Vigorimeter grip strength in CIDP: a responsive tool that rapidly measures the effect of IVIG--the ICE study.
OBJECTIVE
In a recent trial in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), the ICE study, grip strength measurement captured significantly more improvement in patients receiving immune globulin (IGIV-C) intravenously than in those receiving placebo.


METHODS
We conducted a systematic analysis to determine the sensitivity of grip strength as an indicator of meaningful clinical changes in CIDP.


RESULTS
A randomized double-blind trial was undertaken in 117 CIDP patients who received IGIV-C or placebo every 3 weeks for up to 24 weeks. Grip strength and inflammatory neuropathy cause and treatment (INCAT) disability scores were assessed at each visit, and the responsiveness of each scale was compared. A minimum clinically important difference cut-off value for grip strength (>8 kPa) and INCAT score (>1 point) was applied to assess the proportion of responders to IGIV-C versus placebo. This analysis showed that grip strength demonstrated significant improvement earlier (as early as day 16) than the INCAT disability scale in patients receiving IGIV-C compared with placebo. A significantly higher proportion of improvers were seen in the IGIV-C group (37.5%-50.9%) than in the placebo group (21.1%-25.9%) for grip strength at day 16, week 3, week 6 and the end of the first period. Also, grip strength showed within the first 6 weeks in the placebo group significantly more patients with a clinically meaningful deterioration (>8 kPa), compared with the INCAT (>1-point deterioration) findings.


CONCLUSIONS
Grip strength can be considered a sensitive tool for assessing clinically relevant changes in patients with CIDP. Its use in daily practice is suggested.
Department of Neurology, Maastricht University Medical Centre, Maastricht, The Netherlands.
E K
EK
Vanhoutte
N
N
Latov
C
C
Deng
K
K
Hanna
R A C
RA
Hughes
V
V
Bril
M C
MC
Dalakas
P
P
Donofrio
P A
PA
van Doorn
H-P
HP
Hartung
I S J
IS
Merkies
D004185:Disability Evaluation; D004311:Double-Blind Method; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000627:therapeutic use*; D007155:Immunologic Factors / Q000627:therapeutic use*; D020277:Polyradiculoneuropathy, Chronic Inflammatory Demyelinating / Q000188:drug therapy* / Q000503:physiopathology*
D016756:Immunoglobulins, Intravenous; D007155:Immunologic Factors