Identifying facility-level and infrastructure-level bottlenecks in Japan's lecanemab rollout through an online survey of dementia specialists.

Background: The approval of lecanemab has created new operational demands for Alzheimer's disease care. Japan's nationwide rollout under universal health insurance offers an opportunity to identify real-world bottlenecks in treatment delivery. Objective: To identify facility-level and infrastructure-level factors associated with wait time to initial lecanemab infusion and treated patient volume among dementia specialists in Japan. Methods: We performed a secondary analysis of an anonymous online survey of 296 dementia specialists certified to prescribe lecanemab in Japan approximately one year after approval. We examined associations between physician/facility characteristics, diagnostic and infusion resources, perceived implementation barriers, and two delivery metrics: wait time from first consultation to first infusion and number of treated patients per respondent. Bayesian accelerated failure-time and zero-truncated Poisson mixed-effects models were used. Results: Approximately 80% of respondents reported average wait times of 3 months or less, whereas the median treated caseload was modest at 5 patients per physician. Perceived mismatch between treatment capacity and demand was associated with longer wait time (time ratio 1.323, 95% credible interval 1.045-1.682). Cerebrospinal fluid (CSF)-dominant amyloid-testing strategies tended to be associated with smaller caseloads, while in-house CSF testing and Conclusions: Japan's rollout may be constrained by some bottlenecks in diagnostics, infusion infrastructure, and uncompensated tasks. Appropriate policy interventions might help secure equitable access to the treatment.