Table 2.

Association between shiftwork and total prostate-specific antigen (PSA) of 4.0ng/mL or greater and between shiftwork and total PSA of 4.0ng/mL or greater with free PSA less than or equal to 25%*

Exposure	Total PSA ≥ 4.0, odds ratio (95% CI)	P†
Shiftwork, age-adjusted	2.48 (1.08 to 5.70)	.03
Shiftwork, confounder adjusted‡	2.62 (1.16 to 5.95)	.02
	Total PSA ≥ 4.0, free PSA ≤ 25%, odds ratio (95% CI)	P†
Shiftwork, age-adjusted	3.10 (1.32 to 7.31)	.01
Shiftwork, confounder adjusted‡	3.13 (1.38 to 7.09)	.01

* CI = confidence interval.

† All statistical tests were two-sided; P values were calculated using logistic regression models. Nonshiftworkers were the reference group.

‡ Adjusted for age (continuous), body mass index (continuous), race (white, black, Hispanic, other), health insurance (yes/no), hours of sleep per night (continuous), and months on the current job (continuous).