Table 4.

Multivariate relative risks of cholecystectomy in relation to statin use according to selected risk factors among US women in the Nurses’ Health Study^a

Variables	Nonuse (referent)	Current use Multivariate relative risk (95% C.I.)b
		< 2 years	≥ 2 years	Total
Diabetes
Yes	1.00	0.67 (0.37, 1.21)	0.25 (0.07, 0.88)	0.53 (0.31, 0.93)
No	1.00	0.82 (0.67, 1.01)	0.85 (0.64, 1.13)	0.83 (0.70, 0.99)
Diuretic use
Yes	1.00	0.68 (0.40, 1.16)	0.72 (0.34, 1.52)	0.69 (0.44, 1.08)
No	1.00	0.84 (0.69, 1.04)	0.83 (0.62, 1.12)	0.84 (0.70, 0.99)
Body mass index (kg/m2)
< 30	1.00	0.90 (0.72, 1.14)	0.88 (0.64, 1.21)	0.89 (0.74, 1.08)
≥ 30	1.00	0.79 (0.55, 1.13)	0.87 (0.50, 1.50)	0.81 (0.60, 1.09)
Weight change within past 2 yrs
> 4 lb	1.00	1.03 (0.74, 1.44)	0.47 (0.21, 1.02)	0.88 (0.64, 1.20)
≤ 4 lb	1.00	0.82 (0.64, 1.05)	0.99 (0.73, 1.34)	0.88 (0.72, 1.07)
Current smoking
Yes	1.00	0.79 (0.42, 1.50)	0.83 (0.32, 2.12)	0.80 (0.47, 1.38)
No	1.00	0.83 (0.68, 1.01)	0.82 (0.62, 1.09)	0.82 (0.69, 0.97)
Current age
< 60	1.00	0.59 (0.40, 0.88)	0.79 (0.46, 1.37)	0.65 (0.47, 0.90)
≥ 60	1.00	0.93 (0.75, 1.16)	0.81 (0.60, 1.12)	0.89 (0.75, 1.08)
Physical activityc (METs)
High	1.00	0.88 (0.70, 1.11)	0.85 (0.62, 1.18)	0.87 (0.72, 1.05)
Low	1.00	0.74 (0.52, 1.05)	0.70 (0.42, 1.18)	0.73 (0.54, 0.98)
Coffee intakec
High	1.00	0.89 (0.70, 1.13)	0.77 (0.52, 1.12)	0.85 (0.69, 1.04)
Low	1.00	0.74 (0.54, 1.02)	0.89 (0.60, 1.34)	0.79 (0.61, 1.02)

^aThe multivariate model included the same covariates as in model 2 in table 2. In each case, the stratification variable was excluded from the model. Within each stratum, the group without use of statins served as the reference group.

^bC.I. = confidence interval

^cMedian values were used as cut-off point.