Related Experiment Video
Updated: Nov 17, 2025
Automated Gait Analysis in Mice with Chronic Constriction Injury
Published on: October 17, 2017
Quantifying Treatment-Related Fluctuations in CIDP: Results of the GRIPPER Study
Jeffrey A Allen1, Mamatha Pasnoor2, Mazen M Dimachkie2
1From the Department of Neurology (J.A.A.), and School of Public Heath (M.B.F.), Division of Biostatistics, University of Minnesota, Minneapolis; Department of Neurology (M.P., M.M.D.), University of Kansas Medical Center, Kansas City; Department of Neurology (S.A.-D.), Northwestern University, Chicago, IL; Department of Neurology (T.H.B.), Columbia University Medical Center, New York, NY; Neurology at Johns Creek (A.A.C.), LLC, Atlanta, GA; BriovaRx (T.W.), Lenexa, KS; Department of Neurology (J.T.K.), Ohio State University, Columbus; Department of Neurology (I.M.), Maastricht University Medical Centre+; Curaçao Medical Center (I.M.), Willemstad, the Netherlands; Department of Neurology (K.C.G.), St. Elizabeth's Medical Center, Tufts University School of Medicine, Boston, MA; and Department of Neurology (R.A.L.), Cedars-Sinai Medical Center, Los Angeles, CA. jaallen@umn.edu.
Objective:
The objective of this study was to explore the extent of IV immunoglobulin (IVIG) treatment-related fluctuations (TRFs) by using home collection of daily grip strength in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and to use that information to develop evidence-based treatment optimization strategies.
Methods:
This prospective observational study included 25 patients with well-defined CIDP. Participants recorded grip strength daily for 6 months. Disability and gait metrics were collected weekly. Serum immunoglobulin G levels were obtained at peak, trough, and midcycle IVIG intervals. Day-to-day grip strength changes <10% were considered random. To identify patients with TRFs, 3-day averaged grip strength was calculated on each consecutive day after an IVIG infusion. TRFs were defined as ≥10% 3-day averaged grip strength difference compared to the pre-IVIG baseline.
Results:
Participants successfully recorded grip strength on all but 9% of recordable days. Twelve patients (48%) were classified as low/no fluctuaters and 13 (52%) as frequent fluctuaters. In the frequent fluctuating group, grip strength improved over 1 week and thereafter was relatively stable until the third week after infusion. Grip strength was significantly correlated with measures of disability.
Conclusions:
Grip strength collection by patients at home is reliable, valid, and feasible. A change in grip strength by ≥10% is a useful, practical, and evidence-based approach that may be used to identify clinically meaningful TRFs. From these data, we propose a treatment optimization strategy for patients with CIDP on chronic IVIG that may be applied to routine clinic care during both face-to-face and virtual video or telephone patient encounters.
Trial Registration Information:
ClinicalTrials.gov Identifier: NCT02414490.
