Link discovered between retinitis pigmentosa and increased risk of primary open-angle glaucoma

Taiwanese researchers reported that patients with retinitis pigmentosa have a significantly greater risk of developing primary angle-closure glaucoma (PACG) than those without retinitis pigmentosa.

Dr Yu-Yen Chen

Dr Man-Chen Hung

Dr Man Chen Hung and Dr Yu Yen Chen from Taichung Veterans General Hospital, Taichung-City, Taiwan, conducted a population-based, retrospective cohort study using the National Health Insurance Research Database to identify patients between January 1, 2001, to December 31, 2011.

Retinitis pigmentosa and primary angle-closure glaucomaare genetic diseases with similar genetic variants and pathophysiology between them. The investigators explained that elevated angle-closure-related intraocular pressure (IOP) may aggregate the visual impairment in patients with retinitis pigmentosa, so they wanted to determine if patients with retinitis pigmentosa have a significantly higher risk of PACG development. This knowledge may facilitate for early intervention in these patients.

More than 6,000 patients with retinitis pigmentosa were identified; almost 25,000 patients served as controls for comparison. retinitis pigmentosa and comparison groups were matched on age and sex.

The mean age of the cohort was 49.0 ± 18.1 years. During the study period, the cumulative incidence of PACG in the retinitis pigmentosa group was significantly higher than in the comparison group (1.61% vs. 0.81%, P < 0.0001). Univariate Cox regression analysis showed that retinitis pigmentosa, age, female sex, hypertension, diabetes mellitus, hyperlipidemia, cataract, and lens subluxation all showed a significantly higher risk of PACG.

After adjusting for age, sex, comorbidities, cataract, and lens subluxation, Drs Hung and Chen found that retinitis pigmentosa still significantly increased the hazard of developing PACG (hazard ratio, 2.04; 95% confidence interval, 1.60–2.59, P < 0.0001).

Based on their findings, the researchers concluded, “This nationwide population-based cohort study showed that people with retinitis pigmentosa are at a significantly greater risk of developing PACG than individuals without retinitis pigmentosa.”