Delayed treatment in diabetic macular oedema leads to worse vision

Researchers assessed 122 eyes from 100 patients (mean age, 62.1±12.3 years; 63 percent male) with treatment-naïve DMO. Best-corrected visual acuity (BCVA) at baseline was 20/25 or better. Patients were followed every 12 months and data for up to 4 years of follow-up were included in the analysis. Majority of the participants had type 2 diabetes.

Over a median follow-up of 3 years, the researchers found that 51 percent of patients had received treatment during the first follow-up. The median time to presentation to first treatment was 9.5 weeks, such that at the time of intervention the BCVA, expressed as the logarithm of the minimal angle of resolution (logMAR), was 0.22±0.25.

At the first follow-up, linear mixed effects modelling showed that BCVA dropped by an average of 0.046±0.013 logMAR units per year. BCVA at the time of initial treatment was strongly and significantly correlated with the final acuity (p<0.001).

Particularly, each 0.1-logMAR unit lower visual acuity at the time of intervention correlated with a 0.469-logMAR unit drop in the final BCVA. Each week delay in starting therapy also resulted in a significant 0.014-logMAR unit drop in the final vision.

Moreover, the rate of vision deterioration was slower when treatment was given at BCVA 20/25 or better. This is in comparison to eyes that were not treated or were treated when acuity was worse.

Notably, the cumulative number of treatments, including injections or lasers, had no such effect on visual outcomes.