【ElsevierMed】不同類型的嬰兒配方奶可能影響1型糖尿病發病風險
據11月11日發表於《新英格蘭醫學雜誌》(the New England Journal of Medicine)的一項研究，對於1型糖尿病發病風險較高的兒童而言，如果在嬰兒期食用水解酪蛋白含量較高的配方奶，則其隨後出現β細胞自身免疫性損傷相關體征的幾率會較低(相較於以牛奶為主要成分的配方奶)，且該優勢一直持續到患兒10歲時。
這項研究為一項名為TRIGR[旨在降低胰島素依賴型糖尿病(IDDM)遺傳學發病風險的試驗]的初步研究，共納入230例於1995~1997年間出生于芬蘭境內15所醫院的新生兒，人類白細胞抗原(HLA)基因分型顯示這些新生兒易患1型糖尿病，且這些新生兒至少有一位一級親屬也患有此疾病。所有新生兒均按隨機雙盲模式分配至干預組[食用水解酪蛋白含量較高的配方奶(Nutramigen)]或對照組(食用以牛奶為主要成分的配方奶，但經處理後氣味和味道均非常近似於前者)組，餵養共持續6個月。研究鼓勵母乳餵養，僅在母乳不足時才會使用配方奶餵養嬰兒，但允許母親自行決定何時哺乳，母親的飲食也未受干涉。研究對所有受試者血樣中的5種疾病相關性自身免疫性抗體進行了週期性檢測：胰島細胞抗體；胰島素抗體；谷氨酸脫羧酶抗體；酪氨酸磷酸酶相關性-胰島素瘤相關蛋白2(IA-2)抗體和鋅轉運體8(ZnT8)抗體。
結果顯示，干預組患兒血清中胰島細胞抗體、IA-2自身免疫性抗體(或是5種受檢抗體中的任意一種)呈陽性的幾率顯著降低(N. Engl. J. Med. 2010;363:1900-8)；在患兒10歲時，干預組和對照組分別有6%和8%的受試者罹患1型糖尿病，該差異無顯著性，但發病率不是本研究的主要研究指標。
既往小規模臨床研究和動物實驗的初步資料均表明，在哺乳期食用成分複雜的外源性蛋白飲食會增高自身免疫性糖尿病的發病風險，但確切機制尚不清楚。本研究首次表明，水解蛋白含量較高的配方奶可用于預防高危兒童罹患1型糖尿病。鑒於新診斷的1型糖尿病患兒中有83%~98%來自于一般人群，如果該論點得到確證(本研究因檢驗效能不足尚無法得出確定結論)，就應該在普通嬰兒群體中將這一干預模式作為一項公共衛生政策加以推廣。
本研究由芬蘭科學院、歐盟委員會、國際青少年糖尿病基金會、諾和諾德基金會及數項非企業來源經費聯合資助。嬰兒配方奶由美贊臣營養公司提供，但該公司未參與本研究的試驗設計，資料收集和分析及論文撰寫過程。一位作者表示接受過兒科研究基金會的經費支援，其餘作者無利益衝突披露。
1型糖尿病及其飲食誘因
本研究的主要發現是：在食用水解酪蛋白配方奶的兒童中，血清學檢測發現至少1種自身免疫性抗體呈陽性的受試者比例為17%，相比之下，對照組患兒的這一比例為30%。但2組兒童最終罹患糖尿病的百分比十分接近。
曼徹斯特大學的Harlan博士和Lee博士表示，該實驗設計中的某些不定因素可能導致結果失真：首先，對照組嬰兒接受配方奶的中位年齡(1.1個月)顯著早于干預組嬰兒(2.6個月) (N. Engl. J. Med. 2010;363:1961-3);其次，干預組最終罹患1型糖尿病的7例患兒中有3例在尚未開始食用配方奶時便已退出研究，他們的自身免疫性抗體檢查結果極有可能也是陽性(實際並未檢查)，這會顯著抵消2組受試者在自身免疫性抗體血清陽性率這一指標上的差異。
Harlan博士表示與美國糖尿病協會存在聯繫，Lee博士表示與Tolerx公司、Diamyd公司和百特公司存在聯繫。
2010-11-12
來源:
http://hi.baidu.com/ielsevier/blog/item/beae496687a62ce0f636545b.html
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PITTSBURGH (KDKA) — Type I diabetes typically strikes in childhood and requires careful monitoring with finger sticks and insulin injections.
Local researchers are hoping to be able to prevent the condition with diet.
Can feeding a baby a special formula cut the risk of Type I diabetes?
“My initial reaction was disbelief,” says Children’s Hospital endocrinologist Dr. Dorothy Becker.
The idea came from studies in mice. They were less likely to have the condition if given a special type of formula.
“The suggestion came that it’s got nothing to do with the fact that’s it’s milk, but it’s probably an intact foreign protein that’s different from mother’s milk that may be important in susceptible babies,” Dr. Becker explains. “It was decided to do a pilot study in Finland which has the highest incidence of Type I diabetes in the world.”
A “New England Journal of Medicine” study looked at 230 infants — half were fed regular and half were fed a special formula. In the specially-prepared version, the proteins in standard cow milk formula were pulverized into teeny tiny particles – too small to activate the immune system. With Type I diabetes, the condition is related to an autoimmune attack against the cells in the pancreas that make insulin.
The study was too small to know if this actually reduced the risk of developing diabetes, but the babies fed regular cow milk were twice as likely to develop diabetes-related antibodies anywhere from age three months to 10 years.
A much larger ongoing study of more than 2,000 babies across 15 countries is expected to give more conclusive results. Children’s Hospital is part of that study.
“It is the first trial ever to start in the newborn period,” says Dr. Becker. “Now our biggest challenge is keeping contact with everybody in the study.”
Sixty-eight local families are participating. The children will be followed to age 10. The results are expected in 2017.
“That’s always frustrating, yes,” Dr. Becker concedes, who has been involved with studies on the subject for nearly two decades already. “I will be older when we get the answer, but I’m going to hang in there.”
Studies have focused on people with a susceptible genetic make up, but 90 percent of people with Type I diabetes do not have a family history. For that reason, Dr. Becker expects that if the larger study mirrors the pilot study, the findings could apply to the general population.
But the expense of specially-treating formula proteins may be a hard sell to manufacturers.
來源:
http://pittsburgh.cbslocal.com/2010/11/11/infant-formula-could-play-role-in-type-i-diabetes/
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