Objective
Osteoporosis and cardiovascular disease (CVD) share common risk factors; both often remain undiagnosed until a major life-threatening event occurs. We investigated the associations between rate pressure product (RPP), a surrogate of cardiac workload, or pulse pressure (PP), a measure of arterial stiffness, and bone health in Australian men and women.
Method
Participants were men (n=832) and women (n=764) from recent follow-up visits of the Geelong Osteoporosis Study (men:2006-2011; women:2010-2014). DXA scans (Lunar Prodigy) were performed at the hip and spine (L2-L4). Blood pressure and heart rate were measured (seated) to calculate RPP and PP. All variables were mean-standardised by sex. Linear regression models were sex-stratified; BMD at the total hip or spine were the dependent variables and RPP or PP the independent variables. Adjustments were made for sex, age, height, weight, alcohol consumption, current smoking, physical activity and use of medications (glucocorticoids, bisphosphonates, antihypertensives, statins).
Results
Median age was 60.4yr (IQR 47.6-73.4) for men and 55.7yr (IQR 43.1-68.0) for women. Data for all models are shown in Table 1. In women, RPP was positively associated with BMD at both sites in unadjusted models, and this association persisted at the lumbar spine after adjustment for covariates. No associations were observed between RPP and BMD in men. In women, PP was inversely associated with hip BMD in unadjusted models and positively associated with BMD at both sites after adjustment. In men, PP was negatively associated with total hip BMD when unadjusted, which attenuated after adjustment. PP was positively associated with spine BMD, before and after adjustment.
Conclusion
Cardiovascular risk factors are associated with BMD in adults. Associations are seen at the spine and hip in women, and at the spine only in men.