以手臂動脈硬度指數評估無症狀接受健康檢查者之心血管病風險

Brachial Arterial Stiffness Index as a Cardiovascular Risk Marker in Asymptomatic Individuals

過去的研究已知手臂動脈硬度指數（arterial stiffness index; ASI）可反映動脈血管硬度，因此被建議使用於心血管病風險的評估。但針對外表健康的無症狀族群，使用手臂動脈硬度指數來評估心血管病風險的研究則不多。本研究之目的即在探討以手臂動脈硬度指數預測此一族群未來發生心血管病風險的能力，本研究同時探討手臂動脈硬度指數與各種心血管病危險因子間的關聯性與影響測定手臂動脈硬度指數的因素。本研究選取316位（男性176位，女性140位，平均年齡48±11歲）自願來院做健康檢查的人士分析，這些參加者皆外觀正常且無臨床症狀。本研究詳細記錄其血壓、身高、體重、家族病史、各種心血管病危險因子、抽血測定血脂肪、血脂蛋白及空腹血糖、並使用CardioVision MS-2000型機器測量其手臂動脈硬度指數。最後吾人使用Framingham心血管病風險評估計分表來計算每人未來十年發生心血管病的風險，並統計分析手臂動脈硬度指數是否能預測此風險。本研究發現手臂動脈硬度指數與心血管病危險因子，包括：年齡、血壓、總膽固醇、低密度脂蛋白膽固醇、三酸甘油酯及脈搏速率等之間確有顯著之相關性。多變項分析則顯示影響手臂動脈硬度指數之測量值的主要決定因素是年齡及血壓數值。手臂動脈硬度指數與參加者依Framingham心血管病風險評估表計算所得的分數間成明顯正相關（r ＝0.324, p <0.0001）。吾人進一步將參加者依換算所得的十年內心血管病風險分為低風險組（其十年內心血管病風險≤10%）及中等風險組（其十年內心血管病風險>10%），結果前組之手臂動脈硬度指數數值明顯低於後組（50±18 vs. 58±21, p=0.001）。以非侵入方式測量手臂動脈硬度指數應有助於評估此族群將來發生心血管病之風險，惟仍須進一步以大規模前瞻性的研究來證實。

Previous studies have shown that arterial stiffness, when determined invasively, is known to be a major contributor to atherosclerosis and one of the most important causes of cardiovascular disease (CVD). The aim of this study is to assess the feasibility of the arterial stiffness index (ASI) using a non-invasive computerized oscillometric device (Cardio Vision, MS-2000) and the predictive value of ASI for CVD risk level in asymptomatic individuals, and to seek cardiovascular risk factors influencing ASI. In this study, ASI was obtained using the Cardio Vision MS-2000 instrument in 316 asymptomatic, apparently healthy subjects (M/F=176/140; aged 48±11 years) who were admitted for routine physical check-ups. Family history, serum lipids and lipoproteins, glucose levels and mercury sphygmomanometer blood pressure measurements were collected. The risk for CVD in each individual was assessed by the Framingham Risk Score System. Results: Significant correlations were found between ASI and various risk factors, including age, measures of blood pressure, total cholesterol, low-density-lipoprotein cholesterol, triglyceride, and pulse rate. The multivariate regression analyses showed that age and blood pressure independently predict changes in ASI. Furthermore, ASI was significantly positively correlated with Framingham Risk Scores (r=0.324, p＜0.0001). Subjects with a 10-year risk for a future CVD events of≤10% have significantly lower ASI than those whose risk for CVD are ＞10% (50±18 vs. 58±21, p=0.001). Our findings suggest that noninvasive measures of ASI are effective in assessing cardiovascular risk. Further and larger prospective studies are still necessary, to determine whether they may provide clinicians and research scientists with another diagnostic tool in addition to standard CVD risk factors.