Arterial Stiffness and Bone Demineralization: The Baltimore Longitudinal Study of Aging

BACKGROUND Arterial stiffening is one of the hallmarks of vascular aging, and is an important risk factor for cardiovascular morbidity and mortality. Aging is also associated with bone demineralization. Accumulating evidence indicate that arterial stiffness and bone demineralization might share common pathways. The aims of this study were to evaluate whether the association between arterial stiffness and bone demineralization is independent of age, and to explore putative mechanisms that may mediate their relationship. METHODS A cross-sectional analysis was performed using data from 321 men (68 +/- 12 years) and 312 women (65 +/- 13 years) of the Baltimore Longitudinal Study of Aging. Arterial stiffness was assessed by carotid-femoral pulse wave velocity (PWV) and cross-sectional cortical bone area (cCSA) was assessed at the level of the mid-tibia with computed tomography (CT) imaging. RESULTS Age was significantly correlated with PWV in men (r = 0.38, P < 0.0001) and women (r = 0.35, P < 0.0001). Age was associated with cCSA in women (r = -0.14, P = 0.0008), but not in men. Age-adjusted linear regression analysis showed a significant inverse association between PWV and cCSA, in women but not in men. The association between PWV and cCSA remained significant in women after adjusting for age, mean arterial pressure (MAP), obesity, menopause, drugs, alcohol intake, physical activity, renal function, serum calcium, and total estradiol concentration. CONCLUSIONS Independent of age and other shared risk factors, arterial stiffness is inversely related to cortical bone area in women. The sex-specific signaling and molecular pathways that putatively underlie the cross-talk between central arteries and bone are not completely understood.