Delaying treatment of glaucoma not necessarily harmful

Withholding treatment in individuals with glaucoma does not appear to lead to serious consequences in terms of visual function, according to a study.

For the study, researchers conducted a long-term follow-up of the prospective Early Manifest Glaucoma Trial (EMGT), which was performed at two centres in Sweden, to compare visual outcomes in the trial participants. The analysis included 255 participants with newly diagnosed, untreated glaucoma. They were randomized to undergo immediate treatment with topical betaxolol and argon laser trabeculoplasty or to receive no initial treatment as long as no progression was detected.

The participants were followed for up to 21 years. Assessments included standard automated perimetry, visual acuity measurements, and tonometry. Outcomes were vision impairment, the perimetric mean deviation (MD) index and rate of progression, and visual acuity.

At trial conclusion, the treatment group had a slightly higher percentages of eyes with vision impairment compared with the untreated control group (12.1 percent vs 11.0 percent). The same was true for blindness (9.4. percent vs 6.1 percent, respectively). However, the differences were not statistically significant, nor were cumulative incidences of visual impairment in at least one eye (19.5 percent vs 18.7 percent).

Meanwhile, field loss occurred more frequently in the control group than in the treatment group, with median MD in the worse eye of –14.73 vs –12.85 dB and rate of progression of –0.74 vs –0.60 dB/year. The differences were not statistically significant.

Finally, changes in visual acuity were minimal.