Table 1.

Baseline Characteristics, Bone Mineral Density, and Bone Turnover

Variable	PBO (n = 44)		RIS (n = 43)		P
	No.	%	No.	%
Age, years	49 ± 5.9		50.1 ± 5.1		.52
Years postmenopausal	3.2 ± 2.0		3.4 ± 2.0		.61
Body mass index, kg/m2	27.1 ± 5.2		28.3 ± 6.3		.35
Dietary calcium, mg/d	691 ± 347		755 ± 513		.50
Breast cancer treatment
Chemotherapy	44	100	43	100	NA
Lumpectomy	27	61.4	28	65.1	.83
Mastectomy	20	45.5	21	48.8	.83
Radiation therapy	32	72.7	31	72.1	1.00
Tamoxifen, toremifene citrate, or fulvestrant	30	68.2	32	74.4	.64
Aromatase inhibitor	6	13.6	8	18.6	.57
Bone metabolism
Calcium, mg/dL	9.1 ± 1.8		9.2 ± 0.4		.57
25-hydroxyvitamin D, ng/mL	29.3 ± 14.6		30.8 ± 18.9		.68
Parathyroid hormone, pg/mL	45.3 ± 21.0		52.6 ± 23.9		.14
Bone mineral density, g/cm2
Posteroanterior lumbar spine	0.995 ± 0.127		0.985 ± 0.119		.70
Lateral lumbar spine	0.737 ± 0.094		0.727 ± 0.098		.64
Total hip	0.901 ± 0.103		0.910 ± 0.094		.66
Femoral neck	0.768 ± 0.099		0.785 ± 0.105		.43
T-score (± standard deviation)
PA spine	−0.50 ± 1.15		−0.61 ± 1.1		.84
Total hip	−0.37 ± 0.81		−0.28 ± 0.75		.44
Femoral neck	−0.77 ± 0.85		−0.59 ± 0.93		.24
Bone turnover marker
Urinary NTX, nmole BCE/mmol creatinine	38.9 ± 17.6		46.9 ± 28.6		.12
Osteocalcin, ng/mL	18.2 ± 7.3		20.7 ± 7.0		.11
P1NP, μg/mL	49.4 ± 23.2		61.6 ± 23.8		.02

Abbreviations: PBO, placebo; RIS, risedronate; PA, posterior anterior; NTX, N-telepeptide crosslinked collegen type 1; P1NP, N-terminal propeptide of type 1 procollagen.