由於現代人生活及飲食習慣的改變，影響國民健康狀態，增加罹患心血管疾病機會，其中動脈硬化常被視為引發心血管疾病之重要危險因子之一，因此如何早期預估動脈硬化，對於預防心血管疾病將是一個重要的議題，本研究之目的在於應用量測光學體積測量法，經由指尖末稍血流波形變化，擷取各種相關參數加以分析比較，以便估測血管年齡。本研究量測30位不同年齡之無診斷性心血管疾病受試者，從光學體積變化波形總計擷取九個參數，並以佛明罕心臟研究之心血管估測為參考標準，從實驗結果顯示，受試者血管年齡與前述五項參數有顯著相關性，其中SI，∆P1和∆t4三個參數與血管年齡成正相關，而b/a ratio and PPT兩個參數隨血管年齡增加而降低；故本研究所提出之參數可以簡單有效作為估測血管老化。

Due to the changes of living and dietary habits, the health of people is significantly affected. The prevalence of cardiovascular disease is increased. The arterial stiffness is usually regarded as the risk factor of acquiring the cardiovascular disease. Therefore, how to estimate the vascular status is an important issue in cardiovascular disease prevention. This purpose of this study is to apply the bilateral photoplethysmography (PPG) system to measure the blood flow waveform from the figure tips, and then to extract and compare the associated parameters for estimate the vascular age. 30 subjects without history of cardiovascular disease are recruited in this study. From the experimental results, five parameters show their good correlation with the vascular age obtained from Framingham Heart Study. Three parameters such as SI, ∆P1, and ∆t4 are increased in proportion with the vascular age. The other two parameters such as b/a ratio and PPT are decreased with vascular age. These parameters obtained from this study are demonstrated to be easy and useful in the estimation of vascular aging.

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