Published online Nov 21, 2017. doi: 10.3748/wjg.v23.i43.7716
Peer-review started: July 30, 2017
First decision: August 29, 2017
Revised: September 25, 2017
Accepted: September 28, 2017
Article in press: September 28, 2017
Published online: November 21, 2017
There are few studies on the epidemiology and natural history of Wilson’s disease in the Chinese population. The authors conducted a territory-based study in Hong Kong (HK) with a population of 7.3 million to address this issue.
Epidemiology data are important for recognizing the temporal trend of a particular disease, understanding the natural history and risk factors, as well as for resource allocation.
To investigate the epidemiology and natural history of Wilson’s disease in the Chinese population.
Data were retrieved from the Clinical Data Analysis and Reporting System (CDARS) and Clinical Management System (CMS) of the Hong Kong Hospital Authority. The study observation period was from 2000 to 2016. Cases of Wilson’s disease between 1999 and 2016 were identified from CDARS by the International Classification of Diseases (ICD)-9 code of 275.1. The incidence rate and prevalence of Wilson’s disease between 2000 and 2016 were calculated. Evaluation of the count data and temporal trends was assessed by Poisson regression model. Cox proportional hazards model was used to identify variables that were associated with adverse outcomes. Kaplan-Meier method was used to analyze the adverse outcomes.
The authors identified 211 patients (male-to-female ratio 0.97:1; median age 27.2 years, IQR: 17.1-38.6 years; median follow-up 8.0 years, IQR: 5.0-14.0 years). The average annual incidence rate and prevalence were 1.44 per million person-years and 17.93 per million, respectively. Between 2000 and 2016, the annual incidence rate decreased from 1.65 to 1.23 per million person-years (Poisson P = 0.010), while the annual prevalence increased from 7.80 to 25.20 per million (Poisson P < 0.001). Among the 176 patients with hepatic involvement, 38 (21.6%) had cirrhosis, three (1.7%) developed hepatocellular carcinoma, 24 (13.6%) underwent liver transplantations, and 26 (14.8%) died. Seven patients had concomitant chronic viral hepatitis B or C. The 5- and 10-year overall survival rates were 92.6% and 89.5%, and for transplant-free survival rates 91.8% and 87.4%, respectively. Cirrhosis and possibly chronic viral hepatitis were associated with poorer overall survival.
There was a considerable increase in the prevalence of Wilson’s disease in the Chinese population. The long-term survival was good except in patients with cirrhosis or concomitant viral hepatitis.
The epidemiology of Wilson’s disease was described in a well defined Chinese population, and factors associated with overall survival and transplant-free survival were identified. Future collaboration with the hepatology units from all public and private hospitals is warranted to allow for an even more precise estimate of the epidemiology of Wilson’s disease and to investigate other potential risk factors for reduced transplant-free survival (e.g., metabolic factors).