Evaluating blood pressure response during exercise rather than during rest might better detect a subtle impairment in relaxation of the resistance vessel in hypercholesterolemia. We examined the relation between serum cholesterol and blood pressure response during exercise in patients with coronary artery disease. One hundred and forty-eight consecutive patients with coronary artery disease were monitored during symptom-limited incremental exercise testing with a cycle ergometer. Cuff blood pressure was measured every minute during exercise testing with an automatic indirect manometer. Although there were no significant differences in systolic or diastolic blood pressure at rest between the patients with hypercholesterolemia (total cholesterol > or = 220 mg/dL, n = 39) and those without it (n = 109), the former reached a higher diastolic blood pressure at peak exercise (94.8+/-16.0 versus 87.8+/-12.9 mmHg, P = 0.007). The increase in diastolic blood pressure at peak exercise versus the resting value in the patients with hypercholesterolemia was 20.6+/-11.3 mmHg, and this was significantly higher than the increase in patients without hypercholesterolemia (14.8+/-11.8 mmHg, P = 0.009). However, there were no differences in the peak exercise systolic blood pressure and the magnitude of the increase in systolic blood pressure between the two groups. Among the patients with coronary artery disease in our study, we found that those with hypercholesterolemia had significantly higher diastolic blood pressure during exercise than those without hypercholesterolemia, strongly suggesting that patients with hyperlipidemia are at a higher risk of developing hypertensive complications.