Refractive Errors and Ocular Morbidity Among Commercial Drivers in North Delhi: A Cross-Sectional Study

Abstract

Background: Visual impairment poses a significant global public health concern, with substantial implications for road safety. Refractive errors are a leading cause of visual impairment worldwide, and their impact on commercial drivers, who require optimal vision for safe operation of vehicles, warrants specific attention. Road traffic injuries are a major cause of mortality and morbidity globally, and visual impairment is recognized as a contributing risk factor. While studies have examined the prevalence of visual impairment in various populations in India, data specific to commercial drivers in North Delhi remain limited.

Methods: A descriptive cross-sectional study was conducted between December 2023 and March 2024 to screen commercial heavy-vehicle drivers at mobile eye camps stationed in key truck-parking locations across North Delhi. Using convenience sampling, 2,541 licensed drivers were enrolled. Comprehensive eye examinations were carried out by a trained optometrist, including monocular visual acuity assessment with logMAR charts, both objective and subjective refraction, objective refraction, fundus photography, and color vision testing. Refractive errors were defined as myopia of ≤ –0.50 diopters (D), hyperopia of ≥ +0.50 D, or astigmatism with a cylindrical error of ≥ 0.50 D. Presbyopia was identified as near vision worse than N6 at 40 cm that required an addition of at least +1.00 D. Drivers diagnosed with uncorrected refractive errors were provided with spectacles at no cost. Data were analyzed using Microsoft Excel 2013, and prevalence estimates were reported with corresponding 95% confidence intervals (CIs)

Results: The study population had a mean age of 38.7 ± 8.9 years (range: 18–60 years), with 99% identifying as male. The overall prevalence of uncorrected refractive errors (ametropia) was 9.9% (252 out of 2,541; 95% CI: 8.8–11.1). Among these, astigmatism was the most prevalent (5.03%), followed by hyperopia (3.97%) and myopia (0.90%). Presbyopia was observed in 42.7% of participants (1,084/2,541), with a significant age-related increase noted beyond 40 years (p < 0.001). Regarding ocular morbidity, cataract emerged as the most common pathology (2.79%), followed by retinal abnormalities (0.47%) and suspected glaucoma cases (0.19%). Despite these findings, only 14% of drivers reported ever having undergone an eye examination. Among those identified with refractive errors and offered corrective lenses, 91% accepted and received spectacles.

Conclusion: Uncorrected refractive errors affected approximately one in ten commercial drivers in North Delhi, and presbyopia was present in more than 40% of the cohort. Additionally, a notable proportion exhibited potentially sight-threatening ocular conditions. Implementing mobile eye screening programs with immediate on-site spectacle provision proves to be an effective approach for enhancing visual health and potentially improving road safety within this high-risk occupational population.