The prevalence of blindness and low vision in older onset diabetes mellitus and associated factors: a community-based study

PURPOSE: This community-based study was conducted to assess the prevalence and related factors of low vision and legal blindness in older onset diabetic patients (diagnosed at age 30 and older). METHODS: All known diabetic patients who live in the four primary health care center region Abidinpa?a Ankara, Turkey (total population: 96,348) were included in this cross-sectional study. The prevalence of known diabetes mellitus is 2.2%, of which 96.6% are older onset and 3.4% are younger onset. RESULTS: In the older onset diabetes group (1289 cases), 10.8% of the population had low vision and only 2.7% had legal blindness. Diabetic retinopathy (DR) was observed in 23.6% of the patients with low vision (42% proliferative DR) and in 62.9% of the patients with legal blindness (90.1 % proliferative DR). CONCLUSIONS: In older onset diabetic patients with low vision, nonproliferative retinopathy was a more frequent cause of impaired vision than proliferative retinopathy. Low vision and legal blindness caused by retinopathy were significantly associated with sex, age at examination, age at diagnosis, duration of diabetes, type of diabetes treatment, and hypertension in univariate analysis. However, in logistic regression analysis, low vision and legal blindness caused by retinopathy were found to be associated with longer duration of diabetes (> or =15 years), use of insulin, and hypertension.