KOCHI: Nearly 3 million people above the age of 40 are at risk of blindness due to diabetes in the country, according to an all-India study published in The Lancet. The numbers may even be higher if all people suffering from diabetes are taken into account, says the study, in which researchers from Ernakulam are involved.
While 13% of the Indian population is at risk for diabetic retinopathy, a microvascular complication that can progress without symptoms to visionthreatening diabetic retinopathy (VTDR). In 4% of the population, untreated diabetic retinopathy has resulted in an irreversible visual loss VTDR.
The study was conducted to understand the national and sub-national estimates of the prevalence of diabetic retinopathy and VTDR to decide on the stepwise implementation of systematic retinal screening for people with diabetes in India to decrease the rate of blindness.
“Diabetic retinopathy is the commonest complication of diabetes and a commoncause of visual impairment. However, vision is only affected late in the disease, so retinopathy should be picked up by screening the retina regularly using retinal cameras. Before this publication, there was no India-wide data on prevalence of diabetic retinopathy and in particular, the vision threatening complications,” said corresponding author of the study, Sobha Sivaprasad.
The researchers did a multicentre cross-sectional screening study for diabetic retinopathy, using a complex cluster sampling design in people aged 40 years or older individuals with known andundiagnosed diabetes, in 10 Indian states and one Union Territory between December 2018 and March 2020. Nearly 42,146 participants were screened, of which 19% were identified to have diabetes. Of these, 78% had gradable retinal images.
The study showed that there were no significant differences between urban and rural residence for diabetic retinopathy.
Compared with individuals having undiagnosed diabetes, the study found higher prevalence of diabetic retinopathy and VTDR in individuals with known diabetes, with prevalence being significantly lower in states with low socio demographic index (SDI) and epidemiological transition level (ETL).
While SDI is a composite measure of income per capita, average educational attainment over the age of 15 years and total fertility rate under the age of 25 years for each state, ETL is a ratio of allage disability adjusted lifeyears due to communicable, maternal, neonatal and nutritional diseases versus those due to non-communicable diseases and injuries together.