The Charles Bonnet Syndrome in Patients With Neovascular Age-Related Macular Degeneration: Association With Proton Pump Inhibitors.

Purpose: We investigate the prevalence of the Charles Bonnet syndrome (CBS) in patients with neovascular age-related macular degeneration (AMD) and analyze the role of oral proton pump inhibitors (PPIs) and other potential risk factors.

Methods: A total of 510 consecutive patients with neovascular-AMD followed at a single tertiary center in Portugal were screened for CBS. Using a structured questionnaire, psychiatrically healthy individuals were interviewed systematically and divided into a CBS group and a non-CBS group. Demographic data, current medication, and ocular risk factors were collected and compared between the two groups.

Results: A total of 500 patients met the inclusion criteria and 471 with complete data were included in the final analysis. The prevalence of CBS was 9.0% (45/500). Using a binary logistic regression model, correlations were found between older age (P = 0.002), PPI intake (P = 0.022), poor visual acuity (P = 0.004), and development of CBS. PPIs doubled the risk of CBS from 7% (20/304) to 15% (25/167), with an odds ratio of 2.154. The increased risk for visual hallucinations caused by PPIs was independent of age (P = 0.598) and visual acuity (P = 0.739).

Conclusions: The prevalence of CBS in neovascular-AMD patients is high and mainly affects older individuals with poor visual acuity. PPIs seem to increase the risk of development of hallucinations independently of the degree of visual loss.