Costs and persistence of carbonic anhydrase inhibitor versus alpha‑2 agonists, associated with beta-blockers, in glaucoma and ocular hypertension: an analysis of the UK‑GPRD database^*

ABSTRACT

Objective: To compare the effectiveness and associated costs of carbonic anhydrase inhibitors + beta-blocker versus alpha‑2 adrenergic agonists + beta-blocker in glaucoma therapy, as documented by The United Kingdom General Practitioner Research Database (UK‑GPRD).

Research Design: Patient chart analysis.

Methods: Patient records were screened for diagnoses of ocular hypertension or glaucoma, and for surgery, laser therapy or medication specific to glaucoma. Selected patients were those prescribed either carbonic anhydrase inhibitors + beta-blocker or alpha‑2 adrenergic agonists + beta-blocker. Treatment failure was defined as a glaucoma prescription change, i.e. addition, cessation or replacement of medication, surgery or laser therapy. Times to treatment failure were compared with an adjusted Cox model.

Main outcome measures: Treatment persistence and cost.

Results: Included patients were those treated with either carbonic anhydrase inhibitors + beta-blocker (n = 5581) or alpha‑2 adrenergic agonists + beta-blocker (n = 1164). The average age at diagnosis was 68.1 years and 48.2% were male. Treatment failure at one year was significantly ( p < 0.001) less frequent after carbonic anhydrase inhibitors + beta-blocker (57% of patients) than after alpha‑2 adrenergic agonists + beta-blocker (64.3%). The hazard ratio for failure was lower (0.82: p < 0.0001) with carbonic anhydrase inhibitors + beta-blocker following adjustment for age, gender, comorbidities and duration of follow-up. Adjusted annual costs of glaucoma management were £348.04 for carbonic anhydrase inhibitors + beta-blocker and £356.80 for alpha‑2 adrenergic agonists + beta-blocker.

Conclusions: According to UK‑GPRD information, glaucoma therapy with carbonic anhydrase inhibitors + beta-blocker is more persistent than with alpha‑2 adrenergic agonists + beta-blocker at a similar cost.

Key words: :

• Alpha‑2 adrenergic agonist
• Beta-blocker
• Carbonic anhydrase inhibitor
• Costs
• Effectiveness
• Glaucoma