title: Restless legs syndrome, pica, and iron status in blood donors.
abstract: BACKGROUND
  The association of blood donation-related iron deficiency with pica or restless legs syndrome (RLS) remains poorly elucidated. This study evaluated the prevalence of RLS and pica in blood donors completing the REDS-II Iron Status Evaluation (RISE) study.
  
  
  METHODS
  RISE enrolled 2425 blood donors in a prospective cohort study; 1334 donors provided blood samples to characterize iron status and answered a questionnaire inquiring into symptoms of RLS and pica at a final visit after 15 to 24 months of follow-up. Associations between both conditions and iron status were evaluated.
  
  
  RESULTS
  There were 9 and 20% of donors reporting symptoms of probable or probable/possible RLS, respectively. Iron depletion and donation intensity were not predictive of RLS. Pica was reported by 65 donors (5.5%), half of whom reported daily cravings. Prevalence of pica increased with degree of iron depletion in women (2% in iron-replete females, 13% in those with ferritin < 12 ng/mL), but not in men. Probable RLS and pica coexpressed in eight individuals, but no more frequently than expected by chance.
  
  
  CONCLUSIONS
  RLS and pica have been associated with iron deficiency in nondonor populations. This study indicates a potentially high prevalence of RLS in frequent blood donors but shows no association with iron status or donation intensity. Low iron stores were associated with higher prevalence of pica, but only in females. Furthermore, the results are incompatible with RLS and pica sharing a common pathophysiology.
authors.affiliation: American Red Cross Blood Services, New England Region, Dedham, Massachusetts 02026, USA. Bryan.Spencer@redcross.or
authors.forename: Bryan R
authors.initials: BR
authors.lastname: Spencer
authors.forename: Steven
authors.initials: S
authors.lastname: Kleinman
authors.forename: David J
authors.initials: DJ
authors.lastname: Wright
authors.forename: Simone A
authors.initials: SA
authors.lastname: Glynn
authors.forename: David B
authors.initials: DB
authors.lastname: Rye
authors.forename: Joseph E
authors.initials: JE
authors.lastname: Kiss
authors.forename: Alan E
authors.initials: AE
authors.lastname: Mast
authors.forename: Ritchard G
authors.initials: RG
authors.lastname: Cable
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018798:Anemia, Iron-Deficiency / Q000150:complications* / Q000175:diagnosis; D001782:Blood Donors; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010842:Pica / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D015995:Prevalence; D011446:Prospective Studies; D012148:Restless Legs Syndrome / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D012307:Risk Factors; D057566:Self Report