1. Baseline characteristics of study participants.

Characteristic	Placebo (n=2 257)	Aspirin (n=2 267)
Age (years)	54.9±7.9	54.8±8.1
Male	89.4%	88.4%
Ethnicity
White	91.5%	91.7%
Black	5.9%	6.3%
Hispanics	2.6%	2.0%
BMI	26.0±3.5	25.9±3.5
Diabetes	2.8%	2.5%
Smoking
Never	27.2%	27.5%
Former	5.4%	5.3%
Current	19.2%	19.7%
Alcohol consumption
Daily drink (>1.5 ounces)	15.4%	15.9%
Laboratory results
Platelet count (×109 /L)	253±70	257±70
AST (IU/L)	32±34	31±15
ALP (IU/L)	62±22	64±23
Bilirubin (mg/dL)	0.7±0.3	0.7±0.3
APRI	0.34±0.46	0.33±0.22