Modality of treatment and potential outcome of Wilson disease in Taiwan: A population-based longitudinal study.

BACKGROUND/PURPOSE: This study aimed to investigate the epidemiology, the preference of medication, and the potential outcome of Wilson disease in Taiwan. We aimed to provide better therapeutic options for patients with Wilson disease based on the data generated from this study.

METHODS: We utilized the National Health Insurance Research Database (NHIRD), which stores clinical records of nearly 99% of Taiwan's residents. The database used is a random sample of two-million out of 23-million beneficiaries in Taiwan's NHIRD in 2005. The integrated medical records of these two-million cases were collected from 2000 to 2011. Subjects of Wilson disease were identified as those with International Classification of Diseases, Ninth Revision (ICD-9) code 275.1 and the specific prescription drugs (including d-penicillamine, zinc, and trientine) in either outpatient clinic or inpatient records.

RESULTS: During the study period, 66 cases of Wilson disease were identified. The male to female ratio was 1.75. The average prevalence rate was 1.81 per 100,000 and the average annual diagnosis rate was 0.22 per 100,000. The diagnosis was mostly established at 20-24 and 10-14 years of age, followed by 25-29 years. Fifty four of all subjects (81.8%) started the treatment with d-penicillamine, compared with zinc (12.1%) and trientine (6.1%). Among these 66 cases, 27 (40.9%) had liver cirrhosis and three (4.5%) underwent liver transplantation due to liver failure.

CONCLUSION: d-penicillamine is still the most popular prescription of Wilson disease, followed by zinc monotherapy. Although chronic liver injury cannot be avoided, a favorable potential outcome is well demonstrated in this population-based study.