Table 2: Characteristics of endometrial cancer cases and population-based controls who returned urine and saliva samples*.
Characteristic (N missing) |
Number (Percent) |
Cases (N = 480) |
Controls (N = 513) |
p-value† |
Demographics |
||||
Age at diagnosis |
||||
< 40 |
14 (1.4) |
12 (2.5) |
2 (0.4) |
< 0.0001 |
40-44 |
21 (2.1) |
15 (3.1) |
6 (1.2) |
|
45-49 |
37 (3.7) |
23 (4.8) |
14 (2.7) |
|
50-54 |
98 (9.9) |
59 (12.3) |
39 (7.6) |
|
55+ |
823 (82.9) |
371 (77.3) |
452 (88.1) |
|
Mean (SD) |
61.8 (8.6) |
60.5 (9.2) |
63.1 (7.9) |
< 0.0001 |
Education |
||||
High school or less |
371 (37.4) |
176 (36.7) |
195 (38.0) |
0.83 |
1-3 years of college |
261 (26.3) |
125 (26.0) |
136 (26.5) |
|
College or more |
361 (36.4) |
179 (37.3) |
182 (35.5) |
|
Employment |
||||
Not in labor force |
472 (47.5) |
217 (45.2) |
255 (49.7) |
0.16 |
Working |
521 (52.5) |
263 (54.8) |
258 (50.3) |
|
Family income, annual (62) |
||||
≤ $30.000 |
245 (26.3) |
138 (30.0) |
107 (22.7) |
0.006 |
$30.001 - $50.000 |
265 (28.5) |
140 (30.4) |
125 (26.5) |
|
$50.001 - $100.000 |
298 (32.0) |
130 (28.3) |
168 (35.7) |
|
> $100.000 |
52 (11.3) |
52 (11.3) |
71 (15.1) |
|
Marital status |
||||
Married/living with partner |
714 (71.9) |
318 (66.3) |
396 (77.2) |
< 0.0001 |
Divorced, separated, widowed |
220 (22.2) |
118 (24.6) |
102 (19.9) |
|
Never married |
59 (5.9) |
44 (9.2) |
15 (2.9) |
|
Race/ethnicity (4) |
||||
Hispanic |
6 (0.6) |
4 (0.8) |
2 (0.4) |
0.004 |
Non-Hispanic Black |
27 (2.7) |
21 (4.4) |
6 (1.2) |
|
Non-Hispanic White |
946 (95.6) |
452 (94.4) |
494 (96.9) |
|
Other Non-Hispanic |
10 (1.0) |
2 (0.4) |
8 (1.6) |
|
Work schedule (473) |
||||
Regular daytime shift |
439 (84.4) |
221 (84.4) |
218 (84.5) |
0.96 |
Other shift |
81 (15.6) |
41 (15.6) |
40 (15.5) |
|
Dietary habits |
||||
Days/week alcoholic beverages consumed (10) |
||||
0 |
440 (44.8) |
224 (47.1) |
216 (42.6) |
0.041 |
< 1 |
269 (27.4) |
139 (29.2) |
130 (25.6) |
|
1-2.9 |
125 (12.7) |
54 (11.3) |
71 (14.0) |
|
3 or more |
149 (15.2) |
59 (12.4) |
90 (17.8) |
|
Protein shake consumption (5) |
||||
None |
877 (88.8) |
414 (86.4) |
463 (91.0) |
0.0051 |
Less than 2 per week |
48 (4.9) |
22 (4.6) |
26 (5.1) |
|
2 per week or more |
63 (6.4) |
43 (9.0) |
20 (3.9) |
|
Whole milk consumption |
||||
5 or more times per week |
50 (5.0) |
32 (6.7) |
18 (3.5) |
0.023 |
Less than 5 times per week |
943 (95.0) |
448 (93.3) |
495 (96.5) |
|
Physical activity and weight |
||||
Body mass index, year before diagnosis (14) |
||||
Mean (SD) |
32.1 (9.2) |
35.3 (10.1) |
29.0 (6.9) |
< 0.0001 |
METs-minutes/week ^, total (1) |
