Evaluation of osteopenia and osteoporosis in younger breast cancer survivors compared with cancer-free women: a prospective cohort study

Table 2 Risk of incident osteopenia and osteoporosis among breast cancer survivors compared with cancer-free women

	Events/person-years	Age-adjusted HR (95% CI)	MV-adjusted HR (95% CI)^a
Overall
Cancer-free	67/3509	1.00 (reference)	1.00 (reference)
Breast cancer survivors	45/1026	2.01 (1.38–2.94)	1.68 (1.12–2.50)
Excluding women without bone density examinations prior to baseline
Cancer-free	27/1023	1.00 (reference)	1.00 (reference)
Breast cancer survivors	27/497	1.96 (1.15–3.36)	1.90 (1.08–3.34)
Excluding women without bone density examinations during follow-up
Cancer-free	63/1890	1.00 (reference)	1.00 (reference)
Breast cancer survivors	45/703	1.89 (1.29–2.78)	1.72 (1.14–2.58)
Excluding early bilateral oophorectomy prior to baseline^b
Cancer-free	64/3347	1.00 (reference)	1.00 (reference)
Breast cancer survivors	42/957	1.93 (1.30–2.85)	1.63 (1.08–2.46)
Excluding pre- to postmenopausal during follow-up
Cancer-free	34/2308	1.00 (reference)	1.00 (reference)
Breast cancer survivors	32/745	2.18 (1.34–3.55)	1.57 (0.93–2.63)
Excluding current vitamin D users^c
Cancer-free	60/3263	1.00 (reference)	1.00 (reference)
Breast cancer survivors	36/820	2.03 (1.34–3.08)	1.68 (1.08–2.61)
Excluding current calcium users^c
Cancer-free	40/2637	1.00 (reference)	1.00 (reference)
Breast cancer survivors	28/743	2.14 (1.32–3.48)	1.59 (0.95–2.68)

Abbreviations: MV Multivariable
^aAdjusted for age (years), menopausal status (premenopausal, postmenopausal), bilateral oophorectomy at age < 45 years (yes, no), body mass index (kg/m²), physical activity (MET-h/wk), smoking status (never, ever), alcohol intake (g/d), and hormone replacement therapy (never, ever)
^bBoth ovaries removed prior to age 45 years
^cVitamin D and calcium supplement use was ascertained at baseline

ISSN: 1465-542X