Comparison of Keratoconus Progression Rate between Adolescents Aged 19-24 Years and Young Adults: Impact on Indication for Crosslinking.

Purpose: To investigate the keratoconus characteristics and progression rate in a patient group of adolescents aged 19-24 years and to compare the results with young adults aged 25-30 years.

Methods: A total of 158 keratoconic eyes (82 and 76 eyes in the adolescent and young adult groups) of the Homburg Keratoconus Center, which were examined by Scheimpflug tomography at least two times, were included in this retrospective study. The visual characteristics, corneal tomography, and biomechanical measurements were noted at the initial visit, 6 months, 12 months, and 24 months after the initial visit. Progression rates and the amounts of change were calculated and compared between groups.

Results: Baseline visual, tomographical, and biomechanical characteristics along with keratoconus staging were similar between groups at the initial visit (p > .05 for all values). Progression rate was 76.8% vs 14.9% with respect to Kmax change, 72.3% vs 12.0% with respect to ABC parameters, and 26.4% vs 16.4% with respect to E staging in the adolescent vs young adult groups, respectively (p < .001, p < .001, and p = .25).

Conclusions: Keratoconus may worsen more rapidly in adolescent patients aged 19-24 years compared to young adult patients aged 25-30 years. This study emphasizes the high progression rate in adolescent patients and the consideration of early cross-linking and/or at least closer follow-ups in this age group.