A multicenter, randomized, double-blinded trial of pyridostigmine in postpolio syndrome.
BACKGROUND
Postpoliomyelitis syndrome (PPS) is likely due to degeneration and dysfunction of terminal axons of enlarged postpolio motor units. Age-related decline in growth hormone and insulin-like growth factor (IGF-I) may be a contributing factor. Neuromuscular junction abnormalities and decreased IGF-I levels may respond to the anticholinesterase pyridostigmine, with consequent improvement in strength, fatigue, and quality of life.


OBJECTIVE
To determine the effect of pyridostigmine in PPS on health-related quality of life, isometric muscle strength, fatigue, and serum IGF-I levels; and to assess the safety of pyridostigmine in PPS.


METHODS
The study was a multicenter, randomized, double-blinded, placebo-controlled trial of a 6-month course of pyridostigmine 60 mg three times per day in 126 PPS patients. The primary data analysis compared mean changes of outcomes between treatment and control groups at 6 months using an intention to treat approach. Secondary analyses included a comparison of outcomes at 6 and 10 weeks, and in compliant patients.


RESULTS
The study showed no significant differences in pyridostigmine and placebo-treated patients with regard to changes in quality of life, isometric strength, fatigue, and IGF-I serum levels at 6 months in the primary analysis and in compliant patients. There were no differences in outcomes at 6 and 10 weeks between groups. However, very weak muscles (1 to 25% predicted normal at baseline) were somewhat stronger (p = 0.10, 95% CI of difference -9.5 to 73.3%), and in compliant patients IGF-I was somewhat increased (p = 0.15, 95% CI of difference -6.4 to 44.8 ng/mL) at 6 months with the medication. Pyridostigmine was generally well tolerated.


CONCLUSIONS
This study showed no significant differences between pyridostigmine and placebo-treated PPS patients on measures of quality of life, isometric strength, fatigue, and serum IGF-I.
Trojan
D A
DA
Department of Neurology, Montreal Neurological Institute and Hospital, Quebec, Canada.
Collet
J P
JP
Shapiro
S
S
Jubelt
B
B
Miller
R G
RG
Agre
J C
JC
Munsat
T L
TL
Hollander
D
D
Tandan
R
R
Granger
C
C
Robinson
A
A
Finch
L
L
Ducruet
T
T
Cashman
N R
NR
D000368:Aged; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016262:Postpoliomyelitis Syndrome / Q000188:drug therapy*; D011729:Pyridostigmine Bromide / Q000627:therapeutic use*
D011729:Pyridostigmine Bromide