BACKGROUND: Elevated serum cholesterol levels are associated with increased risk for acute myocardial infarction (AMI) and adverse patient outcomes. It is unclear what proportion of patients have their serum cholesterol levels measured during hospitalization for AMI and are given hypolipidemic therapy. OBJECTIVE: To examine decade-long trends in measurement of serum cholesterol levels during hospitalization for AMI and use of hypolipidemic therapy. METHODS: Observational study of 5204 residents of the Worcester, Mass, metropolitan area hospitalized with validated AMI in all greater Worcester hospitals in seven 1-year periods from 1986 through 1997. RESULTS: Increases in the measurement of serum cholesterol levels during hospitalization for AMI were observed between 1986 and 1991, followed by a progressive decrease; only 24% of patients with AMI in 1997 underwent cholesterol level testing. Younger age, male sex, and absence of a history of cardiovascular disease were associated with an increased likelihood measurement of serum cholesterol levels. Although the relative use of hypolipidemic therapy increased significantly over time (0.4% in 1986 vs 10.7% in 1997), the absolute rate of use remained low. In patients with elevated serum cholesterol levels (>/=6.2 mmol/L [>/=240 mg/dL]), 1.9% received hypolipidemic therapy in 1986 and 36.6% in 1997. CONCLUSIONS: These findings suggest recent declines in the assessment of total cholesterol levels in patients hospitalized with AMI. Although the use of hypolipidemic therapy during hospitalization for AMI has increased over time, considerable room for improvement remains.