Cigarette Smoking, Physical Activity, and Alcohol Consumption as Predictors of Cancer Incidence among Women at High Risk of Breast Cancer in the NSABP P-1 Trial

Stephanie R. Land; Qing Liu; D. Lawrence Wickerham; Joseph P. Costantino; Patricia A. Ganz

doi:10.1158/1055-9965.EPI-13-1105-T

DOI: 10.1158/1055-9965.EPI-13-1105-T Published May 2014

Article Figures & Data

Figures

Tables
Additional Files

Download figure
Open in new tab
Download powerpoint
Figure 1.
Kaplan–Meier graph of the time to breast cancer event (A) or colon cancer (B), grouped according to smoking duration. P values are based on multivariable Cox regression analysis.
Download figure
Open in new tab
Download powerpoint
Figure 2.
HRs and 95% CIs for the association of cigarette smoking history with time to invasive cancer of the breast, lung, colon, and endometrium.
Download figure
Open in new tab
Download powerpoint
Figure 3.
HRs and 95% CIs for the association of physical activity with time to invasive cancer of the breast, lung, colon, and endometrium.
Download figure
Open in new tab
Download powerpoint
Figure 4.
HRs and 95% CIs for the association of alcohol consumption with time to invasive cancer of the breast, lung, colon, and endometrium.

Table 1.

Participant characteristics: NSABP P-1

	Placebo	Tamoxifen	Total
	N = 6,707 (50.1%)	N = 6,681 (49.9%)	(N = 13,388)
Characteristic^a	N (%)	N (%)	N (%)
Age, y (B, L, C, E)
<65	5797 (86.4)	5783 (86.6)	11,580 (86.5)
≥65	910 (13.6)	898 (13.4)	1,808 (13.5)
Race (B, L, C, E)
White	6,352 (94.7)	6,337 (94.8)	12,689 (94.8)
Black	133 (2)	143 (2.1)	276 (2.1)
Hispanic	94 (1.4)	73 (1.1)	167 (1.2)
Other/unknown	128 (1.9)	128 (2)	256 (1.9)
Leisure-time physical activity (B, L, C, E)
Moderate–heavy	3,058 (45.6)	3,067 (45.9)	6,125 (45.7)
Inactive–light	3,626 (54.1)	3,586 (53.7)	7,212 (53.9)
Unknown	23 (0.3)	28 (0.4)	51 (0.4)
Baseline BMI (B^b, E^b)
Healthy (BMI < 25)	2,603 (38.8)	2,635 (39.4)	5,238 (39.1)
Overweight (BMI ≥25 to <30)	2,233 (33.3)	2,157 (32.3)	4,390 (32.8)
Obese (BMI ≥ 30)	1,871 (27.9)	1,889 (28.3)	3,760 (28.1)
Alcohol consumption (B, L, C, E)
None	1,421 (21.2)	1,366 (20.5)	2,787 (20.8)
1 drink/day	4,383 (65.3)	4,439 (66.4)	8,822 (65.9)
>1 drink/day	877 (13.1)	847 (12.7)	1,724 (12.9)
Unknown	26 (0.4)	29 (0.4)	55 (0.4)
Smoking status (B, L, C, E)
Never smoked	3,707 (55.3)	3,612 (54.1)	7,319 (54.7)
Current smoker	827 (12.3)	847 (12.7)	1,674 (12.5)
Former smoker	2,150 (32.1)	2,195 (32.8)	4,345 (32.5)
Unknown	23 (0.3)	27 (0.4)	50 (0.4)
Smoking duration (B, L, C, E)
Never smoked^c	3,715 (55.4)	3,620 (54.2)	7,335 (54.8)
<15 smoking years	839 (12.5)	825 (12.3)	1,664 (12.4)
≥15 to <35 smoking years	1,607 (24)	1,707 (25.6)	3,314 (24.8)
≥35 smoking years	514 (7.7)	497 (7.4)	1,011 (7.6)
Unknown	32 (0.5)	32 (0.5)	64 (0.5)
Smoking intensity (B, L, C, E)
None	3,707 (55.3)	3,612 (54.1)	7,319 (54.7)
1 pack/day	2,008 (29.9)	2,069 (31)	4,077 (30.5)
>1 packs/day	968 (14.4)	972 (14.5)	1,940 (14.5)
Unknown	24 (0.4)	28 (0.4)	52 (0.4)
5-Year breast cancer risk (B^d)
≤2%	1,682 (25.1)	1,677 (25.1)	3,359 (25.1)
>2% and ≤5%	3,895 (58.1)	3,823 (57.2)	7,718 (57.6)
>5%	1,130 (16.8)	1,181 (17.7)	2,311 (17.3)
Family cancer history (number of family members who developed cancer; L, C, E)
None	759 (11.3)	731 (10.9)	1,490 (11.1)
1	2,709 (40.4)	2,717 (40.7)	5,426 (40.5)
>1	3,183 (47.5)	3,182 (47.6)	6,365 (47.5)
Unknown	56 (0.8)	51 (0.8)	107 (0.8)
Menstrual period stopped (B, L, C, E)
No	2,254 (33.6)	2,159 (32.8)	4,449 (33.2)
Yes	4,453 (66.4)	4,486 (67.2)	8,939 (66.8)
Estrogen use (B, L, C, E)
Never used	1,619 (24.1)	1,542 (23.1)	3,161 (23.6)
Ever used	5,088 (75.9)	5,139 (76.9)	10,227 (76.4)
Age at menarche (years; E)
7–10	567 (8.5)	576 (8.6)	1,143 (8.5)
11–13	4,868 (72.6)	4,902 (73.4)	9,770 (73)
≥14	1,243 (18.5)	1,180 (17.7)	2,423 (18.1)
Unknown	29 (0.4)	23 (0.3)	52 (0.4)
Ever had diabetes (B, E)
No	6,443 (96.1)	6,402 (95.8)	12,845 (95.9)
Yes	264 (3.9)	279 (4.2)	543 (4.1)
Past pregnancy (E)
No	1,011 (15.1)	1,009 (15.1)	2,020 (15.1)
Yes	5,690 (84.8)	5,669 (84.9)	11,359 (84.8)
Unknown	6 (0.1)	3 (0)	9 (0.1)
Current regular aspirin use (C)
No	5,651 (84.3)	5,610 (84.0)	11,261 (84.1)
Yes	1,056 (15.7)	1,071 (16.0)	2,127 (15.9)
Personal history of tuberculosis (L)
No	6,629 (98.8)	6,581 (98.5)	13,210 (98.7)
Yes	78 (1.2)	100 (1.5)	178 (1.3)

↵^aCharacteristic included in disease site models in parentheses: breast (B), lung (L), colon (C), and endometrial (E).
↵^bOverweight/obesity was included in secondary analyses for models with significant effects of physical activity. These were the models for breast and endometrial cancers.
↵^cIncludes former smokers who indicated 0 years of smoking history.
↵^dEstimated breast cancer risk is included as a continuous variable in models.

Additional Files

Figures
Tables

Supplementary Data

Files in this Data Supplement:

Supplementary Materials and Methods, Supplementary Results, and Supplementary Tables 1 and 2 - PDF - 135K, Appendix providing analyses of alternative smoking variables and interactions. Table A1. Multivariable analysis results (p-values, hazard ratios and 95% confidence intervals) for alternative smoking history variables. Table A2. Hazard ratios (with 95% confidence intervals in parentheses).