Table 2.

Adverse events associated with endocrine therapy in the NSABP^a B-35 and IBIS^b-II trials

NSABP B-35†
	Anastrozole	Tamoxifen	ORc (95%CId)	P value
	N=1539	N=1538
Endometrial cancer	8 (0.5%)	17 (1.1%)	0.47 (0.18–1.15)	NSe
Osteoporotic fractures	69 (4.4%)	50 (3.3%)	1.38 (0.95–2.03)	NS
Arthralgia‡	504 (33%)	358 (23%)	–	–
Thromboembolic events‡	12 (0.8%)	41 (2.7%)	–	–
IBIS-II
	Anastrozole	Tamoxifen	OR (95% CI)	P value
	N=1449	N=1489
Endometrial cancer	1 (0.06%)	11 (0.7%)	0.09 (0.002–0.64)	0.0044
Osteoporotic fractures	129 (9%)	100 (7%)	1.36 (1.03–1.80)	0.027
Arthralgia	832 (57%)	729 (49%)	1.41 (1.21–1.63)	< 0.0001
Hot flashes	818 (56%)	899 (60%)	0.85 (0.73–0.99)	0.031
Vaginal dryness	189 (13%)	159 (11%)	1.25 (1.00–1.58)	0.047
Vaginal discharge	30 (2%)	136 (9%)	0.21 (0.14–0.32)	< 0.0001
Thromboembolic events	7 (< 1%)	24 (2%)	0.30 (0.11–0.71)	0.0028
Cardiovascular events	93 (6%)	84 (6%)	1.15 (0.84–1.57)	0.38
Cataracts	72 (5%)	61 (4%)	1.22 (0.85–1.77)	0.26

^†p values were not included for NSABP B-35

^‡information about adverse events available for 3070 patients (1535 in each treatment arm)

^aAbbreviation: NSABP, National Surgical Adjuvant Breast and Bowel Project

^bAbbreviation: IBIS, International Breast Cancer Intervention Studies

^cAbbreviation: OR, odds ratio for women in the anastrozole group compared with those in the tamoxifen group

^dAbbreviation: CI, confidence interval

^eAbbreviation: NS, non-significant

Adapted with data from Margolese et al and Forbes et al (34, 35).

Note to Editor: This table was created by the authors using data from these 2 cited references. If permission to do so is required beyond this credit line, please notify the authors.