Table 4.

Associations of imputed body mass index (BMI) at age 10, early life BMI change, and adulthood BMI change with risk of epithelial ovarian cancer for serious and non-serous subtypes

	Non-serous			Serous			P-hetb
	Cases	P-Ys	HR (95% CI)a	Cases	P-Ys	HR (95% CI)a
Imputed BMI at age 10
<14.0	37	233 707	1.00 (ref)	64	233 707	1.00 (ref)	0.65
14.0–15.9	75	528 385	0.94 (0.63–1.42)	140	528 385	1.00 (0.73–1.35)
16.0–17.9	60	434 118	0.96 (0.62–1.50)	99	434 118	0.96 (0.69–1.35)
18.0–19.9	34	189 001	1.33 (0.80–2.22)	51	189 001	1.28 (0.86–1.92)
≥20.0	15	185 023	0.65 (0.33–1.28)	44	185 023	1.25 (0.80–1.96)
Per 5 BMI units			0.96 (0.74–1.26)			1.04 (0.85–1.27)
P-trend			0.79			0.72
BMI change between age 10 and18
<2.0	25	294 095	0.56 (0.34–0.92)	55	294 095	0.73 (0.51–1.05)	0.10
2.0–3.9	60	372 078	1.00 (ref)	89	372 078	1.00 (ref)
4.0–5.9	55	421 995	0.82 (0.56–1.19)	123	421 995	1.19 (0.90–1.58)
6.0–7.9	41	276 541	0.92 (0.60–1.40)	86	276 541	1.25 (0.91–1.72)
≥8.0	40	205 525	1.14 (0.74–1.77)	45	205 525	0.91 (0.62–1.33)
Per 5 BMI units			1.35 (1.10–1.65)			1.08 (0.90–1.28)
P-trend			0.004			0.42
BMI change since age 18
<−2.0	13	61 383	1.49 (0.79–2.81)	17	61 383	0.98 (0.58–1.67)	0.06
−2.0 to 1.9	53	463 965	1.00 (ref)	97	463 965	1.00 (ref)
2.0–3.9	45	334 053	1.14 (0.77–1.70)	86	334 053	1.14 (0.85–1.53)
≥4.0	110	710 833	1.22 (0.87–1.70)	198	710 833	1.04 (0.81–1.33)
Per 5 BMI units			1.14 (1.00–1.30)			0.97 (0.87–1.08)
P-trend			0.04			0.61

^aStratified by calendar time, mutually controlling for imputed BMI at age 10, BMI change between age 10 and 18 and BMI change since age 18, and adjusted for age at menarche, tubal ligation, duration of OC use, duration of premenopause, duration of postmenopause, menopausal status, type of menopause, duration of estrogen-only HT use, duration of estrogen and progesterone HT use, duration of other HT use, height, parity and smoking status.

^bTest for heterogeneity between serous versus non-serous ovarian cancer. P-Y, person-years; HT, hormone therapy.