F Mohseni, MR Mohajeri-Tehrani, B Larijani, Z Hamidi

Abstract

Purpose: Chronological and longitudinal changes of bone density in patients with secondary osteoporosis, have been shown helpful in providing a model of calcium and bone metabolism. This model can be used in the understanding and management of bone disorders in primary osteoporosis. Objective: The aim of our study was to investigate bone density changes in thalassemic patients. Method: Thalassaemic patients from 7-33 y/o were included in this study. Sixty-five bone mineral density (BMD) scans were collected (21 scan related to paediatric patients (<20 y/o) and others related to adults). BMDs were repeated one year later in all patients. A Norland XR-46 device was used for BMD measurement. Results: There was no case of "low bone density for chronologic age (Z-score ≤-2)" in children. "Z-score ≤-2" was found in 53.4% (23 cases) of adult patients, respectively. The odds of Z-score ≤-2 in patients at age 21 y/o and older, in femoral region were 13.12 times greater than for younger patients (CI=1.596-107.962, P-value=0.017). The odds of Z-score ≤-2 in patients at age 22 y/o and older, in femoral region were 8 times greater than for younger patients (CI=1.626-39.354, P-value=0.011). BMD changes in spinal and femoral regions, were not different significantly in various age groups of patients. Conclusion: As thalassaemic patients got older, though their absolute BMD increases, but in comparison to their age and sex matched controls, it decreases and their delay in acquiring peak bone mass is clear.

目的：繼發性骨質疏鬆患者的時間及縱向骨密度變化已被證實能夠幫助建立鈣以及骨代謝模型。該模型可用於加強對原發性骨質疏鬆中骨病變的認識及控制。該研究目的是探究地中海貧血患者骨密度變化情況。方法：7~33歲的地中海貧血患者被納入該研究中。我們收集了65次骨鹽密度（BMD）掃描結果，其中21次掃描是針對小兒患者（小於20歲）而其餘為成人。一年後所有患者再進行一次BMDs。掃描中使用了Norland XR-46進行BMD測量。結果：兒童中無一病例顯示「隨年齡發生的低骨密度（Z-評分≤-2）」，而在成人中該情況的發生率為53.4%（23例）。21歲及以上患者Z-評分≤-2的機率為20歲及以下患者的13.12倍（CI=1.596-107.962, P-value=0.017）。而22歲以上患者Z-評分≤2的機率則為21歲及以下患者的8倍（CI=1.626 - 39.354, P-value = 0.011）。在各年齡段脊椎和股骨區的BMD改變沒有顯示出統計學意義上的差別。結論：當地中海貧血患者年齡增長時，雖然其絕對BMD有所上升，但與同年齡性別對照組比較時，表現出相對BMD下降及峰值骨品質需求呈現延遲。