Table 2.
Baseline Characteristics for Women Enrolled in the WHIOS Cohort and for Women Selected in the Nested Case-Control Study of Type 2 Diabetesa
| Variable | WHIOS Cohortb (N=80 509) | Cases (n=1584) | Controls (n=2198) | P Valuec |
|---|---|---|---|---|
| Age, mean (SD), y | 63.3 (7.3) | 62.7 (7.0) | 62.3 (7.0) | |
| Age, No. (%), y | ||||
| <60 | 26 885 (33.4) | 549 (34.7) | 822 (37.4) | |
| 60–69 | 35 304 (43.9) | 715 (45.1) | 972 (44.2) | |
| ≥70 | 18 320 (22.8) | 320 (20.2) | 404 (18.4) | |
| BMI, mean (SD) | 26.9 (5.6) | 32.3 (7.0) | 27.6 (5.9) | <.001 |
| Body weight, mean (SD), kg | 70.8 (16.3) | 84.3 (20.2) | 72.2 (17.5) | <.001 |
| Waist, mean (SD), cm | 83.1 (2.0) | 97.0 (15.2) | 83.3 (2.0) | <.001 |
| Waist to hip ratio, mean (SD) | 0.8 (0.1) | 0.9 (0.1) | 0.8 (0.1) | <.001 |
| Race/ethnicity, No. (%) | ||||
| White | 69 367 (86.2) | 968 (61.1) | 968 (44.0) | |
| Black | 5736 (7.1) | 366 (23.1) | 732 (33.3) | |
| Hispanic/Latina | 3035 (3.8) | 152 (9.6) | 303 (13.8) | |
| Asian/Pacific Islander | 2371 (2.9) | 98 (6.2) | 195 (8.9) | |
| Hypertension, No. (%) | 23 115 (28.7) | 788 (49.7) | 706 (32.1) | <.001 |
| Treated high cholesterol levels, No. (%) | 9872 (12.3) | 294 (18.6) | 262 (11.9) | <.001 |
| Physical activity, mean (SD), METS/wk | 14.1 (14.5) | 9.8 (12.4) | 12.8 (14.4) | <.001 |
| Alcohol consumption, No. (%) | ||||
| Nondrinkerd | 8394 (10.4) | 271 (17.1) | 352 (16.0) | |
| Past drinker | 13 384 (16.6) | 427 (27.0) | 470 (21.4) | .32 |
| <1 Drink/mo | 9219 (11.5) | 249 (15.7) | 286 (13.0) | .74 |
| <1 Drink/wk | 16 474 (20.5) | 325 (20.5) | 444 (20.2) | .02 |
| 1–6 Drinks/wk | 21 741 (27.0) | 221 (14.0) | 449 (20.4) | <.001 |
| ≥7 Drinks/wk | 10 761 (13.4) | 76 (4.8) | 182 (8.3) | <.001 |
| Cigarette smoking, No. (%) | ||||
| Neverd | 40 686 (50.5) | 786 (49.6) | 1211 (55.1) | |
| Past | 33 912 (42.1) | 657 (41.5) | 811 (36.9) | .05 |
| Current | 4828 (6.0) | 121 (7.6) | 148 (6.7) | .02 |
| Family history of diabetes, No. (%) | 23 625 (29.3) | 849 (53.6) | 777 (35.4) | <.001 |
| WBC count, median (IQR), ×1000/mL | 5.6 (4.7–6.6) | 6.3 (5.3–7.7) | 5.4 (4.5–6.5) | <.001 |
| Fasting glucose level, mg/dL | 122 (106–147) | 92 (87–98) | <.001 | |
| Impaired fasting glucose level, No. (%) | ||||
| ≥110 mg/dL | 1112 (70.2) | 139 (6.3) | <.001 | |
| ≥100 mg/dL | 1329 (83.9) | 448 (20.4) | <.001 | |
| Fasting insulin level, median (IQR), μIU/mL | 12.6 (8.1–18.6) | 6.4 (4.4–9.6) | <.001 | |
| HOMA-IR, median (IQR) | 4.0 (2.5–6.3) | 1.4 (1.0–2.3) | <.001 | |
| HOMA-B, median (IQR) | 75.1 (44.6–118.1) | 81.7 (56.1–120.2) | .06 | |
| TNF-R2 level, median (IQR), pg/mL | 2632.7 (2190.6–3296.6) | 2361.4 (1927.5–2883.6) | <.001 | |
| IL-6 level, median (IQR), pg/mL | 2.6 (1.6–4.6) | 1.5 (1.0–2.8) | <.001 | |
| hsCRP level, median (IQR), mg/L | 4.0 (2.0–7.6) | 2.1 (0.8–4.4) | <.001 | |
| E-selectin level, median (IQR), ng/mL | 49.3 (33.6–71.0) | 36.9 (26.0–50.9) | <.001 | |
| ICAM-1 level, median (IQR), ng/mL | 323.6 (268.2–383.9) | 280.4 (234.0–330.4) | <.001 | |
| VCAM-1 level, median (IQR), ng/mL | 765.2 (595.2–972.1) | 696.3 (543.0–861.8) | <.001 | |
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); HOMA-B, homeostasis model assessment of beta cell function; HOMA-IR, homeostasis model assessment of insulin resistance; IQR, interquartile range; METS, metabolic equivalents; WBC, white blood cell; WHIOS, Women’s Health Initiative Observational Study. Other abbreviations: See Table 1.
SI conversion factors: To convert glucose to millimoles per liter, multiply by 0.0555; hsCRP to nanomoles per liter, multiply by 9.524; insulin to picomoles per liter, multiply by 6.945; and WBC to 109 per liter, multiply by 0.001.
Numbers might not total all women in the WHIOS cohort/cases/controls because of missing values. Percentages have been rounded and might not total 100 because of missing values.
Excludes those with a history of cardiovascular disease or diabetes at baseline, Native American subjects, and those with unknown race/ethnicity. Biomarkers were not measured (except WBC) for women in the WHIOS cohort except those in the nested case-control study. Hence, the values were left blank for the biomarkers.
P value from comparing cases and controls in the nested case-control study. P value is not presented for the matching factors.
Indicates reference category.