This clinical, prospective study aims to evaluate the usefulness of electronically captured wearable data to assess disease activity in CIDP (chronic inflammatory demyelinating polyneuropathy) patients undergoing IVIG treatment. Close clinical monitoring will complement smartwatch-acquired data to shed light on different patient clusters and end-of-dose phenomena.

CIDP is a rare chronic neurological condition that leads to a considerable patient burden. As symptoms are often challenging to monitor, finding an individually optimal treatment regimen can be challenging. Additionally, patients receiving treatment often describe individual end-of-dose-phenomena, frequently leading to uncertainty regarding treatment intervals. Digital smartwatch-based measurements could add high-frequency real-world data to the picture and thus improve the understanding of individual disease courses.

Consequently, this study aims to evaluate different digital measurements and blood-based analyses to monitor disease activity in CIDP patients treated with intravenous immunoglobulins. Firstly, digital and blood-based measures will be compared to subjective patient reports and established clinical scores. Secondly, explorative analyses will aim to understand the longitudinal disease course and fluctuations thereof.

Data captured by the used smartwatches (Withings Scanwatch) includes activity-related data (step count, minutes in certain intensity levels), basic cardiovascular measurements such as heart rate, and sleep-related data (total time asleep, sleep quality, etc.). Blood-based measurements include serum neurofilament-light-chain (sNfL), glial fibrillary acidic protein (GFAP) and proteomic data. The investigators aim is to show can show whether therapy-dependent activity patterns, such as the end-of-dose phenomenon, are reflected in the recorded data.

Optionally, the digital signatures of CIDP patients will be compared to these of healthy controls wearing the smartwatch.

Patients were recruited in Düsseldorf and Münster.

Inclusion Criteria:

• IVIG treated ? (all criteria a-c must be met):

  1. Documented evidence of objective response to IVIG, with clinically meaningful improvement. Clinically meaningful improvement is defined as one of the following: ≥1-point decrease in adjusted INCAT score, ≥4 points increase in I-RODS total score, ≥3 points increase in MRC Sum score, ≥8 kilopascal improvement in mean grip strength (one hand), or an equivalent improvement based on information documented in medical records and per the PI's judgement.
  2. Must be on stable IVIG therapy, defined as no change greater than 10% in frequency or dose of immunoglobulin therapy or corticosteroids within 8 weeks prior to screening
  3. Evidence of clinically meaningful deterioration on interruption or dose reduction of IVIG therapy within 24 months prior to screening, determined by clinical examination or medical records. Clinically meaningful deterioration is defined as one of the following: ≥1-point increase in adjusted INCAT score, decrease in I-RODS total score ≥4 points, decrease in MRC Sum score ≥3, mean grip strength worsening of ≥8 kilopascals (one hand), or an equivalent deterioration based on information from medical records and at the PI's judgement.

Exclusion Criteria:

• unable to use smartwatch or/and smartphone device

CIDP patients with ongoing standard of care IVIG treatment, older or 18 years