Table 1.
Baseline Characteristics according to Lung Function Categories: ARIC Study, 1987–1989
| Lung Function Category |
P Value | ||||
|---|---|---|---|---|---|
| Normal | Respiratory Symptoms with Normal Spirometric Results | Restrictive Impairment Pattern | COPD Pattern | ||
| n (%) | 6,108 (43) | 4,754 (34) | 832 (6) | 2,490 (18) | |
| Demographics | |||||
| Age, yr | 53.9 (5.7) | 53.9 (5.7) | 54.5 (5.6) | 55.1 (5.8) | <0.001 |
| Female, % | 57.1 | 56.0 | 52.4 | 50.5 | <0.001 |
| African American, % | 27.1 | 27.4 | 20.3 | 22.1 | <0.001 |
| Education level, % | <0.001 | ||||
| <High school | 17.9 | 26.0 | 31.3 | 29.5 | |
| High school graduate | 40.8 | 41.8 | 39.5 | 40.2 | |
| College/graduate school | 41.3 | 32.2 | 29.2 | 30.3 | |
| Behaviors | |||||
| Smoking status, % | <0.001 | ||||
| Current | 12.3 | 29.2 | 35.1 | 49.7 | |
| Former | 33.7 | 30.4 | 29.6 | 30.1 | |
| Never | 54.0 | 40.4 | 35.3 | 20.2 | |
| Pack-years* | 12.5 (6.5–30.0) | 18.1 (11.2–37.0) | 22.0 (16.0–43.0) | 28.9 (21.0–48.0) | <0.001 |
| Physical activity† | 2.5 (0.8) | 2.4 (0.8) | 2.3 (0.8) | 2.4 (0.8) | <0.001 |
| Respiratory indicators | |||||
| FEV1% predicted | 101.0 (12.1) | 97.2 (12.0) | 72.6 (8.3) | 74.8 (18.4) | <0.001 |
| FVC% predicted | 102.3 (11.7) | 99.2 (11.4) | 72.6 (7.3) | 94.1 (18.0) | <0.001 |
| FEV1/FVC % predicted | 98.2 (5.7) | 97.4 (5.6) | 99.5 (7.5) | 78.4 (9.5) | <0.001 |
| FEV1, L | 3.03 (0.71) | 2.91 (0.71) | 2.23 (0.54) | 2.31 (0.74) | <0.001 |
| FVC, L | 3.93 (0.95) | 3.81 (0.95) | 2.87 (0.72) | 3.74 (1.06) | <0.001 |
| FEV1/FVC | 77.3 (4.7) | 76.7 (4.7) | 78.0 (6.2) | 61.4 (7.8) | <0.001 |
| Self-reported symptoms, % | |||||
| Cough | 0.0 | 20.0 | 17.9 | 26.4 | <0.001 |
| Phlegm | 0.0 | 15.0 | 13.2 | 21.8 | <0.001 |
| Dyspnea | 0.0 | 13.2 | 16.0 | 14.1 | <0.001 |
| Self-reported medical diagnosis, % | |||||
| Bronchitis | 2.5 | 11.4 | 10.9 | 15.9 | <0.001 |
| Emphysema | 0.3 | 1.2 | 1.4 | 6.2 | <0.001 |
| Asthma | 2.1 | 7.1 | 4.9 | 13.3 | <0.001 |
| Other physiologic characteristics | |||||
| Body mass index, kg/m2 | 27.3 (4.8) | 28.5 (5.7) | 30.3 (6.5) | 26.0 (4.9) | <0.001 |
| Systolic blood pressure, mm Hg | 120.4 (17.8) | 121.2 (18.7) | 124.8 (20.1) | 120.7 (19.2) | <0.001 |
| Antihypertensive medications, % | 22.4 | 27.3 | 36.2 | 22.2 | <0.001 |
| Prevalent diabetes, % | 9.4 | 13.0 | 22.4 | 9.1 | <0.001 |
| HDL cholesterol, mg/dl | 53.3 (17.0) | 50.8 (16.6) | 46.1 (15.0) | 52.3 (17.7) | <0.001 |
| LDL cholesterol, mg/dl | 137.3 (38.7) | 139.1 (39.6) | 140.3 (40.0) | 134.5 (39.4) | <0.001 |
| Lipid-lowering medication, % | 2.7 | 2.7 | 4.9 | 2.5 | 0.002 |
| Prevalent CHD, % | 3.3 | 4.4 | 10.3 | 6.3 | <0.001 |
| Prevalent heart failure, % | 0.8 | 7.3 | 5.9 | 17.6 | <0.001 |
| Prevalent stroke, % | 3.2 | 5.9 | 8.1 | 4.7 | <0.001 |
| APOE, % | 0.27 | ||||
| ε4/ε4 | 2.7 | 2.6 | 3.5 | 2.3 | |
| ε2/ε4 or ε3/ε4 | 27.4 | 28.0 | 27.9 | 29.5 | |
| Other | 69.9 | 69.5 | 68.6 | 68.3 | |
| Weights | |||||
| Unstabilized weights (all) | 3.1 | 3.8 | 5.7 | 5.8 | |
| Unstabilized weights (visit 5) | 2.0 | 2.3 | 3.2 | 2.9 | |
| Stabilized weights (visit 5) | 0.9 | 1.0 | 1.2 | 1.1 | |
Definition of abbreviations: APOE = apolipoprotein E; ARIC = Atherosclerosis Risk in Communities; CHD = coronary heart disease; COPD = chronic obstructive pulmonary disease; HDL = high-density lipoprotein; LDL = low-density lipoprotein.
Data are shown as mean (SD) or percentage unless otherwise indicated.
*
Among ever-smokers. Data are shown as geometric mean (25th percentile–75th percentile).
†
Score on the sport index of the Baecke physical activity questionnaire (41).