Table IV.

Serum iron of ALS patients.

Disease characteristic	Number of subjects	Serum iron, µmol/l	P-value
Limb-onset	16	13.39±4.91	0.0586
Bulbar-onset	8	18.08±6.40
Without dysphagia	7	14.39±4.30	0.7659
With dysphagia	17	15.18±6.38
Disease duration ≤12 months	10	16.40±8.34	0.3852
Disease duration >12 months	14	13.91±2.81
ALSFRS-R score <33	10	11.69±4.11	0.0155
ALSFRS-R score ≥33	14	17.28±5.76

ALS, amyotrophic lateral sclerosis; ALSFRS-R, Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised.