鐘冬賜 詹思延
[摘要] 目的 系統(tǒng)評(píng)價(jià)國內(nèi)外采用生酮飲食治療糖尿病患者的效果,從而更好地為糖尿病患者的飲食管理和綜合治療提供循證依據(jù)。 方法 通過檢索PubMed、Cochrane Library、EMbase、Sinomed、萬方醫(yī)學(xué)網(wǎng)、維普網(wǎng)等數(shù)據(jù)庫,收集國內(nèi)外對(duì)糖尿病患者使用生酮飲食治療的隨機(jī)對(duì)照試驗(yàn)(RCT),試驗(yàn)組給予低碳生酮飲食,對(duì)照組給予低卡路里食物或者平板健康餐,對(duì)所納入的文獻(xiàn)采用Jadad評(píng)分進(jìn)行質(zhì)量評(píng)價(jià),使用Review Manager5.3軟件進(jìn)行Meta分析。將試驗(yàn)組和對(duì)照組的糖化血紅蛋白含量、體重、甘油三酯水平等結(jié)局指標(biāo)進(jìn)行比較。 結(jié)果 該次Meta分析共納入文獻(xiàn)7篇,其中試驗(yàn)組200例病例,對(duì)照組155例病例。Meta分析結(jié)果顯示,試驗(yàn)組糖化血紅蛋白含量低于對(duì)照組[MD=-0.50,95%CI(-0.70,-0.30),P<0.01];試驗(yàn)組體重低于對(duì)照組[MD=-8.07,95%CI(-10.73,-5.40),P<0.01];試驗(yàn)組甘油三酯水平低于對(duì)照組[MD=-29.05,95%CI(-45.50,-12.71),P<0.01]。 結(jié)論 生酮飲食是一種能夠有效降低糖尿病患者糖化血紅蛋白含量,減輕體重,降低甘油三酯水平的膳食療法。
[關(guān)鍵詞] 糖尿病;生酮飲食;Meta分析
[中圖分類號(hào)] R587.2? ? ? ? ? [文獻(xiàn)標(biāo)識(shí)碼] A? ? ? ? ? [文章編號(hào)] 1672-4062(2020)01(b)-0032-05
[Abstract] Objective To systematically evaluate the efficacy of ketogenic diet in the treatment of diabetic patients at home and abroad, so as to provide evidence-based evidence for dietary management and comprehensive treatment of diabetic patients. Methods A randomized controlled trial (RCT) of ketogenic diet for diabetic patients was collected by searching PubMed, Cochrane Library, EMbase, Sinomed, Wanfang Medical Network, and VIP. The trial group was given a low-carbon ketogenic diet. The control group was given low-calorie food or flat-table healthy meal, and the included literature was evaluated by Jadad score, and the review was performed using Review Manager5.3 software. The outcome measures such as glycated hemoglobin content, body weight, and triglyceride levels in the test group and the control group were compared. Results A total of 7 articles were included in the meta-analysis, including 200 cases in the experimental group and 155 cases in the control group. Meta-analysis showed that the glycated hemoglobin content of the experimental group was lower than that of the control group [MD=-0.50, 95% CI(-0.70, -0.30), P<0.01]; the weight of the experimental group was lower than that of the control group [MD=-8.07, 95 %CI(-10.73,-5.40), P<0.01]; the triglyceride level in the test group was lower than that in the control group [MD=-29.05, 95% CI(-45.50, -12.71), P<0.01]. Conclusion ketogenic diet is a dietary therapy that can effectively reduce glycated hemoglobin levels, reduce body weight, and lower triglyceride levels in diabetic patients.
