Table 2

Odds ratios (95% CI) for iron deficiency predicting high A1C among adults aged ≥18 years, NHANES 1999–2006

Women*Men: A1C ≥5.5%
A1C ≥5.5%A1C ≥6.5%
n6,6666,6663,869
Unadjusted1.17 (0.95–1.43)0.82 (0.37–1.80)2.34 (1.26–4.33)
Adjusted for age, race/ethnicity1.47 (1.19–1.83)0.90 (0.42–1.94)2.03 (0.81–5.08)
Adjusted for age, race/ethnicity, waist circumference1.39 (1.11–1.73)0.79 (0.33–1.85)1.40 (0.69–2.87)
Adjusted for age, race/ethnicity, waist circumference, parity, hysterectomy1.33 (1.05–1.67)0.78 (0.32–1.90)NA
  • Data are odds ratios (95% CI). The referent group is adults who are iron-sufficient; an odds ratio >1 indicates that an iron-deficient adult has greater odds of having an elevated A1C than an iron-sufficient adult, and an odds ratio <1 indicates that an iron-deficient adult has a lower odds of having an elevated A1C than an iron-sufficient adult.

  • *316 female participants with iron deficiency had a measured A1C ≥5.5%; 32 female participants with iron deficiency had a measured A1C ≥6.5%.

  • †13 male participants with iron deficiency had a measured A1C ≥5.5%; 1 male participant with iron deficiency had a measured A1C ≥6.5%. NA, not applicable.