Table 1.
Characteristics of 273 Participants With and 296 Without Latent Mycobacterium tuberculosis Infection (LTBI)
| Characteristic | LTBI | No LTBI | P Value |
|---|---|---|---|
| Age, y, mean ± SD | 41.3 ± 15.9 | 41.0 ± 15.2 | .80 |
| Male sex | 153/273 | 153/296 | .30 |
| Ethnicity | <.001 | ||
| Asian | 113/273 | 82/296 | |
| Black | 58/273 | 45/296 | |
| Latino | 31/273 | 25/296 | |
| Pacific Islander | 35/273 | 21/296 | |
| White | 21/273 | 36/296 | |
| Other | 14/273 | 17/296 | |
| Foreign birth (n = 558) | 211/266 | 145/292 | <.001 |
| BCG vaccination (n = 563) | 165/270 | 118/293 | <.001 |
| BMI,a median | 25.0 | 25.8 | .17 |
| Homeless | 33/273 | 56/296 | .03 |
| Nocturnal exposure (n = 568) | 53/272 | 42/296 | .09 |
| Smoking (n = 562) | 63/272 | 70/290 | .79 |
| Alcohol use (n = 566) | 89/272 | 111/294 | .21 |
| Employed >20 h/wk | 121/273 | 137/296 | .61 |
| Highest education level (n = 559) | .04 | ||
| Less than grade school | 10/268 | 8/291 | |
| Grade school | 50/268 | 30/291 | |
| High school | 134/268 | 148/291 | |
| College | 55/268 | 77/291 | |
| >College | 19/268 | 28/291 | |
| Tuberculosis history in first-degree relative | 61/273 | 48/296 | .06 |
| Index characteristic | |||
| Bilateral disease detected by chest radiography (n = 461) | 120/237 | 78/224 | .001 |
| Cavitation(s) detected by chest radiography (n = 466) | 146/240 | 110/226 | .008 |
| AFB smear finding | <.001 | ||
| Negative | 11/236 | 36/232 | |
| 1+ or 2+ | 53/236 | 67/232 | |
| 3+ or 4+ | 172/236 | 129/232 | |
| LTBI diagnosis, participants, no. | |||
| TST (n = 256) | 105 | 151 | |
| IGRA (n = 358) | 171 | 187 | |
| Dual testing (n = 86) | 49 | 36 | |
Data are percentage of participants, unless otherwise indicated.
Abbreviations: AFB, acid-fast bacilli; IGRA, interferon γ release assay; TST, tuberculin skin test.
a Body mass index (BMI) is calculated as the weight in kilograms divided by the height in meters squared.