Table 1. Baseline Characteristics by Lung Function Categorya.
| Characteristics | PRISm (n=4582)b | Obstructive spirometry (n=9440)b | Normal spirometry (n=39 679)b |
|---|---|---|---|
| Age, mean (SD), y | 54.9 (14.2) | 63.0 (12.0) | 50.7 (15.9) |
| Age group | |||
| <30 y | 349 (7.6) | 170 (1.8) | 6039 (15.2) |
| 30-39 y | 225 (4.9) | 116 (1.2) | 3152 (7.9) |
| 40-49 y | 797 (17.4) | 720 (7.6) | 7082 (17.9) |
| 50-59 y | 1428 (31.2) | 2453 (26.0) | 11 477 (28.9) |
| 60-69 y | 1024 (22.4) | 2875 (30.5) | 6815 (17.2) |
| 70-79 y | 654 (14.3) | 2418 (25.6) | 4239 (10.7) |
| ≥80 y | 105 (2.3) | 688 (7.3) | 875 (2.2) |
| Sex | |||
| Women | 2764 (60.3) | 4126 (43.7) | 23 398 (59.0) |
| Men | 1818 (39.7) | 5314 (56.3) | 16 281 (41.0) |
| Race and ethnicity | |||
| American Indian or Alaska Native | 208 (4.5) | 313 (3.3) | 1258 (3.2) |
| Black | 1115 (24.3) | 1558 (16.5) | 8999 (22.7) |
| East Asian or Pacific Islander | 40 (0.9) | 128 (1.4) | 491 (1.2) |
| Hispanic or Latino | 1515 (33.1) | 1017 (10.8) | 12 065 (30.4) |
| Non-Hispanic White | 1704 (37.2) | 6421 (68.0) | 16 854 (42.5) |
| Otherc | - | 3 (0.03) | 12 (0.03) |
| Educationd | |||
| <High school diploma | 777 (17.0) | 1442 (15.3) | 5637 (14.2) |
| Completed high school | 1250 (27.3) | 2571 (27.2) | 10 918 (27.5) |
| Some college | 702 (15.3) | 1331 (14.1) | 6510 (16.4) |
| ≥College | 1853 (40.4) | 4096 (43.4) | 16 614 (41.9) |
| Smoking statusd | |||
| Ever | 2491 (54.4) | 6959 (54.4) | 18 203 (45.9) |
| Currente | 1153 (46.3) | 2892 (41.6) | 6944 (38.1) |
| Pack-years among ever smokers, median (IQR) | 21.0 (7.0-38.0) | 31.8 (15.0-49.0) | 10.4 (3.0-26.0) |
| Body mass index, mean (SD)d,f | 30.8 (7.2) | 26.6 (5.0) | 28.2 (5.7) |
| FEV1% predicted, mean (SD) | 75.1 (9.4) | 80.6 (20.4) | 103.4 (13.4) |
| FVC% predicted, mean (SD) | 78.1 (11.4) | 100.3 (20.1) | 105.4 (14.4) |
| Preexisting comorbiditiesd | |||
| Hypertensiong | 2531 (55.2) | 5042 (53.4) | 14 955 (37.7) |
| Diabetesh | 1170 (25.5) | 1254 (13.3) | 5312 (13.4) |
| Chronic lower respiratory tract diseasei | 742 (16.2) | 1877 (19.9) | 3440 (8.7) |
| Asthmaj | 627 (13.7) | 1283 (13.6) | 2657 (6.7) |
| Heart failurek | 353 (7.7) | 881 (9.3) | 1899 (4.8) |
| Coronary heart diseasek | 393 (8.6) | 978 (10.4) | 1515 (3.8) |
| Strokek | 147 (3.2) | 282 (3.0) | 516 (1.3) |
| eGFRd,l | |||
| ≥60 | 3805 (83.0) | 7070 (74.9) | 33 794 (85.2) |
| 30-59 | 723 (15.8) | 2275 (24.1) | 5688 (14.3) |
| <30 | 54 (1.2) | 95 (1.0) | 197 (0.5) |
| Cohort | |||
| ARIC | 1031 (6.9) | 3375 (22.6) | 10 538 (70.5) |
| CARDIA | 196 (3.9) | 184 (3.7) | 4624 (92.4) |
| CHS | 404 (8.4) | 2004 (41.6) | 2406 (50) |
| FOC | 310 (8) | 840 (21.5) | 2748 (70.5) |
| HABC | 217 (8.4) | 659 (25.6) | 1702 (66.0) |
| HCHS/SOL | 1406 (10.3) | 868 (6.4) | 11 351 (83.3) |
| JHS | 374 (15) | 116 (4.6) | 2008 (80.4) |
| MESA | 436 (9.5) | 1089 (23.8) | 3060 (66.7) |
| SHS | 208 (11.9) | 305 (17.4) | 1242 (70.8) |
Abbreviations: ARIC, Atherosclerosis Risk in Communities study; CARDIA, Coronary Artery Risk Development in Young Adults study; CHS, Cardiovascular Health Study; eGFR, estimated glomerular filtration rate; FEV1, forced expiratory volume in the first second; FOC, Framingham Offspring Cohort; FVC, forced vital capacity; HABC, Health ABC study; HCHS/SOL, Hispanic Community Health Study/Study of Latinos; JHS, Jackson Heart Study; MESA, Multi-Ethnic Study of Atherosclerosis; PRISm, preserved ratio impaired spirometry; SHS, Strong Heart Study.
Values are reported as No. (%) unless otherwise indicated. All P values for comparisons between groups and P values for trend were <.001.
Lung function category definitions: PRISm (FEV1:FVC ratio ≥0.7 and FEV1 <80%), obstructive spirometry (FEV1:FVC ratio <0.7), and normal spirometry (FEV1:FVC ratio ≥0.7 and FEV1 ≥80%).
The race and ethnicity category of Other includes individuals who self-reported as other or as multiracial based on predetermined categories.
Multiple imputation was performed to address missingness. Values indicate averages over 10 imputed data sets.
Ever smokers is the denominator for deriving the percentage of current smokers.
Calculated as weight in kilograms divided by height in meters squared.
Indicates self-reported hypertension, systolic blood pressure of 140 mm Hg or greater, diastolic blood pressure of 90 mm Hg or greater, or use of antihypertensive medications.
Indicates self-reported diabetes, fasting blood glucose level of 126 mg/dL or greater, or use of oral hypoglycemic agents or insulin.
Indicates self-reported physician diagnosis of chronic obstructive pulmonary disease, chronic bronchitis, or emphysema.
Indicates self-reported physician diagnosis of asthma.
Indicates data on comorbidities at baseline, including self-reported coronary heart disease, congestive heart failure, and stroke. If missing, data was obtained from hospitalization records prior to baseline spirometry. In the JHS, self-reported information on heart failure and hospitalization records prior to baseline spirometry were not available. Hence, JHS participants with heart failure events occurring within 5 years of baseline spirometry were classified as having heart failure at baseline.
For baseline eGFR (measured as mL/min/1.73 m2), measurements obtained at baseline spirometry visit were used. If missing, first available eGFR measurements were used.