Factors associated with initiation and continuation of endocrine therapy in women with hormone receptor-positive breast cancer

Table 2 Characteristics of the pooled sample and prevalence of ET initiation by the 12-month interview and ET continuation for at least 12 months after initiation among hormone receptor-positive breast cancer patients

	ET initiation^a				ET continuation^b
Independent variables	Total N	Yes n (%)	No n (%)	P^c	Total n	Yes n (%)	No n (%)	P^c
Total	533	434 (81.4)	99 (18.6)		410	370 (90.2)	40 (9.8)
Race
White	311	259 (83.3)	52 (16.7)	0.19	248	226 (91.1)	22 (8.9)	0.45
Black/Other^d	222	175 (78.8)	47 (21.2)		162	144 (88.9)	18 (11.1)
Age, years
Mean (SD)	58.1 (10.6)	57.8 (10.2)	59.5 (11.8)	0.15	57.8 (10.2)	57.7 (10.3)	59.3 (9.3)	0.32
Insurance status
Private	389	320 (82.3)	69 (17.7)	0.41	307	279 (90.9)	28 (9.1)	0.45
Public only or other^e	144	114 (79.2)	30 (20.8)		103	91 (88.4)	12 (11.6)
Chemotherapy
No	380	293 (77.1)	87 (22.9)	<.01	275	246 (89.4)	29 (10.6)	0.44
Yes	153	141 (92.2)	12 (7.8)		135	124 (91.8)	11 (8.2)
Radiation Therapy
No	165	108 (65.4)	57 (34.6)	<.01	101	89 (88.1)	12 (11.9)	0.41
Yes	368	326 (88.6)	42 (11.4)		309	281 (90.9)	28 (9.1)
Diabetes
No	447	373 (83.4)	74 (16.6)	<.01	350	317 (90.6)	33 (9.4)	0.59
Yes	86	61 (70.9)	25 (29.1)		60	53 (88.3)	7 (11.7)
Obesity
No (BMI < 30 kg/m²)	307	249 (81.1)	58 (18.9)	0.83	238	215 (90.3)	23 (9.7)	0.94
Yes (BMI ≥ 30 kg/m²)	226	185 (81.9)	41 (18.1)		172	155 (90.1)	17 (9.9)
Elevated depressed mood
No (CESD < 16)	422	343 (81.3)	79 (18.7)	0.87	339	311 (91.7)	28 (8.3)	0.03
Yes (CESD ≥16)	111	91 (82.0)	20 (18.0)		71	59 (83.1)	12 (16.9)
Menopausal-symptom severity, mean (SD)	1.8 (0.9)	1.8 (0.9)	1.6 (0.8)	0.04	2.1 (0.9)	2.0 (0.9)	2.4 (1.1)	0.02
Change in menopausal-symptom severity^f, mean (SD)	–	–	–	–	0.05 (0.75)	0.07 (0.72)	−0.08 (0.95)	0.37

ET endocrine therapy, SD standard deviation, BMI body mass index, CESD Center for Epidemiologic Studies Depression scale
^a Using diabetes, obesity, elevated depressed mood, and menopausal symptoms from the interview prior to first report of ET use. For non-initiators and patients who first reported ever taking ET at baseline, the baseline measures of these four variables were used
^b Using diabetes, obesity, elevated depressed mood, and menopausal symptom data from the interview when ET initiation was first reported. Of 434 patients who initiated ET within first 12 months of the study, five were excluded due to missing data for obesity and diabetes, and 19 were excluded due to missing data for menopausal symptom severity at follow-up interviews
^c Group differences were tested using independent t-tests for continuous variables and chi-square tests for categorical variables
^d This category includes 216 black, two Asian Indian/Pakistani, two Asian/Pacific Islander, and two unspecified race in the ET initiation model, with one fewer Asian/Pacific Islander in the ET continuation model
^e Other insurance status includes no insurance or self-pay
^f Change in menopausal-symptom severity mean scores from patient’s first reported use of ET to 12-18 month follow-up of ET continuation among patients who had used ET within 12 months of definitive surgery

ISSN: 1471-2407