Table 2.

Factors associated with JC virus (JCV) infection among controls, Washington County, MD, 1975 to 2006

	JCV-positive		JCV-negative
Characteristic	n	%	n	%	p-value
Sex
male	266	70.0	114	30.0
female	341	72.2	131	27.8	0.48
Age (years)
< 35	30	83.3	6	16.7
35–44	67	72.8	25	27.2
45–54	173	70.9	71	29.1
55–64	172	67.5	83	32.5
65–74	123	73.2	45	26.8
75+	34	69.4	15	30.6	0.09
Smoking status
current	125	74.0	44	26.0	0.871
former	156	65.5	82	34.5	0.031
never	326	73.3	119	26.7
Body mass index (kg/m2)2
< 25	91	58.7	64	41.3
25–30	81	49.4	83	50.6
30+	25	41.0	36	59.0	0.05
NSAID use at baseline (past 48 hours)3
yes	174	28.7	64	26.1
no	433	74.3	181	73.9	0.45
Family history of colorectal cancer2
no	127	51.2	121	48.8
yes	22	52.4	20	47.6	1.00
Recent hormone use2
none	83	50.0	83	50.0
any	19	54.3	16	45.7	0.71

¹p-values correspond to comparison between current versus never smokers and former versus never smokers

²data obtained from CLUE II participants only

³NSAID use within 48 hours prior to blood draw