Table 3.

Passive smoking and risk of pancreatic cancer in the Nurses' Health Study 1982–2006, among never-active smokers

Passive smoking	Cases	Person-years	Age-adjusted RR (95% CI)	Multivariable RR (95% CI)*
Parental smoking
Neither parent	65	312069	1.0 (Reference)	1.0 (Reference)
Mother†	30	143471	1.57 (1.01–2.46)	1.52 (0.97–2.39)
Father†	68	458754	0.77 (0.55–1.08)	0.76 (0.54–1.07)
Unknown	8	58464	0.68 (0.33–1.43)	0.64 (0.31–1.34)
Currently exposed at work or home
None	18	129157	1.0 (Reference)	1.0 (Reference)
Occasionally	78	446664	0.84 (0.54–1.32)	0.81 (0.52–1.26)
Regularly, work or home	24	140198	1.21 (0.76–1.92)	1.13 (0.71–1.79)
Regularly, work and home	10	44866	1.30 (0.63–2.68)	1.13 (0.55–2.33)
Unknown	21	99351	0.79 (0.36–1.73)	0.71 (0.32–1.56)
Years lived with smoker as adult
<5	66	433865	1.0 (Reference)	1.0 (Reference)
5–19	34	185236	1.17 (0.77–1.77)	1.17 (0.77–1.77)
20–29	20	108942	0.94 (0.57–1.56)	0.90 (0.54–1.49)
30+	22	70090	1.12 (0.68–1.85)	1.06 (0.64–1.75)
Unknown	9	62103	0.85 (0.42–1.71)	0.79 (0.39–1.60)

^*Multivariate models adjusted for age, height (quintiles), diabetes (yes/no), and BMI (quintiles).

^†Included 4,869 women (20 cases) whose both parents were smokers.