Table 1.
Characteristics of 5032 MESA Participants by SHS Exposure, 2000–2002
| Overall | Unexposed | 1 h/wk | 2–3 h/wk | 4–11 h/wk | ≥12 h/wk | P Value | |
|---|---|---|---|---|---|---|---|
| No. | 5032 | 3035 | 682 | 428 | 480 | 407 | |
| Sociodemographic factors | |||||||
| Men | 46.0 | 44.1 | 50.0 | 47.4 | 53.3 | 43.2 | <0.001 |
| Age, y | 62.5 (10.3) | 63.9 (10.4) | 59.8 (9.8) | 61.1 (10) | 60.5 (9.6) | 60.5 (9.3) | <0.001 |
| Race/ethnicity | <0.001 | ||||||
| White | 39.5 | 35.3 | 50.6 | 43.7 | 44.2 | 41.5 | |
| Black | 24.1 | 21.0 | 24.1 | 29.4 | 31.0 | 33.7 | |
| Chinese American | 14.1 | 17.9 | 10.0 | 10.1 | 7.3 | 5.2 | |
| Hispanic | 22.4 | 25.9 | 15.4 | 16.8 | 17.5 | 19.7 | |
| Education | <0.001 | ||||||
| High school or less | 35.0 | 38.1 | 22.0 | 30.4 | 33.8 | 39.8 | |
| Some college but no degree/technical school certificate | 22.1 | 19.8 | 23.0 | 25.7 | 28.1 | 26.3 | |
| Associate's degree, bachelor's degree, or graduate school | 43.0 | 42.1 | 55.0 | 43.9 | 38.1 | 33.9 | |
| Less than $25 000/y | 31.3 | 36.8 | 18.5 | 22.4 | 26.3 | 27.3 | <0.001 |
| CVD risk factors | |||||||
| Family history of CHD | 41.2 | 39.7 | 43.5 | 44.3 | 44.9 | 42.2 | 0.14 |
| Current alcohol usea | 68.4 | 65.1 | 74.0 | 74.7 | 69.0 | 72.5 | <0.001 |
| Former smokers | 40.9 | 37.4 | 45.9 | 44.2 | 49.0 | 46.4 | <0.001 |
| BMI, kg/m2 | 28.2 (5.4) | 27.7 (5.4) | 28.2 (5.2) | 28.5 (5.3) | 29.1 (5.6) | 30.0 (5.7) | <0.001 |
| Physical activity (MET, h/wk) | 94.6 (97.9) | 82.1 (80.3) | 100.9 (102.8) | 113.4 (131.3) | 130.6 (130.6) | 115.3 (104.3) | <0.001 |
| Hypertension | 44.5 | 45.5 | 39.0 | 43.2 | 43.3 | 48.4 | 0.01 |
| Hypertension medication | 36.9 | 37.8 | 32.3 | 34.8 | 36.9 | 40.3 | 0.04 |
| Systolic blood pressure, mm Hg | 126.4 (21.4) | 127.1 (21.9) | 123.8 (20.1) | 126.1 (20.9) | 124.5 (19.8) | 128.0 (21.5) | <0.001 |
| Diabetes mellitus | 11.8 | 12.3 | 7.6 | 14.0 | 11.7 | 13.3 | 0.005 |
| Fasting glucose, mg/dL | 96.7 (29.1) | 97 (29.5) | 93.3 (21.8) | 96 (27) | 98.2 (33.6) | 98.9 (32) | 0.01 |
| Lipid‐lowering medications | 16.6 | 17.3 | 13.9 | 18.2 | 15.8 | 14.5 | 0.14 |
| Total cholesterol, mg/dL | 194.3 (34.6) | 193.6 (34.2) | 196.2 (35) | 193.2 (34.9) | 195 (36.8) | 196.2 (33.8) | 0.47 |
| LDL‐C, mg/dL | 117.6 (31.3) | 116.9 (30.8) | 119.1 (32.1) | 118 (32.2) | 118.4 (32.7) | 118.3 (30.7) | 0.47 |
| Urinary cotinine,a ng/mL | 10.9 (14.6) | 8.8 (9.7) | 11.2 (16.5) | 9.8 (7.8) | 15.4 (20.8) | 22.4 (27.2) | <0.001 |
| Detectable urinary cotininea | 10.0 | 4.6 | 10.5 | 9.4 | 22.2 | 36.9 | <0.001 |
| Living with a smoker as a childa | 52.6 | 49.2 | 60.3 | 60.4 | 54.5 | 55.7 | <0.001 |
| Living with a smoker as an adulta | 40.0 | 35.4 | 41.7 | 44.9 | 48.0 | 57.6 | <0.001 |
| Inflammation markers | |||||||
| hsCRP, mg/L | 1.8 (0.8–4.0) | 1.6 (0.7–3.8) | 1.8 (0.8–3.8) | 1.8 (0.8–4.5) | 1.9 (0.8–4.2) | 2.4 (1.1–5.0) | 0.04 |
| hsCRP ≥2, mg/L | 45.7 | 43.5 | 45.3 | 48.1 | 48.1 | 57.0 | <0.001 |
| IL‐6, pg/mL | 1.5 (1.2) | 1.5 (1.2) | 1.4 (1) | 1.5 (1.1) | 1.4 (1.1) | 1.6 (1.2) | 0.01 |
| Fibrinogen, mg/dL | 343.9 (72.1) | 346.5 (72.3) | 339.5 (70.5) | 338.2 (76.5) | 335.4 (69.2) | 347.9 (71) | <0.001 |
| Subclincal atherosclerosis markers | |||||||
| Internal cIMT, mm | 1.05 (0.59) | 1.05 (0.59) | 1.00 (0.54) | 1.05 (0.60) | 1.05 (0.57) | 1.10 (0.67) | 0.19 |
| Common cIMT, mm | 0.87 (0.19) | 0.87 (0.20) | 0.85 (0.18) | 0.87 (0.19) | 0.86 (0.19) | 0.88 (0.18) | 0.03 |
| CAC >0 | 49.2 | 51.6 | 41.9 | 47.9 | 48.3 | 45.7 | <0.001 |
| CAC ≥75th percentile | 25.0 | 26.8 | 20.1 | 21.3 | 24.6 | 24.6 | 0.002 |
| PAD markers | |||||||
| ABI ≤0.9 | 2.9 | 3.1 | 1.9 | 3.5 | 2.1 | 3.4 | 0.31 |
| ABI ≥1.4 | 0.6 | 0.6 | 0.3 | 0.7 | 1.3 | 1.0 | 0.27 |
| ABI ≤0.9 or ABI ≥1.4 | 3.52 | 3.62 | 2.20 | 4.21 | 3.33 | 4.42 | 0.27 |
Values are expressed as mean (SD), percentage, or median (interquartile range). P values are the differences between groups using 1‐way ANOVA or chi‐square as appropriate. ABI indicates ankle‐brachial index; BMI, body mass index; CAC, coronary artery calcification; CHD, coronary heart disease; CVD, cardiovascular disease; cIMT, carotid intima‐media thickness; hsCRP, high‐sensitivity C‐reactive protein; IL‐6, interleukin 6; LDL‐C, low‐density lipoprotein cholesterol; MESA, Multi‐Ethnic Study of Atherosclerosis; MET, metabolic equivalent; PAD, peripheral arterial disease; SHS, secondhand smoke.
All values are for the entire study sample except for current alcohol use (n=3962), urinary cotinine concentration (n=2983), living with a smoker as a child (n=2977), and living with a smoker as an adult (n=2979).