Table 1.
Characteristics of the study sample: N = 2097 African American adults in the ARIC study
| Mean (SD) | Range | N | |
|---|---|---|---|
| Age (years) | 56.2 (5.7) | 47–70 | 2097 |
| BMI (kg/m2) | 30.1 (6.1) | 14.7–62.4 | 2096 |
| WC (cm) | 101.3 (15.1) | 61–163 | 2097 |
| BMI change (kg/m2) | 7.0 (6.0) | −25.9–36.4 | 2039 |
| Physical activity (scale of 1–5)a | 2.1 (0.6) | 1–4.25 | 2097 |
| WBC count (1000/mm3) | 5.6 (1.9) | 2.0–28.8 | 2097 |
| N (proportion) | |||
| Sex | |||
| Male | 763 (0.36) | 2097 | |
| Female | 1334 (0.64) | ||
| Field center | |||
| Forsyth County, NC | 157 (0.07) | 2097 | |
| Jackson, MS | 1940 (0.93) | ||
| BMI statusb | |||
| Underweight (BMI < 18.5 kg/m2) | 19 (0.01) | 2095 | |
| Normal weight (BMI 18.5–24.99 kg/m2) | 369 (0.18) | ||
| Overweight (BMI 25.0–29.99 kg/m2) | 789 (0.37) | ||
| Obese (≥30.0 kg/m2) | 918 (0.44) | ||
| WC statusb | |||
| Normal | 698 (0.33) | 2097 | |
| Elevated | 1399 (0.67) | ||
| Cigarette smoking | |||
| Current smoker | 512 (0.24) | 2097 | |
| Current nonsmoker | 1585 (0.76) | ||
| Alcohol use | |||
| Current drinker | 717 (0.34) | 2097 | |
| Current nondrinker | 1380 (0.66) | ||
| Education | |||
| <High school | 843 (0.40) | 2097 | |
| High school graduate | 581 (0.28) | ||
| >High school | 673 (0.32) | ||
| Household income | |||
| <$16 000 | 1087 (0.52) | 2097 | |
| $16 000–$24 999 | 379 (0.18) | ||
| $25 000–$34 999 | 278 (0.13) | ||
| $35 000–$49 999 | 202 (0.10) | ||
| >$50 000 | 151 (0.07) | ||
| Differential WBC proportionsc | |||
| Neutrophils | 0.56 | 2097 | |
| Lymphocytes | 0.36 | ||
| Monocytes | 0.05 | ||
| Eosinophils | 0.03 | ||
| Diabetes statusd | |||
| No | 1539 (0.74) | 2087 | |
| Yes | 548 (0.26) | ||
aSelf-reported leisure time physical activity using the Baecke Questionnaire at Visit 1.
bBMI status: underweight (BMI <18.5 kg/m2), normal weight (BMI 18.5–24.99 kg/m2), overweight (BMI 25.0–29.99 kg/m2) and obese (≥30.0 kg/m2). WC status: low risk (WC ≤88 cm for women and ≤102 cm for men) and high risk (WC >88 cm for women and >102 cm for men).
cDifferential WBC proportions were imputed using the method of Houseman et al. (32) using measured differentials from a subset of 179 ARIC subjects as the reference.
dPrevalent diabetes at the time of the DNA collection was defined as a self-reported physician diagnosis of or treatment for diabetes.