Table 1.
Characteristics of the study participants
| A comparison of case and control subjects | ||||
|---|---|---|---|---|
| Variables | Cases (n = 385) | Controls (n = 536) | P | OR* (95% CI) |
| Age, mean (SD) | 60.6 (13.1) | 59.1 (12.5) | 0.065 | |
| Gender, n (%) | ||||
| Men | 131 (34.0) | 182 (34.0) | ||
| Women | 254 (66.0) | 354 (66.0) | 0.982 | |
| Ethnicity, n (%) | ||||
| White | 308 (80.0) | 404 (75.4) | ||
| Hispanic | 34 (8.8) | 47 (8.8) | ||
| African American | 40 (10.4) | 280 (14.9) | ||
| Others | 3 (0.8) | 5 (0.9) | 0.239 | |
| Cell storage time, mo† | 14.26 (6.5) | 12.42 (6.1) | 0.001 | |
| Blastogenic rate, %†,‡ | 24.55 (18.7) | 22.50 (16.2) | 0.190 | |
| Baseline CAT activity, scintillation counts/min† | 32,756 (20,258) | 33,096 (24,163) | 0.861 | |
| Registration year (1995–2006)† | ||||
| 1995 | 2 | 0 | ||
| 1996 | 8 | 15 | ||
| 1997 | 9 | 16 | ||
| 1998 | 15 | 9 | ||
| 1999 | 22 | 18 | ||
| 2000 | 33 | 20 | ||
| 2001 | 47 | 120 | ||
| 2002 | 47 | 70 | ||
| 2003 | 66 | 70 | ||
| 2004 | 57 | 56 | ||
| 2005 | 57 | 78 | ||
| 2006 | 22 | 64 | <0.001 | |
| DRC, mean (SD)† | 7.97 (2.57) | 8.70 (2.82) | 0.002 | 0.90 (0.84–0.96) |
| SHS exposure, n (%)§ | 217 (81.0) | 298 (69.6) | 0.001 | |
*
Adjusted by gender, ethnicity, and age.
†
Based on 219 cases and 309 controls.
‡
Percentage of cells that were stimulated by phytohemagglutinin.
§
Based on 268 cases and 428 controls.