Table 3.

Adjusted odds ratios for young-onset breast cancer associated with menopause-associated symptoms

Characteristics†	Control (n=1669)	Cases (n=1422)	OR (95% CI)‡
	No. (%)	No. (%)
Had any menopause symptoms prior to index age
No	1217 (73.0)	1164(81.9)	1.00
Yes	449 (27.0)	257 (18.1)	0.49 (0.40, 0.61)
Had hot flashes prior to index age
No	1311 (79.1)	1244 (87.8)	1.00
Yes	346 (20.9)	172 (12.2)	0.47 (0.37, 0.60)
Had other symptoms related to menopause prior to index age
No	1310 (78.9)	1200 (84.9)	1.00
Yes	351 (21.1)	214 (15.1)	0.56 (0.45, 0.70)

Missing data: Hot flashes (n=18), other symptoms (n=16), any menopausal symptoms (n=4) Other menopause symptoms: poor sleeping, night sweats, irritability, or depression, etc.

^†Menopause symptoms were defined as ever prior to index age; menopause symptoms reported as first occurring after index age were not treated as relevant.

^‡Adjusted for birth order and menopausal status at index age (premenopausal, postmenopausal, premenopausal hysterectomy with retained ovary tissue)