Meta-analysis of the relationship between amyotrophic lateral sclerosis and susceptibility to serum ferritin level elevation

OBJECTIVE To study the possible relationship between amyotrophic lateral sclerosis (ALS) patients and their susceptibility to serum ferritin level elevation. METHODS We searched the PubMed, Springer, Medline, and OVID databases for any-language original research articles relating to serum ferritin levels in ALS patients published between June 2005 and June 2015. The search term used with `amyotrophic lateral sclerosis`, `ferritins`, `ferritin`, `iron`, `iron stores, `iron status, `iron intake`, and `iron consumption`. The meta-analysis software RevMan 5.0 was used for the heterogeneity test, and to test for the overall effect. RESULTS Six case-control studies met our inclusion criteria including data from a total of 1813 participants. The mean difference of serum ferritin levels comparing ALS to healthy controls was 69.05 (95% confidence interval: 52.56-85.54; p<0.00001); heterogeneity: p=0.03; I2=50%. The findings indicate homology in the sensitivity analysis. Funnel plot assessment indicated publication bias. CONCLUSION Our results suggest that ALS is positively associated with susceptibility to the elevation of serum ferritin levels; however, further evidence is required to support this.