Table 1.
Characteristics of women age 30 years and older from NHANES (1999-2008) with p-values for simple logistic regression analysis for associations between independent variables and breast cancer
| Cases (n=99) | Non-cases (n=3,120) | Total sample (n=3,219) | p-value | |
|---|---|---|---|---|
| UCd (μg/g) Geometric meana (std. dev.) | 0.46 (.05) | 0.39 (.01) | 0.39 (.01) | <0.001 |
| UCd (μg/g) Median | 0.45 | 0.39 | 0.39 | - |
| UCd Quartileb # (%): | <0.001 | |||
| Q1: UCd<0.22 (reference group) | 10 (10%) | 694 (22%) | 704 (22%) | |
| Q2: 0.22≤UCd<0.37 | 24 (24%) | 776 (25%) | 800 (25%) | |
| Q3: 0.37≤UCd<0.60 | 34 (34%) | 799 (26%) | 833 (26%) | |
| Q4: UCd≥0.60 | 31 (31%) | 851 (27%) | 882 (27%) | |
| Age (years) Mean (std. dev.) | 67 (13) | 54 (16) | 55 (16) | <0.001 |
| Age group # (%): | <0.001 | |||
| 30≤years<55 (reference group) | 21 (21%) | 1,671 (54%) | 1,692 (53%) | |
| 55≤years<69 | 31 (31%) | 733 (23%) | 764 (24%) | |
| 69 years and older | 47 (47%) | 716 (23%) | 763 (24%) | |
| Never-smokers # (%) | 55 (56%) | 1,885 (60 %) | 1,940 (60%) | 0.763 |
| Non-drinkers # (%) | 37 (37%) | 1,330 (43%) | 1,367 (42%) | 0.721 |
| Non-Hispanic white # (%) | 66 (67%) | 1,534 (49%) | 1,600 (50%) | <0.001 |
| Ever used hormonesc # (%) | 33 (36%) | 845 (29%) | 878 (30%) | 0.435 |
| Older than 26 years at 1st live birth or nulliparad # (%) | 26 (28%) | 619 (21%) | 645 (22%) | 0.465 |
| Menopausale,f # (%) | 84 (91%) | 1,717 (60%) | 1,801 (61%) | <0.001 |
Notes: Descriptive data unweighted; Simple logistic regression p-values generated using weighted data with statistical analysis for complex survey design
a Urine cadmium values imputed for observations with value of zero by assigning ½* minimum detected value
b UCd quartiles calculated based upon weighted creatinine adjusted cadmium frequencies for entire NHANES sample
c NHANES sample includes 91 cases and 2,879 non-cases
d NHANES sample includes 92 cases and 2,896 non-cases
e NHANES sample includes 92 cases and 2,884 non-cases
f Self-report of no period for 12 months in NHANES sample; excluded pregnant or lactating women from classification as menopausal.