Risk factors for four-year incident visual impairment and blindness: the Los Angeles Latino Eye Study

Purpose: To identify independent risk factors for incident visual impairment (VI) and monocular blindness.

Design: Population-based prospective cohort study.

Participants: A total of 4658 Latinos aged 40 years in the Los Angeles Latino Eye Study (LALES).

Methods: A detailed history and comprehensive ophthalmologic examination was performed at baseline and at the 4-year follow-up on 4658 Latinos aged ≥40 years from Los Angeles, California. Incident VI was defined as best-corrected visual acuity (BCVA) of <20/40 and >20/200 in the better-seeing eye at the 4-year follow-up examination in persons who had a BCVA of ≥20/40 in the better-seeing eye at baseline. Incident monocular blindness was defined as BCVA of ≤20/200 in 1 eye at follow-up in persons who had a BCVA >20/200 in both eyes at baseline. Sociodemographic and clinical risk factors identified at the baseline interview and examination and associated with incident VI and loss of vision were determined using multivariable regression. Odds ratios (ORs) were calculated for those variables that were independently associated with VI and monocular blindness.

Main outcome measures: Odds ratios for various risk factors for incident VI and monocular blindness.

Results: Independent risk factors for incident VI were older age (70-79 years, OR 4.8; ≥80 years OR 17.9), unemployment (OR 3.5), and diabetes mellitus (OR 2.2). Independent risk factors for monocular blindness were being retired (OR 3.4) or widowed (OR 3.7) and having diabetes mellitus (OR 2.1) or any ocular disease (OR 5.6) at baseline. Persons with self-reported excellent/good vision were less likely to develop VI or monocular blindness (OR 0.4-0.5).

Conclusions: Our data highlight that older Latinos and Latinos with diabetes mellitus or self-reported eye diseases are at high risk of developing vision loss. Furthermore, being unemployed, widowed, or retired confers an independent risk of monocular blindness. Interventions that prevent, treat, and focus on the modifiable factors may reduce the burden of vision loss in this fastest growing segment of the US population.