CHRONOLOGICAL CHANGES IN BONE-MINERAL CONTENT FOLLOWING GASTRECTOMY

Recent advances in the modalities of quantitatively assessing bone min eral content have resulted in an increasing awareness of metabolic bon e disease as a late complication following gastrectomy. In this study, 98 postgastrectomy patients were examined by quantitative computed to mography (QCT). The bone mineral density index (BMDI), defined as 100 X (measured bone mineral density divided by that of age and sex-matche d controls), was used to evaluate the actual effect of gastrectomy on bone disorders. The BMDI values following gastrectomy were 80.4 +/- 27 .3, with no significant difference between men and women, or between t otal and distal gastrectomy. Moreover, no significant differences were observed between the BMDI values within 6 months, being 92.6 +/- 37.3 , and those 6 months to 1 year post gastrectomy, being 79.6 +/- 31.2; however, a significant and sharp decrease to 70.5 +/- 36.0 was evident after 1-2 years. The regression coefficient of the BMDI measured with in 2 years postoperatively was lower than that measured after 2 years. These findings suggest that the influence of gastrectomy on bone meta bolism is induced within 2 years, after which the bone mineral content decreases in accordance with physiological nature. Thus, we conclude that the treatment for bone disease resulting from gastrectomy would o nly be effective if initiated within a short period after surgery.