Physician awareness and understanding of chronic inflammatory demyelinating polyradiculoneuropathy in Japan: a web-based study

Objectives: To investigate potential knowledge gaps between neurologists and non-specialists and identify challenges in the current management of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), with a focus on 'early diagnosis' and 'appropriate treatment' for CIDP.

Design: A non-interventional, cross-sectional, web-based quantitative survey of physicians working in healthcare clinics or hospitals in Japan.

Setting: Participants were recruited from the Nikkei Business Publications panel from 18 August to 14 September 2022.

Participants: Responses from 360 physicians (120 each of internists, orthopaedists and neurologists) were collected.

Outcome measures: Responses relating to a CIDP hypothetical case and current understanding were assessed to determine awareness, collaboration preferences and diagnosis and treatment decisions.

Results: Understanding of CIDP was 90.8% among neurologists, 10.8% among orthopaedists and 13.3% among internists; >80% of orthopaedists and internists answered that neurologists are preferable for treatment. Diagnostic assessment using a hypothetical case showed 95.0% of neurologists, 74.2% of orthopaedists and 72.5% of internists suspected CIDP. Among orthopaedists and internists suspecting CIDP, >70% considered referring to neurology, while ~10% considered continuing treatment without a referral. Among neurologists, 69.4% chose intravenous immunoglobulin (IVIg) as first-line treatment and determined effectiveness to be ≤3 months.

Conclusions: Orthopaedists and internists had lower CIDP awareness compared with neurologists, which may lead to inadequate referrals to neurology. Evaluation of IVIg effectiveness for maintenance therapy occurred earlier than the guideline recommendations (6-12 months), risking premature discontinuation. Improving CIDP knowledge among orthopaedists and internists is critical for better diagnosis and collaboration with neurologists. Neurologists should consider slow and careful evaluation of IVIg maintenance therapy.

Trial registration number: UMIN000048516.