Antiinflammatory effects of angiotensin II subtype 1 receptor blockade in hypertensive patients with microinflammation

Abstract

Background: Experimental studies revealed proinflammatory properties of angiotensin II. We evaluated antiinflammatory effects of the angiotensin II subtype 1 receptor antagonist olmesartan medoxomil alone and in cotherapy with the HMG-CoA reductase inhibitor pravastatin in patients with essential hypertension and microinflammation.

Methods and results: We measured a panel of vascular inflammation markers, including high-sensitivity C-reactive protein, and lipid levels during 12 weeks of therapy with olmesartan (n=100) or placebo (n=99) in a prospective double-blind multicenter study. Pravastatin was added to the double-blind therapy at week 6 in both treatment arms. Blood pressure control was achieved with addition of hydrochlorothiazide. Olmesartan treatment had already significantly reduced serum levels of high-sensitivity C-reactive protein (-15.1%; P<0.05), high-sensitivity tumor necrosis factor-alpha (-8.9%; P<0.02), interleukin-6 (-14.0%; P<0.05), and monocyte chemotactic protein-1 (-6.5%; P<0.01) after 6 weeks of therapy, whereas placebo treatment (ie, blood pressure reduction) had no major effect on inflammation markers. After 12 weeks of therapy, high-sensitivity C-reactive protein (-21.1%; P<0.02), high-sensitivity tumor necrosis factor-alpha (-13.6%; P<0.01), and interleukin-6 (-18.0%; P<0.01) decreased further with olmesartan and pravastatin cotherapy, but treatment with pravastatin alone (ie, cotherapy with placebo) did not significantly alter inflammation markers. In contrast, addition of pravastatin led to a significant (P<0.001) reduction in LDL cholesterol serum concentrations in the olmesartan and placebo treatment groups (-15.1% and -12.1%, respectively).

Conclusions: Angiotensin II receptor blockade significantly reduces vascular microinflammation in patients with essential hypertension by as early as week 6 of therapy. This antiinflammatory action of angiotensin II receptor antagonists may contribute to their beneficial cardiovascular effects.