中老年人抗氧化營養素濃度與體組成及肌力適能相關性之探討

老化相關之氧化壓力可能導致肌肉質量及肌力適能下降使得中老年人為易罹患肌少症之族群，抗氧化營養素具有平衡氧化壓力造成損傷之特性，本研究目的為了解中老年人之抗氧化營養素（輔酶Q10、β-胡蘿蔔素、維生素A及維生素E）濃度與其體組成及肌力適能之相關性。本研究為一橫斷面研究，招募年齡40-85歲之中老年人為研究對象。測量研究對象之體位資料，利用雙能量X光吸收儀測定體組成，並以握力計、手臂啞鈴彎舉、背筋力計、30秒坐姿起立、6分鐘步行及簡短身體功能量表評估其肌力適能。採集血液檢體測量血液生化值及分析抗氧化營養素（輔酶Q10、β-胡蘿蔔素、維生素A及維生素E）濃度。本研究共招募100名研究對象，結果發現其中有16%研究對象罹患肌少症，有接近六成研究對象輔酶Q10缺乏，而β-胡蘿蔔素、維生素A及維生素E缺乏比例則小於10%。經年齡分組後，65歲以上老年研究對象之肌肉質量（包含全身、軀幹及四肢）、全身及四肢肌肉質量指數顯著低於40-64歲中年研究對象（p < 0.05），且老年研究對象之肌力適能（包含握力、手臂啞鈴彎舉、背筋力計、30秒坐姿起立、步行速率及簡短身體功能量分數）亦顯著低於中年研究對象（p < 0.05）。此外，研究對象血漿輔酶Q10/總膽固醇 ≥ 0.1 μmol/mmol有顯著較高的軀幹肌肉量（p = 0.04）及全身肌肉質量指數（p = 0.02）。以複迴歸分析發現，輔酶Q10/總膽固醇濃度與軀幹肌肉質量、全身肌肉質量指數、啞鈴彎舉、背筋力計、30秒坐姿起立及簡短身體功能量表分數呈顯著之正相關（p < 0.05）；經性別及年齡調整後，輔酶Q10/總膽固醇濃度仍與全身肌肉質量指數（p = 0.08）、30秒坐姿起立（p = 0.03）及簡短身體功能量表分數（p = 0.02）呈顯著正相關。由以上結果推論，超過半數的中老年人處於較低之輔酶Q10濃度狀態，且其輔酶Q10濃度與肌肉質量及肌力適能呈顯著之正相關性，故我們建議中老年人應監測輔酶Q10營養狀態，因其可能會進一步影響肌肉質量及肌力適能之表現。

Age-related oxidative stress may lead to loss of muscle mass and strength, and susceptible to sarcopenia in a middle-aged and elderly population. Antioxidant nutrients play a role in balancing oxidative stress damage from aging. The aim of this study was to investigate the relationship between antioxidant nutrients (coenzyme Q10, β-carotene, vitamin A and vitamin E) and body composition, muscle strength and endurance in middle-aged and elderly adults. This was a cross-sectional study. We recruited middle-aged and elderly subjects who aged 40-85 years. The body composition was assessed by dual-energy X-ray absorptiometry. The muscle strength and endurance was evaluated by grip strength dynamometer, dumbbell curl, back dynamometer, 30-second chair stand test, six-minute walk test and short physical performance battery (SPPB). Fasting blood sample was collected to measure the levels of hematological data, coenzyme Q10, β-carotene, vitamin A and vitamin E. One hundred subjects were enrolled in the present study and the results showed that 16% of subjects suffered from sarcopenia. With regard to antioxidant nutrients status, almost 60% of subjects had coenzyme Q10 deficiency and less than 10% of the subjects had β-carotene, vitamin A or vitamin E deficiency. The elderly subjects showed significantly lower muscle mass and strength compared with the middle-aged subjects (p < 0.05). Subjects with a higher level of coenzyme Q10/total cholesterol (≥ 0.1 μmol/mmol) had significantly higher trunk muscle mass (p = 0.04) and whole-body muscle mass index (p = 0.02). In addition, the level of coenzyme Q10/total cholesterol concentration was significantly positively correlated with trunk muscle mass, whole-body muscle mass index, dumbbell curl, back dynamometer, 30-second chair stand test and SPPB (p < 0.05). After adjusting for sex and age, the level of coenzyme Q10/total cholesterol concentration still significantly positively correlated with whole-body muscle mass index (p = 0.08) and 30-second chair stand test (p = 0.03) and SPPB (p = 0.02). In conclusion, more than half of the middle-aged and elderly adults had coenzyme Q10 deficiency. Since the level of coenzyme Q10 was positively correlated with muscle mass and strength, we suggested that the middle-aged and elderly adults should monitor their coenzyme Q10 status which may further affect the muscle mass and muscle strength and endurance.