Clinical phenomenology and mortality in Charles Bonnet syndrome

Background/Aim: Despite existing diagnostic criteria for Charles Bonnet syndrome (CBS), clinical manifestations vary greatly. We examined the clinical course and mortality of patients diagnosed with CBS. Methods: We conducted a retrospective chart review of patients with CBS. We collected demographic and clinical information and medical burden scores. Kaplan-Meier mortality curves were compared using log-rank test. Cox proportional hazard model was used for multivariate analysis and hazard ratio (HR). Mortality was compared to expected mortality from Minnesota population. Results: Seventy-seven patients with CBS had a mean age of 79.5 (standard deviation + 13.0) and were predominantly Caucasian (97%) and female (73%). In all, 20 (26%) subsequently developed a dementia syndrome, most often Lewy body. A total of 46 (60%) deaths occurred with an average follow-up time of 33.0 months. Characteristics associated with mortality included older age (75-84 [HR 3.34, P = .029], >85 [HR 4.58, P = .007]) and renal disease (HR 3.39 with 95% confidence interval 1.31-8.80, P = .012). Medical burden scores were not associated with overall mortality. Mortality was high compared to Minnesota population (P < .0001). Conclusions: A large proportion of patients with CBS developed dementia, and there was a high mortality rate associated with older age and renal disease. Medical burden was not associated with mortality.