Table 2.
Characteristics of cases and controls in the main NCI-SEER non-Hodgkin lymphoma study and in analysis of residential proximity to dioxin-emitting facilities (number [percent], except where indicated)a
| |
NCI-SEER NHL study |
Study of residential proximity to dioxin-emitting facilitiesb |
||
|---|---|---|---|---|
| Cases (n = 1321) | Controls (n = 1057) | Cases (n = 969) | Controls (n = 749) | |
|
NHL Subtype |
|
|
|
|
| Diffuse large B-cell |
417 (32) |
|
304 (31) |
|
| Follicular |
318 (24) |
|
227 (23) |
|
| Chronic lymphocytic leukemia/small lymphocytic |
133 (10) |
|
102 (11) |
|
| Marginal zone |
106 (8) |
|
82 (8) |
|
| Other |
172 (13) |
|
128 (13) |
|
| NOS lymphoma |
175 (13) |
|
126 (13) |
|
| Age (years), median (IQR) |
58 (48–67) |
61 (50–68) |
61 (50–68) |
63 (53–69) |
|
Gender |
|
|
|
|
| Male |
711 (54) |
546 (52) |
509 (53) |
377 (50) |
| Female |
610 (46) |
511 (48) |
460 (47) |
372 (50) |
|
Race |
|
|
|
|
| Only White |
1123 (85) |
843 (80) |
844 (87) |
618 (83) |
| Any Black |
110 (8) |
151 (14) |
75 (8) |
99 (13) |
| Other/unknown |
86 (7) |
63 (6) |
50 (5) |
32 (4) |
|
Education level, years |
|
|
|
|
| <12 |
128 (10) |
111 (11) |
92 (9) |
81 (11) |
| 12-15 |
815 (62) |
616 (58) |
616 (64) |
444 (59) |
| 16+ |
377 (29) |
330 (31) |
261 (27) |
224 (30) |
|
Study Center |
|
|
|
|
| Detroit |
319 (24) |
214 (20) |
227 (23) |
161 (22) |
| Iowa |
361 (27) |
276 (26) |
282 (29) |
216 (29) |
| Los Angeles |
319 (24) |
273 (26) |
219 (23) |
172 (23) |
| Seattle |
322 (24) |
294 (28) |
241 (25) |
200 (27) |
|
Occupational exposure to dioxins |
|
|
|
|
| Ever worked in an industry with potential dioxin exposure |
27 (2.0) |
13 (1.2) |
20 (2.1) |
9 (1.2) |
|
Potential sources of non-industrial exposure to dioxins |
|
|
|
|
| Average population density (people per square mile), median (IQR) |
4281 (1503–7107) |
4233 (1339–7572) |
4261 (1369–7191) |
4129 (1277–7803) |
| Duration of living within 400m of a freight route, years; median, IQR |
0.5 (0–13) |
0 (0–13) |
4.5 (0–15) |
4.5 (0–15) |
|
Sources of dietary exposure to dioxinsc |
n = 464 |
n = 389 |
n = 316 |
n = 258 |
| Meat, g/day, median (IQR) |
140 (93–196) |
130 (89–182) |
133 (92–185) |
129 (84–181) |
| Fish, g/day, median (IQR) |
2.2 (0–6.5) |
2.8 (0–6.5) |
2.8 (0–6.5) |
2.8 (0–6.5) |
| Saturated fat, mg/day, median (IQR) | 24 (18–32) | 22 (15–31) | 23 (18–31) | 23 (15–32) |
IQR interquartile range.
aPercentages do not add to 100 due to missing data; 1 case in the main study was missing education information.
bParticipants with ≥70% of person-years 15 years before diagnosis/reference year with verified GPS and/or geocoded street address (including street intersections).
cDietary questionnaires were available for a subset of the population as indicated in the table.