OBJECTIVE To assess whether neopterin concentrations in women with unstable angina differ from those in women with chronic stable angina.

DESIGN Prospective cohort study.

SETTING University hospital in south west London.

PATIENTS 114 consecutive women with angina were studied: 82 had chronic stable angina (typical exertional chest pain, positive exercise ECG testing, and/or abnormal myocardial scintigraphy; symptoms stable for at least three months), and 32 had unstable angina (Braunwald class III). All patients with chronic stable angina (100%) and 18 with unstable angina (56.3%) underwent digital coronary angiography; neopterin concentrations were determined using a commercially available immunoassay.

MAIN OUTCOME MEASURES Major clinical events during one year follow up were readmission with Braunwald's class IIIb unstable angina, non-fatal myocardial infarction, and cardiac death.

RESULTS Major events occurred in 12 women with chronic stable angina (14.6%) and nine women with unstable angina (28.1%). Mean (range) neopterin concentrations were significantly higher in women with unstable angina than in those with chronic stable angina (7.6 (5.1–11.5) nmol/l v 5.9 (4.4–7.5) nmol/l; p = 0.003), even after adjustment for variables which were significantly different on univariate analysis. In women with chronic stable angina, baseline neopterin concentrations were higher in those with cardiac events than in those without events (7.1 (5.9–9.1) nmol/l v 5.7 (3.9–7.3 nmol/l); p = 0.010), even after adjustment for variables with significant differences between both groups on univariate analysis.

CONCLUSIONS On average, women with unstable angina had significantly higher neopterin concentrations than women with chronic stable angina. Women with chronic stable angina with events during follow up had higher neopterin concentrations than those without events. Neopterin concentrations were similar in patients with unstable angina and women with chronic stable angina who developed events. Neopterin concentrations may therefore be a marker of risk in women with coronary artery disease.