Effect of age on the development of a latanoprost-induced increase in iris pigmentation

To study the effect of patient age on the incidence of latanoprost-induced increases in iris pigmentation.

Prospective observational observer-masked study.

Thirty-six patients younger than 60 years (group 1) and 36 patients older than 75 years (group 2) with primary open-angle glaucoma.

We photographed both irises of each patient before and 6 months after unilateral latanoprost therapy. The basal iris colors were matched in both groups.

Iris heterochromia identification at the 6-month evaluation of the photographs.

Twenty-eight patients (77.78%) in group 2 developed an increase in iris pigmentation compared with eight patients (22.22%) in group 1 (P = 0.0001, chi-square test).

Age seems to be an important risk factor for latanoprost-induced iris color change.