Effects and adverse events after CXL for keratoconus are independent of age: a 1-year follow-up study

Purpose To compare the effect, failure rate and the risks of corneal cross-linking (CXL) in keratoconus patients aged ≥ 35 years to patients <35 years. Methods In 141 eyes of 116 keratoconus patients we compared the changes in best phoropter-corrected visual acuity (BCVA) and maximum keratometry values ( K max ) before and 12 months after CLX in patients aged ≥ 35 years ( n =34, 38 eyes) to the cohort of patients below 35 years of age. Results Overall, CXL significantly improved BCVA from 0.487 logMAR (95% confidence interval (CI) 0.426–0.548) by −0.197 logMAR (95% CI −0.243 to −0.150; P <0.001) and reduced K max from 48.96 diopter (Dpt) by −1.33 Dpt (95% CI −1.85 to −0.81: P <0.001). Age ≥ 35 years had no effect on the changes of BCVA (−0.02 (95% CI −0.13 to 0.09); P =0.757) or K max (0.58 (95%CI −0.51 to 1.68); P =0.294) as compared with younger patients. In 54 patients (55 eyes, 38.5%) aged <35 years and in 18 patients (18 eyes, 47.4%) aged ≥ 35 years, BCVA increased by ≥2 Snellen lines. Failure (increase in K max ≥1 Dpt) was observed in 17 eyes (16.5%) of patients aged <35 years and in 3 eyes (7.9%) of patients aged ≥ 35 years during the 12-month follow-up period. Adverse outcomes (loss of ≥2 Snellen lines) occurred in 4 (3.9%) eyes of patients aged <35 years and 1 (2.6%) eye of a patient aged ≥ 35 years. Conclusion Effects and adverse events of CXL treatment do not seem to differ between subjects younger or older than 35 years.