Impairment measures versus inflammatory RODS in GBS and CIDP: a responsiveness comparison

Abstract

This study aimed to 'define responder' through the concept of minimum clinically important differences using the individually obtained standard errors (MCID-SE) and a heuristic 'external criterion' responsiveness method in patients with Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). One hundred and fourteen newly diagnosed or relapsing patients (GBS: 55, CIDP: 59) were serially examined (1-year follow-up). The inflammatory Rasch-built overall disability scale (I-RODS), Rasch-transformed MRC sum score (RT-MRC), and Rasch-transformed modified-INCAT-sensory scale (RT-mISS) were assessed. Being-a-responder was defined as having a MCID-SE cut-off ≥1.96. Also, the correlations between patients' scores on each scale and the EuroQoL health-status 'thermometer' (external criterion) were determined (higher correlation indicated better responsiveness). In both diseases, the SEs showed a characteristic 'U'-shaped dynamic pattern across each scales' continuum. The number of patients showing a meaningful change were higher for the I-RODS > RT-MRC > RT-mISS and were in GBS higher than CIDP patients. The MCID-SE concept using Rasch-transformed data demonstrated an individual pattern of 'being-a-responder' in patients with immune-mediated neuropathies, and the findings were validated by the external criterion responsiveness method. The I-RODS showed greater responsiveness compared with the MRC and INCAT-sensory scales, and its use is therefore recommended in future trials in GBS and CIDP.

Validation of the Serbian version of inflammatory Rasch‐built overall disability scale in patients with chronic inflammatory demyelinating polyradiculoneuropathy

“…22 I-RODS has been recently suggested as a primary outcome measure for clinical trials in CIDP patients. 6,23 Further research is needed to dem- responsiveness has been previously showed, 6,24…”

“…I‐RODS has been recently suggested as a primary outcome measure for clinical trials in CIDP patients . Further research is needed to demonstrate a responsiveness of the Serbian I‐RODS in order to fulfill the criterion of a satisfying outcome measure for clinical trials .…”

Correlation of the patient's reported outcome Inflammatory‐RODS with an objective metric in immune‐mediated neuropathies

“…In addition, the I-RODS is the only interval measure to assess general functionality in patients with GBS, CIDP and MGUSP and has fulfilled all modern Rasch-built scientific requirements [11,13,27]. Its superiority over generally applied often ordinal-based impairment and disability measures has recently been demonstrated, as well as showing some cross-cultural validity [13,28]. Through a consensus meeting with international experts in the field of inflammatory neuropathies and patients' representatives, it was concluded that the I-RODS and the vigorimeter are the most sensitive tools in these conditions [12].…”

Serum neurofilament light chain in chronic inflammatory demyelinating polyneuropathy

“…Non‐responders were defined as patients who showed deterioration or minimal or no improvement after 6 months of treatment. Improvement was defined as improvement by at least the minimal clinical important difference on the I‐RODS; and/or an increase of ≥8 kPa on grip strength …”

“…Improvement was defined as improvement by at least the minimal clinical important difference on the I-RODS; and/or an increase of ≥8 kPa on grip strength. 15 Relapse occurrence after treatment withdrawal in MT patients was defined as any deterioration that required restarting treatment, as judged by the treating physician. Non-responders and MT patients who relapsed after treatment withdrawal were defined as having active disease at follow-up.…”