Table 4.
Multivariable Logistic Regression Models of Anemia Correlates in the REGARDS Renal Ancillary Study, United States, 2003–2007
| Unadjusted (n = 19,836) |
Model 1a (n = 19,826) |
Model 2b (n = 17,246) |
Model 3c (n = 16,886) |
Model 4d (n = 16,738) |
||||||
| OR | 95% CI | OR | 95% CI | OR | 95% CI | OR | 95% CI | OR | 95% CI | |
| Demographic variablese | ||||||||||
| Age (per 10 years) | 1.30 | 1.25, 1.35 | 1.41 | 1.36, 1.48 | 1.36 | 1.30, 1.43 | 1.30 | 1.24, 1.37 | 1.24 | 1.18, 1.31 |
| Female gender | 1.20 | 1.11, 1.31 | 1.09 | 1.00, 1.19 | 1.04 | 0.95, 1.14 | 1.06 | 0.96, 1.18 | 0.96 | 0.87, 1.07 |
| Black race | 3.31 | 3.05, 3.60 | 3.64 | 3.34, 3.97 | 3.27 | 2.97, 3.60 | 2.91 | 2.63, 3.22 | 2.78 | 2.50, 3.10 |
| Living in the stroke beltf vs. other region | 1.20 | 1.10, 1.30 | 1.37 | 1.26, 1.50 | 1.30 | 1.18, 1.43 | 1.25 | 1.13, 1.37 | 1.23 | 1.11, 1.36 |
| Socioeconomic variablese | ||||||||||
| Education less than high school | 2.03 | 1.82, 2.26 | 1.21 | 1.06, 1.38 | 1.12 | 0.98, 1.29 | 1.12 | 0.97, 1.29 | ||
| Annual income | ||||||||||
| <$25,000 | 2.57 | 2.28, 2.91 | 1.42 | 1.24, 1.63 | 1.24 | 1.07, 1.42 | 1.18 | 1.02, 1.37 | ||
| $25,000–$75,000 | 1.80 | 1.62, 2.01 | 1.29 | 1.15, 1.44 | 1.22 | 1.09, 1.38 | 1.18 | 1.04, 1.33 | ||
| >$75,000g | 1.00 | 1.00 | 1.00 | 1.00 | ||||||
| Medical conditionse | ||||||||||
| Vascular disease | 1.80 | 1.64, 1.96 | 1.45 | 1.30, 1.62 | 1.29 | 1.15, 1.45 | ||||
| Diabetes | 3.08 | 2.82, 3.35 | 2.18 | 1.96, 2.41 | 2.09 | 1.87, 2.33 | ||||
| Hypertension | 2.15 | 1.97, 2.35 | 1.32 | 1.19, 1.47 | 1.15 | 1.03, 1.28 | ||||
| Ever smoker | 0.83 | 0.77, 0.90 | 0.78 | 0.71, 0.86 | 0.76 | 0.69, 0.84 | ||||
| Body mass index (per 5 kg/m2) | 1.16 | 1.13, 1.20 | 1.00 | 0.99, 1.01 | 0.99 | 0.98, 1.00 | ||||
| Anemia-associated conditionse | ||||||||||
| Chronic kidney disease | 4.01 | 3.62, 4.43 | 3.55 | 3.13, 4.04 | ||||||
| Inflammation | 2.38 | 2.12, 2.66 | 1.75 | 1.52, 2.02 | ||||||
| Microcytosis | 7.28 | 6.34, 8.38 | 5.76 | 4.87, 6.80 | ||||||
Abbreviations: CI, confidence interval; OR, odds ratio; REGARDS, REasons for Geographic And Racial Differences in Stroke.
Model 1: age (per 10 years), female gender (yes/no), race (black vs. white), region (stroke belt vs. other).
Model 2: model 1 + education less than high school (yes/no), annual income (<$25,000, $25,000–$75,000, >$75,000).
Model 3: model 2 + vascular disease (yes/no), diabetes (yes/no), hypertension (yes/no), ever smoker (yes/no), body mass index (per 5 kg/m2).
Model 4: model 3 + chronic kidney disease (glomerular filtration rate <60 mL/minute per 1.73 m2), inflammation (C-reactive protein ≥10 mg/dL or leukocyte count ≥15 × 109/L), and microcytosis (mean corpuscular volume <80 fL).
Definitions are provided in the Materials and Methods section of the text.
North Carolina, South Carolina, Georgia, Tennessee, Alabama, Mississippi, Arkansas, Louisiana.
Reference category.