title: Iron supplementation does not worsen respiratory health or alter the sputum microbiome in cystic fibrosis.
abstract: BACKGROUND
  Iron supplementation for hypoferremic anemia could potentiate bacterial growth in the cystic fibrosis (CF) lung, but clinical trials testing this hypothesis are lacking.
  
  
  METHODS
  Twenty-two adults with CF and hypoferremic anemia participated in a randomized, double-blind, placebo-controlled, crossover trial of ferrous sulfate 325mg daily for 6weeks. Iron-related hematologic parameters, anthropometric data, sputum iron, Akron Pulmonary Exacerbation Score (PES), and the sputum microbiome were serially assessed. Fixed-effect models were used to describe how ferrous sulfate affected these variables.
  
  
  RESULTS
  Ferrous sulfate increased serum iron by 22.3% and transferrin saturation (TSAT) by 26.8% from baseline (p<0.05) but did not affect hemoglobin, sputum iron, Akron PES, and the sputum microbiome.
  
  
  CONCLUSIONS
  Low-dose ferrous sulfate improved hypoferremia without correcting anemia after 6weeks. We did not observe significant effects on sputum iron, Akron PES, and the sputum microbiome. Although we did not identify untoward health effects of iron supplementation, a larger blinded randomized controlled trial would be needed to fully demonstrate safety.
authors: Pulmonary and Critical Care Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, United States. Electronic address: Alex.H.Gifford@hitchcock.org.
authors: Alex H
authors: AH
authors: Gifford
authors: Division of Pulmonary and Critical Care, Maine Medical Center, Portland, ME 04102, United States. Electronic address: ALEXAD1@mmc.org.
authors: Diana M
authors: DM
authors: Alexandru
authors: Biostatistics and Epidemiology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, United States. Electronic address: Zhigang.Li@dartmouth.edu.
authors: Zhigang
authors: Z
authors: Li
authors: Pulmonary and Critical Care Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, United States. Electronic address: Dana.B.Dorman@hitchcock.org.
authors: Dana B
authors: DB
authors: Dorman
authors: Pulmonary and Critical Care Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, United States. Electronic address: Lisa.A.Moulton@hitchcock.org.
authors: Lisa A
authors: LA
authors: Moulton
authors: Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, United States. Electronic address: Katherine.E.Price@dartmouth.edu.
authors: Katherine E
authors: KE
authors: Price
authors: Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, United States. Electronic address: Thomas.H.Hampton@dartmouth.edu.
authors: Thomas H
authors: TH
authors: Hampton
authors: Josephine Bay Paul Center for Comparative Molecular Biology and Evolution, Marine Biological Laboratory, Woods Hole, MA 02543, United States. Electronic address: sogin@mbl.edu.
authors: Mitchell L
authors: ML
authors: Sogin
authors: Division of Pulmonary and Critical Care, Maine Medical Center, Portland, ME 04102, United States. Electronic address: jzuckerman@cmamaine.com.
authors: Jonathan B
authors: JB
authors: Zuckerman
authors: Pulmonary and Critical Care Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, United States. Electronic address: H.Worth.Parker@hitchcock.org.
authors: H Worth
authors: HW
authors: Parker
authors: Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, United States. Electronic address: bas@dartmouth.edu.
authors: Bruce A
authors: BA
authors: Stanton
authors: Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, United States. Electronic address: georgeo@dartmouth.edu.
authors: George A
authors: GA
authors: O'Toole
mesh_terms: D000293:Adolescent; D000328:Adult; D018798:Anemia, Iron-Deficiency / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism; D018592:Cross-Over Studies; D003550:Cystic Fibrosis / Q000150:complications* / Q000378:metabolism; D004311:Double-Blind Method; D005260:Female; D005296:Ferrous Compounds / Q000008:administration & dosage* / Q000009:adverse effects*; D064451:Hepcidins / Q000378:metabolism; D006801:Humans; D008297:Male; D064307:Microbiota / Q000187:drug effects*; D008875:Middle Aged; D010919:Placebos; D013183:Sputum / Q000187:drug effects / Q000382:microbiology; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D005296:Ferrous Compounds; D064451:Hepcidins; D010919:Placebos; C545475:hepcidin 25, human; C020748:ferrous sulfate
keywords: Anemia; Cystic fibrosis; Hepcidin-25; Hypoferremia; Iron; Microbiome