title: Relationship of Iron Deficiency and Serum Ferritin Levels with Pulmonary Hypertension: The Jackson Heart Study.
abstract: OBJECTIVE
  Iron deficiency is prevalent in idiopathic pulmonary arterial hypertension (IPAH), but whether iron deficiency or ferritin levels are associated with pulmonary hypertension (PH) in the general population is unknown.
  
  
  METHODS
  We performed a cross-sectional analysis of data on iron deficiency (exposure), and PH (pulmonary artery systolic pressure>40mmHg on echocardiogram) (outcome) on subjects with complete data on exposures and outcomes as well as covariates (n = 2,800) enrolled in the Jackson Heart Study, a longitudinal prospective observational cohort study of heart disease in African-Americans from Jackson, Mississippi. Iron deficiency was defined as a serum ferritin level < 15ng/mL (females); < 30ng/mL (males). We determined crude prevalence ratios (PRs) for PH in iron deficient versus non-iron deficient groups using modified Poisson regression modeling. We also analyzed the prevalence of PH by sex-specific quartiles of ferritin (Females ≤ 47ng/mL; > 47ng/mL- 95ng/mL; > 95ng/mL- 171ng/mL; > 171ng/mL; Males ≤ 110ng/mL; > 110ng/mL- 182ng/mL; > 182ng/mL- 294ng/mL; > 294ng/mL), using the same modeling technique with the lowest quartile as the referent.
  
  
  RESULTS
  Median pulmonary artery systolic pressure was 27mmHg (interquartile range 23-31mmHg) in the study cohort. 147 subjects (5.2%) had PH and 140 (5.0%) had iron deficiency. However, of the 147 subjects with PH, only 4 were also iron deficient. The crude PH PR was 0.5 (95% CI 0.2-1.4) in iron-deficiency compared to non-deficient. In analysis by quartiles of ferritin, adjusting for age and sex, there was no evidence of association with PH in quartiles 2 (PR 1.1, 95% CI 0.7-1.6), 3 (PR 0.8, 95% CI 0.5-1.3), or 4 (PR 0.8, 95% CI 0.5-1.2) compared with quartile 1 (referent group, PR 1). Further analyses of the relationship between PH and ferritin as a log-transformed continuous variable or by quartiles of serum iron showed similar results.
  
  
  CONCLUSIONS
  In the Jackson Heart Study, the prevalence of PH was similar in iron-deficient and non-iron deficient subjects. There was no evidence of association between ferritin (or serum iron) levels and PH.
  
  
  CONCLUSIONS
  Iron deficiency has been associated with IPAH, a rare disorder. However, in a large community-based sample of African-Americans, there was no evidence that iron deficiency or low iron levels were associated with PH.
authors.affiliation: Vascular Research Laboratory, Providence VA Medical Center, Providence, RI, United States of America.|Department of Medicine, Alpert Medical School of Brown University, Providence, RI, United States of America.
authors.forename: Matthew
authors.identifier: http://orcid.org/0000-0002-5955-0571
authors.initials: M
authors.lastname: Jankowich
authors.affiliation: Center for Public Health and Clinical Epidemiology, Brown University, Providence, RI, United States of America.
authors.forename: Beth
authors.initials: B
authors.lastname: Elston
authors.affiliation: Department of Medicine, Alpert Medical School of Brown University, Providence, RI, United States of America.
authors.forename: Samuel K
authors.initials: SK
authors.lastname: Evans
authors.affiliation: Vascular Research Laboratory, Providence VA Medical Center, Providence, RI, United States of America.|Department of Medicine, Alpert Medical School of Brown University, Providence, RI, United States of America.
authors.forename: Wen-Chih
authors.initials: WC
authors.lastname: Wu
authors.affiliation: Vascular Research Laboratory, Providence VA Medical Center, Providence, RI, United States of America.|Department of Medicine, Alpert Medical School of Brown University, Providence, RI, United States of America.
authors.forename: Gaurav
authors.initials: G
authors.lastname: Choudhary
mesh_terms: D000328:Adult; D001741:Black or African American; D000368:Aged; D003430:Cross-Sectional Studies; D065627:Familial Primary Pulmonary Hypertension / Q000150:complications* / Q000208:ethnology; D005260:Female; D005293:Ferritins / Q000097:blood*; D006801:Humans; D000090463:Iron Deficiencies; D019189:Iron Metabolism Disorders / Q000150:complications* / Q000208:ethnology; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D008922:Mississippi; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D005293:Ferritins