Refractive Error As a Risk Factor in Patients with Macular Telangiectasia Type 2A: A Case-Control Study

Aim: The purpose of the study was to determine the role of refractive error as a potential risk factor for macular telangiectasia (MacTel) 2A. Subjects and Methods: The study was designed as a hospital-based retrospective case–control study. One hundred and three age- and sex-matched participants served as controls. The study was conducted over a 3-year period (April 2011–March 2014). The diagnosis of MacTel 2A was based on the classification by Gass JD and Blodi BA with the addition of optical coherence tomography and fundus autofluorescence features. Data from medical records were entered in a standardized pro forma and analyzed. Spherical equivalent (SEq) was calculated using the spherical dioptric power plus half the cylindrical dioptric power. Statistical analysis was performed using SPSS version 20 and statistical package R 1386 3.1.0. Results: The mean refractive error (SEq) of the cases was +0.90D and +1.08D among the controls. The refractive errors ranged from −4.00D to +6.75D among the cases. Binary logistic regression analysis was performed to determine the role of refractive error as a risk factor for MacTel 2A. Emmetropia was taken as the reference category. Hypermetropia had an odds ratio (OR) of 2.50 (P = 0.002). Myopia had an OR of 1.50 (P = 0.29). It was inferred that patients with hypermetropia had a 2.50 times higher risk of developing MacTel 2A, compared to emmetropes. Conclusion: Our study of 103 cases and an equal number of age- and sex-matched controls revealed that hypermetropia was a significant risk factor for the development of MacTel 2A.