Establishing a comprehensive national auditory implant registry in Japan: Trends and demographics from the first two years (2023-2024)

To describe the establishment and initial findings of Japan's first comprehensive nationwide registry covering cochlear implants (CIs), active middle ear implants (AMEIs), and bone conduction implants (BCIs), launched in 2023. The registry aims to improve national data collection, support evidence-based policymaking, and track trends in surgical practice and patient demographics.

A web-based electronic data capture (EDC) system was implemented to replace the previous paper-based reporting system. Between January 2023 and December 2024, data were voluntarily submitted by participating facilities across Japan. Collected data included patient demographics, implant types, hearing thresholds, etiologies, and manufacturer information. Registry completeness was assessed by comparison with Japan's National Database of Health Insurance Claims (NDB).

A total of 1880 patients were registered, and 1809 patients with surgical information entered from 104 facilities were selected for analysis, comprising 1723 CI cases and 86 AMEI or BCI cases (11 VSB, 22 BB, 53 Baha). Among 605 pediatric CI recipients, early-age implantation was increasingly observed, with 58 patients (10 %) aged under 1 year and 183 (30 %) aged 1 year. Among adult CI recipients, 271 patients were aged 75 years or older, including 40 patients aged 85 years or older. Additionally, simultaneous bilateral CI surgery was performed in 265 patients, of whom 175 were children, reflecting the expanding indications. Patients with better ear thresholds <90 dB HL accounted for 33 % of adults and 29 % of children. Congenital hearing loss predominated in children, while acquired causes were more common in adults. Among cases with a known etiology, hereditary deafness was the most common (24.5 %), although 39.6 % of etiologies were unknown. CI data completeness reached 73 % compared with NDB, indicating strong nationwide participation and a high level of data reliability.

This is the first comprehensive report from the national registry in Japan that includes not only CIs but also AMEIs and BCIs. The registry demonstrated reliable data capture and highlighted important trends in patient demographics and surgical practices. Continued data collection will enhance clinical decision-making and support policy development, ultimately improving care for auditory implant recipients.