Table 1.

Characteristics of Women With Early-Stage Breast Cancer Who Self-Reported Discontinuing Endocrine Therapy (stopping treatment before 5 years) Compared With Those Who Did Not

Characteristic	Did Not Discontinue		Discontinued		OR*	95% CI†
	No.	%	No.	%
No. of patients	440		98
Endocrine therapy use
Tamoxifen only	126	28.6	43	43.9	1	Reference
AIs only	168	38.2	22	22.4	0.45	0.25 to 0.83†
Both	146	33.2	33	33.7	0.63	0.36 to 1.10
Age at diagnosis, years
Mean	64		65
SD	8.4		9.7
52-59	158	35.9	34	34.7	1	Reference
60-69	174	39.5	36	36.7	1.04	0.61 to 1.78
70-79	88	20.0	20	20.4	1.27	0.67 to 2.41
≥ 80	20	4.5	8	8.2	2.25	0.86 to 5.86
Race
White	394	90.2	89	90.8	1	Reference
Other	43	9.8	9	9.2	1.14	0.52 to 2.52
Missing	3		0
Education
High school or less	73	19.2	13	14.9	1	Reference
Some college	143	37.5	33	37.9	1.49	0.71 to 3.14
College graduate	76	19.9	17	19.5	1.41	0.61 to 3.28
Post-college	89	23.4	24	27.6	1.72	0.78 to 3.79
Missing	59		11
Household income, $
≤ 25,000	53	14.4	14	16.5	1	Reference
25,001-50,000	135	36.8	36	42.4	1.37	0.64 to 2.94
50,001-100,000	129	35.1	26	30.6	0.99	0.43 to 2.23
> 100,000	50	13.6	9	10.6	1.02	0.35 to 2.92
Missing	73		13
BMI, kg/m2
Mean	31		29
SD	9.8		5.9
< 25.0	92	29.4	19	26.8	1	Reference
25.0-29.9	102	32.6	27	38.0	1.23	0.61 to 2.49
≥ 30.0	119	38.0	25	35.2	1.29	0.63 to 2.62
Missing	127		27
Stage at diagnosis
I	242	55.0	62	63.3	1	Reference
IIA	139	31.6	25	25.5	0.67	0.39 to 1.14
IIB	59	13.4	11	11.2	0.63	0.30 to 1.18
Tumor size, mm
< 10	72	16.4	20	20.4	1	Reference
10-19	240	54.5	49	50.0	0.59	0.32 to 1.10
≥ 20	128	29.1	29	29.6	0.6	0.30 to 1.18
Lymph node status
Negative	296	67.3	77	78.6	1	Reference
Positive	144	32.7	21	21.4	0.54	0.31 to 0.93†
Charlson score
0	344	78.2	83	84.7	1	Reference
1	63	14.3	11	11.2	0.73	0.35 to 1.49
≥ 2	33	7.5	4	4.1	0.58	0.19 to 1.80
Year of diagnosis
2002-2004	152	34.5	63	64.3	1	Reference
2005-2008	288	65.5	35	35.7	0.29	0.18 to 0.45†

Abbreviations: BMI, body mass index; OR, odds ratio; SD, standard deviation.

^*Adjusted for age and year of diagnosis.

^†P < .05.