnya Rao Donthineni from LV Prasad Eye Institute, Hyderabad. “There is a possible underlying autoimmune disease which is causing inadequate tear production and this has to be investigated.”

“Testing the tear volume is mandatory for all patients with dry eye disease. Only this test will tell if the disease is evaporative [tear film instability], aqueous deficient or mixed and treated accordingly,” said Dr. Basu. Reducing the amount of time spent on mobile phones and computer, taking a break every 30 minutes, and certain eye exercises can help prevent dry eye diseases.

Published in The Hindu on March 18, 2019