Normal bone mineral density in anteroposterior, lateral spine and hip of Chinese men in Taiwan: effect of age change, body weight and height.

BACKGROUND: The purpose of this study was to establish complete normative bone mineral density (BMD) values of Taiwanese men for anteroposterior, lateral spine, and hip. METHODS: Five-hundred and 69 healthy men (aged 20 to 88 years) were recruited to establish normal reference data of lumbar spine and hip, measured by a Hologic QDR 2000 bone densitometer. One-way analysis of variance was used to examine mean difference of BMD between different age groups. The effect of age change, body weight and height on BMD was determined by multivariate linear regression. RESULTS: The peak BMD values of most anatomic sites occurred in the age 20-30 group, and were 1.017, 0.862, 0.909, 0.860, 0.993 g/cm2 for anteroposterior spine, lateral spine, femoral neck, Ward's triangle, and total hip, respectively. The BMD values then steadily decreased with increase of age. After age 60-70, there was less age-related reduction of BMD values at the anteroposterior, lateral spines and Ward's triangle. By the 8th decade, the percentage losses in the anteroposterior spine, lateral spine, femoral neck, Ward's triangle, and total hip were 12%, 22%, 30%, 45%, and 22%, respectively. The BMD values correlated better with age and body weight than with body height at all anatomic sites. The body height was insignificant in predicting the BMD values at most anatomic sites. As compared with the normative BMD value provided by the Hologic Corporation, Chinese men had lower BMD value than Caucasian at most sites except Ward's triangle. At the anteroposterior spine, the values of Chinese and Japanese men were similar, whereas at the hip and its subregions, Chinese young male population had higher bone mineral density than Japanese. CONCLUSIONS: The data provided by this study may be used as normal reference values for Taiwanese men, instead of the values for Asians provided by the manufacturer.

Metallic stenting for treatment of central venous obstruction in hemodialysis patients.

BACKGROUND: Central venous obstruction is a serious and common complication in hemodialysis patients. The recurrence rate is high after balloon dilation, while surgical repair is hazardous in these chronically ill patients. The aim of this study was to evaluate the efficacy of primary Wallstent placement for treatment of hemodialysis-related central venous obstructions. METHODS: Eighteen hemodialysis patients with symptomatic shunt dysfunction and arm swelling due to subclavian (n = 3) or innominate (n = 15) venous obstructions were treated at Kaohsiung Veterans General Hospital with primary Wallstent placement from November 1998 to August 2001. Technical success and complications were reported. Primary and secondary patency rates of stent and hemodialysis access were calculated by survival analysis with Kaplan-Meier method. RESULTS: A total of twenty-five Wallstents were deployed for central venous stenosis (n = 18) and occlusion (n = 7) in these 18 hemodialysis patients. The initial technical success rate was 100%. Fourteen episodes of re-obstruction developed during the observation period. Of them, seven episodes occurred within the stent, four episodes outside of but abutting to the peripheral end of the stent, and another three episodes of re-obstruction were attributed to delayed shortening of the Wallstent. Six of the 14 episodes were treated percutaneously with angioplasty alone, while seven episodes necessitated additional stent placement. No stent migration or other complications were encountered. Primary patency rates of stent and hemodialysis access at 3, 6, 12 and 18 months were 100 and 89%, 73 and 68%, 49 and 42%, and 16 and 0%, respectively. Secondary patency rates of stent and hemodialysis access each were both 100% after 3 months, 93 and 100% after 6 months, 85 and 91% after 12 months and, 68 and 72% after 24 months. CONCLUSIONS: Wallstents are safe to deploy, with excellent technical success for hemodialysis-related central venous obstructions. The Wallstent provides continued use of a hemodialysis access for a substantial period. However, repeated interventions may be necessary to maintain the patency.