ビスフォスフォネートによる骨吸収マーカーの変動―アレンドロネートとリセドロネートの比較

Changes in Bone Resorption Marker with Alendronate and Risedronate

　アレンドロネートまたはリセドロネートの投与後の骨吸収マーカー（尿NTX）の変動について検討した．投与1カ月後と6カ月後の尿NTX低下率は，アレンドロネートが大きい傾向にあったものの両群間に有意差は認めなかった．骨折高リスク症例（NTX初期値：54.3以上）では，1カ月後ではアレンドロネートの低下率が有意に大きかったが，6カ月後には両群間に有意差は認められなかった．また，最小有意変化（35％以上の低下）を示した症例の割合では両群に有意差は認められなかったことから，両者の有効性に差はないことが推察された．

　Changes in a bone resorption marker (urine type Ⅰ collagen crosslinked N-telopeptide, NTX) were evaluated after the administration of alendronate or risedronate. Alendronate produced a greater reduction in NTX than risedronate after one and six months of administration, but these changes were not significant. In a high-risk fracture group (NTX≥54.3), alendronate produced a significant decrease in NTX after one month of administration, compared to risedronate, but no significant change was observed after six months of administration. No significant differences in the percentage of cases with minimum significant changes (decreases of more than 35％) were observed between the alendronate and risedronate groups, indicating that both bisphosphonates might have a similar efficacy.