# Prevalence of Diabetes Among First-Time Ophthalmology Patients at a Nonprofit Hospital in Mexico

## TL;DR

This study shows that screening for diabetes among first-time ophthalmology patients in Mexico can significantly improve health outcomes and provide high social returns on investment.

## Contribution

The paper introduces a novel application of the Social Return on Investment (SROI) framework to assess diabetes screening in ophthalmology settings in Mexico.

## Key findings

- 17.2% of first-time ophthalmology patients screened had diabetes, with 20% previously undiagnosed.
- A 9:1 benefit-cost ratio was estimated when considering diabetes treatment costs and patient well-being.

## Abstract

Background/Objectives: Diabetes is Mexico’s second-leading cause of death, primary cause of disability, and diabetic retinopathy (DR) associated with this disease is the leading cause of vision loss among the working population. Limited healthcare funding and inequitable access hinder diagnosis and treatment, leaving 32% undiagnosed and at risk of developing serious complications such as DR. With screening rates declining, nonprofits like the Association to Prevent Blindness in Mexico (APEC) play a crucial role in detecting diabetes and DR, reducing healthcare costs, and improving patient outcomes. Methods: This study analyzes data from over 25,000 first-time patients screened at APEC in 2023, providing a unique empirical resource on diabetes and DR in Mexico. Using the Social Return on Investment (SROI) approach, it evaluates program costs (medical resources, equipment, and personnel) against patient benefits. These benefits are quantified as the probability that newly diagnosed or uncontrolled diabetes patients begin treatment, thus preventing DR, weighted by the Value of Statistical Life (VSL). Results: Of the total screened patients, 17.2% had diabetes. Among them, 20.0% were unaware of their condition, while the remaining 80.0% knew their diagnosis. Notably, 25.8% of those who were aware of their diagnosis did not have diabetes under control. Considering all costs associated with the first-time ophthalmology patients screening program and assuming only a portion of patients would seek treatment, every peso invested by APEC has the potential to generate the equivalent to 542 pesos in patient well-being. When factoring in the subsequent costs of diabetes control treatment borne by the patients, the potential Benefit–Cost Ratio is estimated at 9:1. These results proved consistent to sensitivity analysis for key assumptions affecting the estimated benefits and costs. Conclusions: The study demonstrates that integrating routine diabetes screening into specialized ophthalmologic care can generate substantial social value through timely intervention, as early detection promotes better diabetes management and helps prevent complications beyond diabetic retinopathy.