健康與患有慢性病的老年人其維生素B-6的攝取及營養狀況的評估

研究指出隨著年齡的增長可能會有維生素B-6營養狀況的下降的情形。本篇研究的主要目的在調查老年人（65歲）的維生素B-6攝取及評估其營養狀況。94位受試者依性別及是否患有慢性病被分為4組（28位健康男性、11位患慢性病男性、29位健康女性、26位患慢性病女性）。營養素攝取是以24小時飲食回憶法及食物頻率問卷分析。維生素B-6營養狀況是以血漿磷酸比哆醛（pyridoxal 5’-phosphate；PLP）及比哆醛（pyridoxal；PL）、紅血球丙胺酸轉胺活性係數（EALT-AC）及紅血球天門冬胺酸轉胺活性係數（EAST-AC）作為評估的指標。結果顯示所有組別的平均維生素B-6攝取量均高於目前台灣老年人的維生素B-6建議攝取量（男性，1.6 mg/d；女性，1.4 mg/d）。相同性別（男性及女性）的健康及患慢性病組的血漿磷酸比哆醛和紅血球丙胺酸轉胺活性係數及紅血球天門冬胺酸轉胺活性係數並無顯著差異。另外也發現性別、健康狀況對維生素B-6攝取、血漿磷酸比哆醛、血漿比哆醛、紅血球丙胺酸轉胺活性係數並無任何影響。但是健康老年人比患慢性病老年人有較缺乏的紅血球天門冬胺酸轉胺活性係數（p = 0.0134）。健康男性（r = -0.48，p ＜0.05）及所有受試者（r = -0.21，p ＜0.05）的維生素B-6攝取量與紅血球天門冬胺酸轉胺活性係數呈顯著負相關。回歸分析指出將紅血球天門冬胺酸轉胺活性係數回復到建議指標（＜1.8）需要至少攝取2.34 mg/d的維生素B-6。雖然老年人有足夠的維生素B-6攝取量，但維生素B-6的代謝及利用可能因其他原因而受到限制。最後建議老年人增加維生素B-6的攝取量或許有助於改善維生素B-6的營養狀況。

The purpose of this study was to assess vitamin B-6 intakes and status in healthy elderly and elderly with chronic diseases. Subjects were divided into 4 groups ( 28 healthy males, 11 males with chronic diseases, 29 healthy females, 26 females with chronic diseases). Each subjects completed a 24-h diet recall and food frequency questionnaire. Plasma pyridoxal 5’-phosphate (PLP) and pyridoxal (PL), erythrocyte alanine and aspartate aminotransferase activity coefficients (EALT-AC and EAST-AC) were measured. The mean total vitamin B-6 intake (B-6 supplementation was included) was higher than the 1998 US Dietary Reference Intakes (DRI) and current Taiwan Recommended Daily Nutrient Allowance (RDNA) in all groups. Vitamin B-6 intake only correlated with EAST-AC in the healthy males (r=-0.48, p<0.05) and the pooled (r=-0.21, p<0.05) groups. There were no significant differences in plasma PLP, EALT-AC, and EAST-AC between healthy and chronically-disease groups. Only healthy elderly women had mean plasma PLP concentration equal to the suggested value (>30 nmol/L). There was no effect of sex or healthy status on vitamin B-6 intake, plasma PLP and PL, and EALT-AC. Healthy subjects tended to have abnormal EAST-AC values (p=0.0134) than subjects with chronic diseases. Regression analyses indicated that the amount of B-6 required to normalize EAST-AC to the suggested value (1.8) is 2.34 mg. The high incidence of biochemical vitamin B-6 deficiency in our elderly appears more related to an altered metabolism of vitamin B-6 than to the dietary intake of protein and vitamin B-6, healthy status or sex. Elderly subjects who increase their B-6 intake from food or supplementation might improve their vitamin B-6 status.