||||
Mean (SD) |
36.4 (54.3) |
31.5 (48.8) |
41.0 (58.6) |
0.006 |
Any weight gain since age 25 (14) |
||||
Mean (SD) |
20.1 (18.0) |
24.1 (19.6) |
16.4 (15.6) |
< 0.0001 |
Smoking history |
||||
Smoke cigarettes (3) |
||||
Never |
652 (65.9) |
325 (68.0) |
327 (63.9) |
0.1 |
Former |
274 (27.7) |
130 (27.2) |
144 (28.1) |
|
Current |
64 (6.5) |
23 (4.8) |
41 (8.0) |
|
Smoking, total pack-years (6) |
||||
Mean for ever-smokers (SD) |
8.2 (17.8) |
6.3 (15.1) |
10.0 (19.9) |
0.001 |
Medical history |
||||
Breast cancer (2) |
||||
Yes |
50 (5.0) |
13 (2.7) |
37 (7.2) |
0.0012 |
No |
941 (95.0) |
466 (97.3) |
475 (92.8) |
|
Diabetes (3) |
||||
Yes |
183 (18.5) |
118 (24.7) |
65 (12.7) |
< 0.0001 |
No |
807 (81.5) |
360 (75.3) |
447 (87.3) |
|
Endometrial cancer in first degree relative (36) |
||||
Yes |
31 (3.2) |
25 (5.4) |
6 (1.2) |
0.0002 |
No |
926 (96.8) |
435 (94.6) |
491 (98.8) |
|
Endometriosis (20) |
||||
Yes |
164 (16.9) |
84 (18.0) |
80 (15.8) |
0.35 |
No |
809 (83.1) |
382 (82.0) |
427 (84.2) |
|
Hypertension (2) |
||||
Yes |
526 (53.1) |
275 (57.5) |
251 (48.9) |
0.007 |
No |
465 (46.9) |
203 (42.5) |
262 (51.1) |
|
Ovarian cancer (7) |
||||
Yes |
33 (3.4) |
30 (6.3) |
3 (0.6) |
< 0.0001 |
No |
953 (96.6) |
444 (93.7) |
509 (99.4) |
|
Medications and treatments |
||||
Birth control, years used (3) |
||||
Mean (SD)‡ |
6.0 (7.3) |
5.0 (6.2) |
7.0 (8.0) |
< 0.0001 |
Hormone replacement therapy, years used (14) |
||||
Mean (SD) |
3.3 (7.1) |
2.1 (5.9) |
4.4 (8.0) |
< 0.0001 |
Reproductive history |
||||
Age of menarche 11 or earlier (2) |
||||
Yes |
224 (22.6) |
123 (25.7) |
101 (19.7) |
0.025 |
No |
767 (77.4) |
356 (74.3) |
411 (80.3) |
|
Menopause status, year before diagnosis |
||||
Premenopausal |
149 (15.0) |
107 (22.3) |
42 (8.2) |
< 0.0001 |
Postmenopausal |
840 (84.6) |
372 (77.5) |
468 (91.2) |
|
Unknown |
4 (0.4) |
1 (0.2) |
3 (0.6) |
|
Nulliparous (4) |
148 (15.0) |
89 (18.6) |
59 (11.5) |
0.0018 |
*9 controls who reported a diagnosis of endometrial cancer were excluded. Variables refer to the year prior to diagnosis of endometrial cancer unless otherwise specified.
†P-value for chi-square test except for means, which were compared with a t-test.
‡Birth control refers to methods that release hormones, such as birth control pills, injections, patches, progesterone implants (Norplant), progestin-releasing intrauterine devices, or vaginal rings.
^METs minutes is a measure of the volume of activity which is computed by weighting each type of activity by its energy requirements defined in METs to yield a score in MET–minutes .