Age-related differences in the pathogenesis of calcific aortic stenosis : the potential role of resistin

Abstract

Background: Aortic stenosis (AS) is considered as an atherosclerotic related process. However, there are uncertainties whether AS in the elderly is associated with the same pathophysiological processes as in younger patients. We hypothesized that the metabolic determinants of the valvular inflammatory and calcifying processes occurring in elderly patients are different from those observed earlier in life. Methods: Among 114 patients operated for a severe AS, a complete plasma lipid blood profile and plasma levels of adipokines (resistin, leptin) were determined. The calcium content of the aortic valve was measured and valvular inflammation was quantified. Results Elderly patients (= 70 years) had significantly lower LDL-C ( p = 0.02), lower LDL-C associated with small size particles (LDL-C < 255 Å) ( p = 0.003), and higher HDL peak particle size than younger patients ( p = 0.03). In addition, elderly patients had increased plasma leptin ( p = 0.04) and resistin ( p = 0.0004) levels compared to the middle-aged group (< 70 years). In the elderly patients, higher plasma resistin blood levels were associated with increased valve calcium content and inflammation. Conclusion: The lipid profile of elderly patients was found less atherogenic than that of middle-aged patients. On the other hand, older patients with AS had higher plasma level of resistin which was associated with the degree of valvular calcification and inflammation. These results suggest that, beyond lipid model of atherosclerosis, age-related processes affecting resistin blood levels may also be involved in the late development of AS.