['Hostility may be associated with greater systemic inflammation. However, contradictory evidence exists. Certain individuals or dimensions of hostility may be more susceptible to these effects. Main and interactive effects of hostility with sex and/or age were evaluated on markers of inflammation, independently of traditional risk factors for coronary artery disease.', '199 healthy men (81) and women (118), aged 20-64 years (M=41 ± 11 years) were recruited. Hostility was assessed using the Cook-Medley Hostility Inventory (CMHo) and ecological momentary assessments (EMA) of quarrelsome behavior and angry affect in daily living. Blood samples were drawn to measure inflammatory activity (Il-6, TNF-α, hsCRP, Il-8, Il-10, Il-18, MCP-1) and lipid oxidation (Myeloperoxidase; MPO). Correlations and hierarchical regression analyses were performed controlling for pertinent behavioral, psychological, medical, and socio-demographic factors.', 'Significant univariate associations emerged between CMHo and Il-6, TNF-α, MCP-1 (p<.05). Hierarchical regressions showed interactions of hostility with sex (Il-6, TNF-α; p<.05) and age (hsCRP, Il-6, TNF-α; p<.05). For example, in simple slope analyses, hostility was positively related to TNF-α in women (b=0.009, p=0.006) but not men. Greater hostility was also related to greater Il-6 levels among younger women (b=. 027, p=0.000).'] Is the relation between hostility and concurrent levels of inflammation sex , age , and measure dependent?