CIDP prognosis in patients with IVIG treatment‐related fluctuations

Abstract

Introduction/aims Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an acquired immune‐mediated peripheral nerve disorder with variable prognosis and long‐term dependence on immunotherapy. Frequent assessment of grip strength can be a useful tool to identify intravenous immunoglobulin (IVIG) treatment‐related fluctuations (TRFs) and optimize IVIG treatment in real‐time, but the long‐term implications of TRFs are unknown. We aimed to explore the impact that real‐time TRFs had on long‐term CIDP prognosis, strength impairment, and disability. Methods This retrospective observational cohort study analyzed standard of care clinical and treatment outcomes in patients who participated in a published prospective study of intra‐IVIG‐cycle grip strength quantification. Patients were analyzed based upon the presence or absence of TRFs, as determined in the initial prospective study. Results Data were available for 23 CIDP patients with a mean follow‐up period of 44.7 mo. There were no differences in baseline or follow‐up strength, disability, or IVIG usage in patients with a low number of fluctuations compared to those with a high number of fluctuations. In both groups, drug‐free remission was achieved in about one‐third of patients. Discussion TRFs are important to identify in order to optimize treatment in real time, but poorly predict long‐term disease activity status. The presence of minor TRFs are unlikely to result in substantial accumulation of disability over time. Periodic IVIG optimization trials using objective outcomes are encouraged in all CIDP patients receiving chronic IVIG treatment as a means to identify the lowest effective IVIG dose and frequency.

Serum neurofilament light chain does not detect self‐reported treatment‐related fluctuations in chronic inflammatory demyelinating polyneuropathy

“…One reason for the lack of correlation between INCAT‐ODSS and Z ‐Scores could be that the INCAT‐ODSS does not reflect active neuronal damage, but also reflects residual damage that does not result in elevated sNfL levels. This finding is in line with a recent study showing that TRFs measured by grip strength do not seem to lead to a higher long‐term disease burden [22]. This again indicates that TRFs have no pathological correlate in the sense of neuronal damage.…”

Introducing electronic monitoring of disease activity in patients with chronic inflammatory demyelinating polyneuropathy (EMDA CIDP): trial protocol of a proof of concept study

“…In addition, patients frequently report significant improvement shortly after the infusion, a phenomenon not yet explained from a pathophysiological standpoint. These gradual changes and fluctuations cannot be adequately reflected by current measurements, which only offer a ‘snapshot’ of the patient’s status at the time and place of examination [ 7 ]. Moreover, current outcome measures from prospective trials in IVIG treated patients do not allow meaningful conclusions for daily routine [ 1 ].…”