Little is known of the relationship between bone mass and parameters of vascular health. Intima-media thickness (IMT) is an important atherosclerotic risk marker and associations between carotid IMT and bone mass have been observed in postmenopausal women. Differences in IMT, however, are yet to be demonstrated between post-menopausal women with and without osteoporosis. Furthermore, a preliminary study reported relationships between poor bone mass and increased blood viscosity; however, that study was conducted in rats.
Aim: To compare IMT and blood viscosity of post-menopausal women classified as either normal, osteopenic, or osteoporotic on the basis of BMD T-score criteria.
Methods: We recruited 70 apparently healthy post-menopausal women (age 64.9 ±5.8 years). Whole body BMD was measured by DXA and T-scores were used to separate participants into healthy (T-score above -1 SD), osteopenic (T-score between -1 and -2.5 SD) and osteoporotic (T-score below -2.5 SD) groups. IMT of the carotid and femoral arteries was determined by two-dimensional B-mode ultrasound using a 10 MHz linear transducer and edge-detection software. Blood was drawn from the antecubital vein and blood viscosity was determined using a rotational cone-plate viscometer. Differences in IMT and blood viscosity between groups were examined with one-way ANOVA, while associations were investigated with Pearson correlations.
Results: Carotid IMT of women with osteoporosis (0.968 ±0.267 mm) was greater than that for women with osteopenia (0.672 ±0.196 mm) or normal BMD (0.659 ±0.198 mm) (p = 0.019). No differences existed between BMD T-score groups for femoral IMT or measures of blood viscosity. No significant associations were observed between measures of IMT or blood viscosity and bone mass at any site (p > 0.05).
Conclusion: Abnormally high carotid IMT values were observed in women with osteoporosis compared to women without, which may be indicative of co-morbid vascular impairment in this population.