Prevalence of Branch Retinal Vein Occlusion in the Latin Population: Insights Into Clinical Epidemiology

Introduction Branch retinal vein occlusion (BRVO) is the most common form of retinal vein occlusion and a major cause of vision loss. Although its prevalence and clinical features have been well documented globally, epidemiological data from the Mexican population remain limited. Purpose This study aimed to characterize the prevalence, clinical features, risk factors, and complications of BRVO in a Mexican population treated at a tertiary ophthalmology center.  Methodology A retrospective, descriptive, observational study was conducted at the Instituto de Oftalmología Fundación Conde de Valenciana in Mexico City, Mexico. Medical records of patients diagnosed with BRVO between January 2012 and January 2022 were reviewed. Inclusion criteria required a minimum follow-up of six months. Patients with incomplete records or ocular comorbidities other than glaucoma were excluded. Descriptive statistics and subgroup comparisons were performed using IBM SPSS Statistics for Windows, V. 29.0 (IBM Corp., Armonk, NY, USA), with statistical significance set at p < 0.05. Results Out of 1,639 reviewed clinical records, 211 patients met the inclusion criteria, yielding a BRVO prevalence of 2.94 cases per 1,000 patients (0.294%). The mean age was 63 years, and 111 (52.61%) patients were female. Hypertension was present in 96 (45.50%) cases, diabetes was present in 19 (9.00%), and both conditions were present in 33 (15.64%). Glaucoma was found in 35 (16.59%) patients. The most common site of occlusion was the superotemporal quadrant (100 (47.39%)). Complications developed in 163 (77.25%) cases within the first three months, with macular edema (151 (71.56%)) being the most frequent, followed by retinal neovascularization (28 (13.27%)) and neovascular glaucoma (5 (2.37%)). Macular edema was predominantly associated with superotemporal BRVO and often presented within the first month. Macular ischemia was rare (1 (0.47%)) but was associated with poor visual outcomes. Conclusion This study provides the first detailed epidemiological insight into BRVO in a Mexican population, with findings broadly consistent with the international literature. Hypertension and glaucoma were the most common systemic and ocular risk factors, respectively. Macular edema was the leading cause of visual morbidity and developed early in the disease course. These findings underscore the importance of early diagnosis and intervention, particularly in patients with high-risk profiles. Comprehensive systemic evaluation and prompt ocular treatment, especially for macular edema and neovascularization, are essential to optimize visual outcomes and reduce long-term complications.