The Relationship of Serum Homocysteine Levels with Lumbar and Femoral Bone Mineral Density

BACKGROUND: Recently, an elevated serum homocysteine level has been reported to be associated with increased fracture risk and reduced bone mineral density (BMD). So far, little research has been done to evaluate such association in Korean population. Therefore, we investigated the association between serum homocysteine levels and BMD in Korean adults. METHODS: The subjects consisted of 2,750 adults who visited a health promotion center at a university hospital from January 2005 to March 2006. Self-administered questionnaires provided information about lifestyle and medical history. Fasting plasma samples were collected and BMD of the lumbar spine and femoral neck were obtained by dual energy X-ray absorptiometry. To adjust for menopausal state, the female subjects were divided into three groups according to age (< or =45 yrs, 46~55 yrs, 55 yrs <). Multiple linear regression analysis was used to evaluate the association between serum homocysteine levels and BMD in each gender and age group. RESULTS: The results adjusted for alcohol and smoking history showed significant association between serum homocysteine levels and BMD in women (Lumbar spine: beta=-0.006, P=0.015, Femoral neck: beta=-0.065, P=0.012) but not in men (Lumbar spine: beta=0.001, P=0.240, Femoral neck: beta=0.001, P=0.242). With analyses by three age groups, plasma homocysteine level was associated with both lumbar and femoral BMD in age 46~55 women (Lumbar spine: beta=-0.014, P=0.024, Femoral neck: beta= -0.007, P=0.019). CONCLUSION: Our study suggests that increased serum homocysteine level is an independent risk factor for low BMD among women, especially perimenopausal women. Further studies about the sexual differences and the mechanisms linking serum homocysteine level to BMD are needed.

Smoking Status and Augmentation Index in Korean Male Subjects

BACKGROUND: Smoking is a major risk factor of cardiovascular morbidity and mortality. Arterial stiffness has been identified as an important determinant of cardiovascular risk. Augmentation index is an indicator of arterial stiffness, which can be quantified noninvasively. The goal of this study was to assess the effect of current smoking status on augmentation index (AIx) in Korean male subjects. METHODS: A total of 70 males without clinical cardiovascular diseases were studied in this cross sectional study. AIx was measured in 35 current smokers and 35 nonsmokers by recording pressure waveforms using radial applanation tonometry in a SphygmoCor device. RESULTS: Augmentation index was significantly higher in the current smokers (19.4+/-12.9% vs. 9.7+/-12.8%; P<0.05). A multiple regression model confirmed that smoking status was independently associated with arterial stiffness (beta=0.350, P<0.001). CONCLUSION: Current smoking is associated with increased augmentation index, which is a marker of cardiovascular disease. Further studies are required to investigate clinical applications of arterial stiffness.