Seven decades of clinical experience with Wilson's disease: Report from the national reference centre in Poland

Background and purpose: Wilson's disease (WD) is a rare autosomal recessive disorder causing excessive copper deposition and a spectrum of manifestations, particularly neurological and hepatic symptoms. We analysed the clinical characteristics of patients with WD admitted to the country's only reference centre, which provided long-term care to most adult patients in Poland over seven decades (pre-1959 to 2019). Methods: Electronic prospective data collection began in the 2000s and, for prior years, medical records were analysed retrospectively. Demographic and clinical characteristics, treatment and outcomes were analysed by decade of diagnosis. Life-years lost were estimated in patients with WD compared with the general population. Kaplan-Meier curves were used for a time-to-death analysis using 2000-2009 as a reference. Results: In total, 929 patients were analysed. The number of patients increased from 21 before 1959 to 315 for 2000 to 2009 period. Mostly males were diagnosed before the 1990s, but the numbers of female patients diagnosed increased thereafter. Initially, most patients presented with neurological manifestations; however, the incidence of hepatic manifestations and asymptomatic presentations increased over time as patients were diagnosed early and consequently were more independent at diagnosis. Fewer Kayser-Fleischer rings were detected recently. Prior to 1970, patients were treated with D-penicillamine (DP); however, since the introduction of zinc, both therapies have been used as often. Since the 1990s, switches between DP and zinc were recorded in 6%-7% of patients. Consistent improvement in survival has been observed over the years. Conclusions: This is the largest cohort of patients with WD reported in Poland, with the longest follow-up. Earlier diagnosis and prognosis have improved over seven decades.