Objective Proteoglycans and glycosoaminoglycans play many roles in connective tissue formation, their accumulation in myxomatous tissues may influence the associated mechanical behaviour of the mitral valve, as well as the extracellular matrix of the eye. Open-angle glaucoma (OAG) and mitral valve prolapse (MVP) may share similar phathophysiology. We hypothesised that MVP increased the risk of developing glaucoma.

Methods The research was a retrospective cohort study using a longitudinal health insurance database from the National Health Insurance programme. The database was a randomly sampled population of 1 073 891 followed for 13 years from 1996 to 2008. There were 21 677 subjects with MVP, and 86 708 subjects without MVP were propensity score matched and served as a comparison group. Cox proportional hazards analysis was performed and adjusted for several comorbidities to evaluate the adjusted HR for OAG in the MVP group.

Results The incidence rate of OAG in patients in the non-MVP and MVP groups were 10.17 and 16.05 per 10 000 person-years, respectively. The adjusted HR for OAG in the MVP group was 1.88 (95% CI 1.58 to 2.23). A significantly elevated risk of OAG in patients with MVP was also identified in the four stratified age groups. The cumulative incidence of OAG was assessed by Kaplan–Meier analysis. The analysis revealed that the MVP group had a higher incidence of OAG than the comparison group during the follow-up period (p<0.001).

Conclusions This population-based study demonstrated that pre-existing MVP is a significant predictor for the development of OAG, after adjusting for possible confounding factors.