TABLE I.

Demographic and Clinical Characteristics of Prostate Cancer Cases and Controls

	Cases (N = 527)	Controls (N = 558)
Continuous variables	Mean (SD)	Mean (SD)	P-valuea
Age, years	63.4 (9.3)	56.8 (10.6)	<0.001***
Body-mass index, (kg/m2)	27.9 (8.6)	29.6 (10.6)	0.02*
Income, $ 000	43.7 (29.5)	48.8 (28.8)	0.02*
Prostate-specific antigen (ng/ml)	81.5 (615.2)	1.2 (1.1)	0.02*

Categorical variables	%	%	P-valueb
Cigarette-use
Never Smoker	44.3	50.3	0.16*
Current Smoker	30.4	28.2
Former Smoker	25.2	21.5
Heavy smoking
Greater than 20 cigarettes per day	14.8	21.1	0.04*
Alcohol-use
Ever	77.6	74.7	0.29*
Alcohol Frequency
Greater than 10 drinks per week	14.8	10.5	0.04*
Education
High school diploma or equivalent	84.8	94.3	<0.001***
Marital status
Married	29.7	22.2	0.01
Poverty
Less than $20,000	37.2	26.9	0.003
Obesity
Obese (BMI ≥ 30)	24.8	34.9	0.003**
Race
African American	79.9	71.3
European American	20.1	28.7	0.001**

Tumor characteristics	%
Gleason score
4–6	54.3
7c	30.4
8–10	15.3
NCCN risk category
Low-risk	39.2
Intermediate	30.3
High-risk	30.6

^aUnpaired, two-sample t-test.

^bChi-square analysis; BMI, body mass index; TNM, Tumor node metastasis staging.

^cIncludes both Gleason 3 + 4 and Gleason 4 + 3 tumors.

^*P < 0.05.

^**P < 0.01.

^***P < 0.001.