Patient preferences for adverse effects of intraocular pressure-lowering eye drops. Results from a Danish large-scale discrete choice experiment: These adverse effects matter to the patients

Purpose: Assessment of patient preferences for local adverse effects (AEs) of intraocular pressure (IOP)-lowering eye drops. Methods: A total of 10 000 eye drop-treated patients aged 40–75 years were sampled from the Danish national registries. A discrete choice experiment (DCE) was distributed to each patient to elicit preferences for distinct levels of five representative local AE attributes of IOP-lowering drops: acute discomfort, persistent discomfort, blurred vision, non-persistent cosmetic changes, and persistent cosmetic changes. Preference weights were computed using conditional logistic regression and normalised using profile-based normalisation. The mildest severity levels were used as a reference. Heterogeneity analyses were conducted across patient covariates to examine variation in preference patterns. Results: A total of 2445 patients (24% response rate; 55% male; median age: 67 years) completed the DCE, with 2096 providing additional covariate data. 95% reported a diagnosis of glaucoma or ocular hypertension. More females than males reported currently experiencing AEs (48% vs. 35%). 25% had previously discontinued treatment with IOP-lowering eye drops due to AEs. The DCE revealed significant differences in the patients' preferences for avoiding AEs. Severe blurred vision, persistent cosmetic changes, and persistent discomfort exhibited the highest levels of disutility. Moderate acute discomfort and non-persistent cosmetic changes were least important. The patients' preferences varied notably by age and gender. Conclusion: This study provides novel insight into patients' preferences for AEs of IOP-lowering eye drops by identifying the characteristics that most strongly influence treatment choices. These insights support future clinical studies and shared decision-making, facilitating personalised care that can improve adherence, quality of life, and long-term patient outcomes.