超音波檢查與亞太骨質疏鬆風險評估工具OSTA之比較研究－－以南臺灣某區域教學醫院體檢民眾

Comparison Study for Antitative Ultrasound Measurement and Osteoporosis Risk Assessment Tool OSTA-the People of Physical Examination in Southern Taiwan Regional Teaching Hospitals

本研究目的於南台灣某一區域教學醫院體檢民眾以超音波儀量測骨質密度（bone mineral density，BMD）與亞太骨質疏鬆風險評估工具（the Osteoporosis Self-assessment Tool for Asians , OSTA）作比較性研究。證實OSTA的適用性，期能早期採取預防行為以降低罹病率、死亡率及公共衛生資源。本研究受試者65533人，男性37506人，女性28027人。採用人體測量、OSTA及使用超音波儀執行腳後跟超音波測量。男性平均年齡為37.58±9.92歲，女性平均年齡為37.16±9.62歲。男性平均身體質量指數（body mass index ,BMI）為24.39±3.67，女性平均身體質量指數為22.62±3.91。超音波骨質密度分類結果顯示男性83.2%為低危險性，16.4%為中危險性，0.4%為高危險性。女性78.6%為低危險性，20.6%為中危險性，0.8%為高危險性。OSTA分類結果顯示男性96.8%為低危險性，3.0%為中危險性，0.2%為高危險性。女性87.5%為低危險性，11.5%為中危險性，1.0%為高危險性。OSTA鑑定男性敏感度（sensitivity）、特異性（specificity）、陽性預測值（positive predictive value）及陰性預測值（negative predictive value）為6.63%、97.45%、34.41%、83.83%。女性敏感度、特異性、陽性預測值及陰性預測值為26.39%、91.31%、45.18%、82.04%。本研究為了篩檢骨質疏鬆低危險患者而取OSTA值＞1 和超音波骨密度儀測量之T值＞-1.0屬於低危險的條件為標準來比較，獲得敏感度的範圍為6.63%~ 26.39%，特異性的範圍為91.31%～97.45%。結果不論男性或女性的特異性均大於90%，顯示OSTA和超音波骨密度儀在篩檢骨質疏鬆低危險群族上是有一致性。因此本研究認為OSTA在篩檢骨質疏鬆低危險群族是一件有效自我評估的工具，利用OSTA篩檢出低危險群的受檢者，再接受超音波骨密度儀檢測可能不是必需的。

This study was to explore the relationship between BMD measurements obtained by means of quantitative ultrasound on the right heel and means of the Risk Assessment tool OSTA-The People of Physical Examination in Southern Taiwan Regional Teaching Hospitals. The aim was to confirm the application of the OSTA to the population. It is expected to achieve early identification of individuals at greater risk of this disease. Preventive action to decrease morbidity and mortality of this disease should be used to decrease the public health resources.Sixty-five thousand and five hundred thirty-three people was included in this study. Those who took the examinations of anthropometric measurements, OSTA calculations and quantitative ultrasound on the right heel using CUBA equipment.The sample population was divided into 37506 men and 28027 women. The mean age among men population was 37.58±9.92, and the mean of body mass index was 24.39±3.67. The mean age among women population was 37.16±9.62, and the mean of body mass index was 22.62±3.91. The quantitative ultrasound classifications in men were 83.2 % in low-risk, 16.4 % in medium-risk, 0.4 % in high-risk, and in women were 78.6 % in low-risk, 20.6 % in medium-risk, 0.8 % in high-risk. The OSTA classifications in men were 96.8 % in low-risk, 3.0 % in medium-risk, 0.2% in high-risk and in women were 87.5 % in low-risk, 11.5 % in medium-risk, 1.0 % in high-risk. The sensitivity, specificity, negative predictive value and positive predictive value in men OSTA were 6.63 %, 97.45 %, 34.41 % and 83.83 % and in women were 26.39%, 91.31 %, 45.18 % and 82.04 %, respectively. The study showed that the specificity of OSTA in men and women were higher than 90%.Based on the datum comparisons of OSTA value ＞ 1 and the gold standard （ultrasound T score ＞ -1.0） among the study population, the sensitivity of OSTA evaluation was 6.63%~ 26.39 % and the specificity was 91.31%~ 97.45 %. Among the low risk population of osteoporosis, the specificity was consistently higher than 90% in gender population. The study showed that OSTA was a valid tool for osteoporosis screening specially for people in low risk in the southern Taiwan. Therefore, those who had a low risk osteoporosis evaluation by OSTA might not need to take extra ultrasound examinations.