CYP17 5'-UTR MspA1 polymorphism and the risk of premenopausal breast cancer in a German population-based case–control study

Table 5 Association between some potential risk factors of breast cancer by CYP17 genotype among premenopausal women in Germany

Factor	All data			A1/A1			A1/A2 and A2/A2
	Cases (n = 527)	Controls (n = 904)	OR^a (95% CI)	Cases (n = 180)	Controls (n = 323)	OR^a (95% CI)	Cases (n = 347)	Controls (n = 581)	OR^a (95% CI)
Age at menarche^b
<13 years	186	323	1.00	68	123	1.00	118	200	1.00
≥13 years	338	580	1.00 (0.80–1.27)	112	199	1.01 (0.67–1.51)	226	381	1.00 (0.75–1.34)
Age at menarche, nulliparous women
<13 years	43	64	1.00	17	24	1.00	26	40	1.00
≥13 years	79	135	0.79 (0.48–1.31)	24	46	0.98 (0.38–2.55)	55	89	0.91 (0.47–1.78)
Age at menarche, parous women
<13 years	143	259	1.00	51	99	1.00	92	160	1.00
≥13 years	259	445	1.11 (0.85–1.45)	88	153	1.08 (0.68–1.72)	171	292	1.09 (0.78–1.53)
Pill use^c
Never	85	178	1.00	30	62	1.00	55	116	1.00
Ever	442	724	1.23 (0.91–1.66)	150	260	1.22 (0.72–2.09)	292	464	1.24 (0.86–1.79)
Pill use, nulliparous women
Never	25	48	1.00	10	23	1.00	15	25	1.00
Ever	99	150	1.64 (0.87–3.08)	31	46	2.60 (0.81–8.43)	68	104	1.35 (0.59–3.10)
Pill use, parous women
Never	60	130	1.00	20	39	1.00	40	91	1.00
Ever	343	574	1.26 (0.89–1.80)	119	214	1.10 (0.58–2.09)	224	360	1.35 (0.88–2.05)
Age at first full-term preganancy^d
<25 years	215	352	1.00	69	125	1.00	146	227	1.00
≥25 years	188	353	0.86 (0.66–1.14)	70	128	0.98 (0.60–1.59)	118	225	0.79 (0.56–1.11)
Breastfeeding status^d
Never	116	187	1.00	43	65	1.00	73	122	1.00
Ever	287	518	0.90 (0.68–1.20)	96	188	0.70 (0.43–1.16)	191	330	1.02 (0.71–1.46)
Total months of breastfeeding among parous ever breastfed women
1–12	253	416	1.00	86	156	1.00	167	260	1.00
>12	34	102	0.56 (0.36–0.87)	10	32	0.69 (0.30–1.60)	24	70	0.53 (0.31–0.90)

^aMultivariate adjusted odds ratio (OR) and 95% confidence interval (CI). Adjusted for alcohol consumption (0, 1 to 18, >18 g/day); current body mass index as continuous variable; educational level (low, middle, high); family history of breast cancer in first-degree relative (no, yes); parity (0, 1 to 2 births, 3+ births), and other variables in the table where appropriate. ^bThree cases and one control had missing data. ^cTwo controls had missing data. ^dLimited to parous women.

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