Publication date: Jul 16, 2026
The COVID-19 pandemic disrupted routine healthcare delivery worldwide. For patients with chronic conditions requiring lifelong therapy, such as glaucoma, this disruption threatened continuity of care. We aimed to quantify the pandemic’s impact on medication adherence and persistence using a large Italian administrative database. We conducted a retrospective cohort study using healthcare databases from Lombardy, Italy. Established patients with glaucoma (defined as ≥ 6 dispensations of ATC S01E medications with a glaucoma diagnosis) were identified in two time periods: 2017 (2018 Cohort, followed from March 2018 before the pandemic) and 2019 (2020 Cohort, followed from March 2020 at pandemic onset). Newly diagnosed patients had no glaucoma therapy in the preceding year. For the primary persistence analysis, follow-up was restricted to 24 months to avoid contamination of the 2018 cohort by pandemic exposure. Persistence was defined as continuous prescription refills allowing a 90-day grace period. Adherence was measured using the Medication Possession Ratio (MPR), with ≥ 80% defined as adherent. We used Cox proportional hazards models and chi-square tests for comparisons. Among 111,373 established patients, the risk of discontinuation was significantly higher during the pandemic (adjusted HR 1. 17, 95% CI 1. 15-1. 18; p
| Concepts | Keywords |
|---|---|
| Adherence | |
| COVID-19 | |
| Glaucoma | |
| Persistence | |
| Real-world evidence | |
| Sustained-release drug delivery |
Semantics
| Type | Source | Name |
|---|---|---|
| disease | MESH | COVID-19 Pandemic |
| disease | MESH | Glaucoma |
| drug | DRUGBANK | Timonacic |
| pathway | REACTOME | Release |