In a 1994-1995 cross-sectional, population-based study of 2,543 men and 2,726 postmenopausal women aged 55-74 years in Tromsø, Norway, the authors assessed a possible relation between bone mineral density (BMD) and the prevalence of carotid artery plaques, with an emphasis on plaque morphology. BMD measurements of the forearm and ultrasonography of the carotid artery were performed. Study participants were divided into quartiles with respect to sex-specific BMD values. Prevalent plaques were categorized into four groups ranging from low echogenicity to high echogenicity. For echogenic plaques, a significant inverse correlation with BMD was found (p for linear trend=0.007 after adjustment for age, sex, and cardiovascular risk factors). For predominantly echogenic plaques, a similar but weaker association was indicated (p = 0.08); for predominantly echolucent and echolucent plaques, no significant associations were observed (p > or = 0.3). Subjects whose BMD values were in the highest quartile had a statistically significant lower risk of echogenic plaques than subjects whose BMD values were in the lowest quartile (odds ratio=0.51, 95% confidence interval: 0.31, 0.83). This study indicates that low bone mass is associated with an increased risk of echogenic calcified atherosclerotic plaques but not with a risk of echolucent plaques.