DR blindness not caused by DR

Visual loss in subjects with diabetic retinopathy (DR) is caused by factors other than the disease, according to study results published in the September issue of Investigative Ophthalmology & Visual Science.

Lohrasb Ahmadian, MD, MPH, MSc, and Robert Massof, PhD, FAAO of the Lions Vision Research and Rehabilitation Center, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, US conducted a retrospective study assessing reading, mobility, visual motor and visual information processing. For each of these metrics, the researchers monitored the results from DR patients (n=114) and case-matched them with those of patients suffering from other ocular diseases (n=114) who were of an equivalent age (19–90 years; mean, 67.5), visual acuity (VA; mean, 0.7 logMAR), gender and general health.

After adjusting for multiple comparisons, the researchers found no statistically significant difference in any of the four metrics for the matched pairs. There was, moreover, no statistically significant difference between matched pairs when comparing two further parameters: goal-level vision-related functional ability and total visual ability.

The researchers concluded that the disease process itself is not the root cause of visual impairment in DR subjects, and that it is more likely that the visual impairment that these patients experience is caused by the impact of the disease in their daily lives.