Objective: To investigate whether stimulated monocyte cytokine release and its inhibition by glucocorticoids differs between men and women. Design: In vitro m onocyte interleukin 6 (IL-6) and tumour necrosis factor α(TNFα) release after lipopolysaccharide stimulation were assessed with and without co-incubation with increasing doses of dexamethasone and hyd rocortisone separately. Glucocorticoid sensitivity was defined as the amount of a particular glucocorticoid required to inhibit lipopolysaccharide stimulated mo nocyte cytokine release by 50%. The established cardiovascular risk factors of age, body mass index, number of cigarettes smoked daily, low density cholesterol to high density cholesterol ratio, systolic and diastolic blood pressure, and h aemoglobin A1c were used as covariates. Setting: Aircraft manufacturing plant in southern Germany. Patients: 269 middle aged male and 36 middle aged female empl oyees. Results: Release of monocyte IL-6 and TNFα(each p=0.001) was higher in samples from men than in those from women. Inhibition of lipopolysaccharide stim ulated IL-6 and TNFαrelease by either glucocorticoid was less pronounced in sa mples from men than in those from women (IL-6: dexamethasone p=0.033, hydrocort isone p=0.029; TNFα: dexamethasone p< 0.001, hydrocortisone p=0.089). Conclusio ns: The finding suggests that proinflammatory activity of circulating monocytes is higher in men than in women independent of cardiovascular risk factors, there by providing one explanation for the relatively greater coronary risk in men. Objective: To investigate whether stimulated monocyte cytokine release and its inhibition by glucocorticoids Differences between men and women. Design: In vitro m onocyte interleukin 6 (IL-6) and tumor necrosis factor α (TNFα) release after lipopolysaccharide stimulation were assessed with and without co-incubation with increasing doses of dexamethasone and hydocorticone release by 50%. Glucocorticoid sensitivity was defined as the amount of a particular glucocorticoid required to inhibit lipopolysaccharide stimulated mo nocyte cytokine release by 50%. The established cardiovascular risk factors of age, body mass index, number of cigarettes smoked daily, low density cholesterol to high density cholesterol ratio, systolic and diastolic blood pressure, and h aemoglobin A1c were used as covariates. Patients: 269 middle aged male and 36 middle aged female empl Results: Release of monocyte IL-6 and TNFα (each p = 0.001) was higher in samples from men than in those from women. Inhibition of lipopolysaccharide stimulant IL-6 and TNFα release by either glucocorticoid was less pronounced in sa mples from men than those from women (IL-6: dexamethasone p = 0.033, hydrocort isone p = 0.029; TNFα: dexamethasone p <0.001, hydrocortisone p = 0.089). Conclusio ns: The finding suggests that proinflammatory activity of circulating monocytes is higher in men than in women independent of cardiovascular risk factors, there by providing one explanation for the relatively greater coronary risk in men.