Free Screening for Diabetic Retinopathy Is Cost Effective

February 23, 2012 (Abu Dhabi, United Arab Emirates) — According to an analysis performed at the University of Hong Kong, offering patients with diabetes free screening for diabetic retinopathy is the most cost-effective screening approach for identifying patients with signs of that complication.

Results from the analysis, which used a cost/benefit threshold of approximately US$13,000 per quality-adjusted life-year (QALY) gained, were reported here at the World Ophthalmology Congress 2012.

"Diabetic retinopathy accounts for 4.8% of the 37 million cases of blindness globally," said Rita Gangwani, MD, FRCDEd, from the Eye Institute at the University of Hong Kong, who was one of the investigators who performed the analysis. "It is even the leading cause of blindness in working-age groups in the affluent United States, so we know that screening is worthwhile, but cost effectiveness needs to be determined."

The objective of the study was to determine the number of sight years saved and the QALYs gained with screening.

Dr. Gangwani's team created a decision-analysis model that incorporated 3 screening methods: digital retinal fundus photography performed by an optometrist that required a copay of approximately US$10; the same screen by an optometrist offered at no cost to the patient; and opportunistic screening, with visual acuity determined by ophthalmoscope and performed by a general practitioner and/or nurse as part of a routine examination of the patient with diabetes.

The costs of screening were derived from averaged costs of local procedures (direct costs). Costs related to diabetic retinopathy progression and treatment were stratified by the severity of the retinopathy. Indirect costs, such as the loss of productivity and travel costs incurred with screening, were included in the model.

The decision-analysis model was iterated for a hypothetical cohort of 1000 patients with diabetes.

"Free systematic retinopathy screening was the most effective of the 3 strategies," despite having a third-party payer absorb the full cost of retinopathy screening, reported Dr. Gangwani. "It was the most cost-effective option if willingness to pay was [US$16,000] per QALY gained."

Not surprisingly, the hit-and-miss strategy of opportunistic screening was the least cost-effective method, resulting in 549 sight years saved and 170 QALYs gained at a screening cost of approximately US$500,000.

The copay method was the second most cost-effective method, resulting in 845 sight years saved and 262 QALYs gained at a cost of approximately US$786,000.

The most cost-effective method — free screening — resulted in 15 extra sight years and 5 extra QALYs gained over the copay method, at an additional cost of approximately US$64,500.

"According to the [World Health Organization], any procedure that can gain an extra QALY at a cost of 1 times the annual per capita gross domestic product (in this case, US$43,500) is very cost effective," said Dr. Gangwani. The results of this analysis place the cost per QALY for free screening at approximately US$13,000.

"This is a quite low value from a payer perspective, so for Hong Kong, we should ideally offer free screening for diabetic retinopathy."

Diabetes Prevalence Increasing

The issue of how to address the current global diabetes epidemic is a rapidly growing concern in the Middle East, said Emae Badawi, MD, from the Department of Ophthalmology, King Hamad University Hospital, Bahrain, who was trained at Georgetown University in Washington, DC.

"The problem is the adoption of the Western lifestyle. People now drive everywhere, we have the same fast food as any Western country, and stress levels are up with expanding work hours," Dr. Badawi explained. He is also concerned about the age of his patients with diabetes. "It used to be individuals who were 50 years of age and older. Now I see diabetic patients in their 30s."

Implied in this observation is a coming explosion in the number of cases of diabetes-related retinopathy as the population ages, Dr. Badawi noted, leaving healthcare systems worldwide the choice of finding ways to pay for cost-effective screening or waiting to deal with the costs, and lost productivity, of the patient with failing eyesight as a result of diabetic retinopathy.

There are reported conflicting financial interests related to this presentation.

World Ophthalmology Congress (WOC) 2012: Abstract FP-EPI-SA 221 (7). Presented February 18, 2011.