Efficacy of oral iron in patients with restless legs syndrome and a low-normal ferritin: A randomized, double-blind, placebo-controlled study.
OBJECTIVE
Restless Legs Syndrome (RLS) is a primary disorder of sensation that affects sleep and has been associated with iron deficiency. The purpose of this study was to determine if symptomatic RLS patients with low-normal serum ferritin levels benefit from oral iron replacement.


METHODS
This was a randomized, placebo-controlled, double-blinded study. Eligible patients were randomized to oral iron therapy vs. appearance-matched placebo and followed over a 12 week period.


RESULTS
Baseline International Restless Leg Scale (IRLS) scores for the treatment (24.8+/-5.72) and placebo (23.0+/-5.03) groups were similar. Baseline ferritin levels for the treatment (40.6+/-15.3ng/ml) and placebo (36.7+/-20.8ng/ml) groups were also similar. After 12 weeks, IRLS scores decreased more in the treatment arm (10.3+/-7.40) than in the placebo arm (1.14+/-5.64), (p=0.01). Ferritin levels increased more in the treatment arm (25.1+/-20.3ng/ml) than in the placebo arm (7.5+/-13.7ng/ml), (p=0.04). We observed a nonsignificant trend toward improved quality of life in the treated patients, (p=0.07).


CONCLUSIONS
This is the first double-blinded, placebo-controlled study to demonstrate statistically significant improvement in RLS symptoms using oral iron therapy in patients with low-normal ferritin. The findings from this study suggest that additional larger randomized placebo-controlled trials of iron as treatment for patients with low-normal ferritin are warranted.
Wang
James
J
Department of Medicine, Madigan Army Medical Center, Tacoma, WA 98431-1100, United States.
O'Reilly
Brian
B
Venkataraman
Ramesh
R
Mysliwiec
Vincent
V
Mysliwiec
Angela
A
D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D005293:Ferritins / Q000097:blood*; D005296:Ferrous Compounds / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D012148:Restless Legs Syndrome / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy*; D016896:Treatment Outcome
D005296:Ferrous Compounds; C020748:ferrous sulfate; D005293:Ferritins