[Key words] Diabetes; Ketone diet; Meta-analysis
糖尿病作為一組以高血糖為特征的代謝性疾病,現(xiàn)在已經(jīng)逐漸發(fā)展成為全球三大導(dǎo)致過早死亡的健康危害因素之一[1]。糖尿病的發(fā)病原因和發(fā)生機(jī)制較為復(fù)雜,其并發(fā)癥較多,且后果較為嚴(yán)重[2-3],因此糖尿病患者非常需要早期治療和早期干預(yù)?,F(xiàn)在糖尿病的治療方式包括藥物治療、運(yùn)動(dòng)治療、生活方式干預(yù)、飲食治療等。盡管今年來在藥物治療方面取得了較大的進(jìn)展,藥物的不良反應(yīng)和潛在危害仍然使得人們對(duì)藥物治療的安全性保持很大的警惕。非藥物治療方案也逐漸受到人們的歡迎,比如采用低碳水化合物、高脂肪、適量蛋白質(zhì)組成的生酮飲食(ketogenic diet)治療。生酮飲食作為難治性癲癇[4-5](refractory epilepsy,RE)疾病的非藥物治療方式之一,已有近百年的應(yīng)用歷史。近年來,生酮飲食[6]開始被嘗試著用于糖尿病患者的治療,取得了一定的治療效果。目前大部分研究指出,生酮飲食能夠有效地降低糖尿病患者的糖化血紅蛋白含量,減輕他們的體重,降低其甘油三酯水平[7]。但是各個(gè)研究的樣本量都相對(duì)較小,試驗(yàn)結(jié)果的可信度不夠高。因此,該研究擬采用Meta分析的方法,系統(tǒng)評(píng)價(jià)入選的幾篇隨機(jī)對(duì)照試驗(yàn)研究,研究糖尿病患者采用生酮飲食治療的效果,為糖尿病的非藥物療法提供新的科學(xué)依據(jù)。
1? 方法
1.1? 文獻(xiàn)納入標(biāo)準(zhǔn)
①包含結(jié)局指標(biāo):糖化血紅蛋白(glycosylated hem- oglobin content,HbA1c);體重(weight);甘油三酯水平(triglyceride levels);②各納入文獻(xiàn)為RCT研究;③試驗(yàn)組和對(duì)照組資料具有可比性;
1.2? 文獻(xiàn)排除標(biāo)準(zhǔn)
①干預(yù)措施不是采用生酮飲食;②原始研究數(shù)據(jù)資料不全;③動(dòng)物試驗(yàn)。
1.3? 資料檢索
檢索數(shù)據(jù)庫為:PubMed、Cochrane Library、EMbase、Sinomed、萬方醫(yī)學(xué)網(wǎng)、維普網(wǎng)等數(shù)據(jù)庫。檢索時(shí)間不限。英文關(guān)鍵詞:Diabetes mellitus、Ketogenic diet、Atkins diet.中文關(guān)鍵詞:糖尿病、生酮飲食。文獻(xiàn)納入內(nèi)容為:第一作者姓名和發(fā)表年限、干預(yù)組和治療組參與人數(shù)、治療手段和持續(xù)時(shí)間、終點(diǎn)指標(biāo)等
1.4? 質(zhì)量評(píng)價(jià)
根據(jù)Jadad評(píng)分量表內(nèi)容:①隨機(jī)化序列的產(chǎn)生是否恰當(dāng);②隨機(jī)化隱藏是否恰當(dāng);③盲法是否恰當(dāng);④撤退與退出描述是否清楚,兩名數(shù)據(jù)提取員對(duì)上述7篇文獻(xiàn)的質(zhì)量進(jìn)行評(píng)價(jià),當(dāng)意見相左時(shí),相互討論是否有合理的達(dá)成一致的方法。
1.5? 統(tǒng)計(jì)方法
將納入的7篇文獻(xiàn)里的數(shù)據(jù)根據(jù)Cochrane系統(tǒng)評(píng)價(jià)手冊進(jìn)行合并,使用ReView Manager5.3軟件對(duì)上述各項(xiàng)研究進(jìn)行Meta分析。對(duì)7篇研究的異質(zhì)性采用I2檢驗(yàn),Cochrane手冊I2值將異質(zhì)性分成4個(gè)程度:①0%~40%為輕度異質(zhì)性;②40%~60%為中度異質(zhì)性;③50%~90%為較大的異質(zhì)性;④75%~100%為很大的異質(zhì)性。Meta分析中效應(yīng)模型的選擇根據(jù)異質(zhì)性檢驗(yàn)結(jié)果而定(若異質(zhì)性<50%,則采用固定效應(yīng)模型;若異質(zhì)性≥50%,則采用隨機(jī)效應(yīng)模型)。使用均數(shù)差(x±s)來描述資料中的連續(xù)性變量。P<0.05為差異有統(tǒng)計(jì)學(xué)意義。
2? 結(jié)果
2.1? 文獻(xiàn)檢索結(jié)果
初次檢索出249篇文獻(xiàn)(英文:243篇中文:27篇,去除重復(fù)文獻(xiàn)16篇,通過閱讀題目和摘要排除掉209篇,最后通過閱讀全文篩選出7篇符合標(biāo)準(zhǔn)的英文文獻(xiàn),各文獻(xiàn)研究類型均為隨機(jī)對(duì)照試驗(yàn),且研究對(duì)象均為人類??偟暮Y選流程圖見圖1。
2.2? 文獻(xiàn)質(zhì)量評(píng)價(jià)
各文獻(xiàn)基本特征及Jadad評(píng)分結(jié)果如圖1所示。根據(jù)Cochrane手冊準(zhǔn)則,7篇納入文獻(xiàn)的偏倚風(fēng)險(xiǎn)圖2及圖3所示。
2.3? Meta分析結(jié)果
2.3.1? Weight森林圖 在對(duì)糖尿病患者的HbA1c變化水平進(jìn)行比較方面,共有5篇文獻(xiàn)研究了該指標(biāo),由于I2=0%,判定納入研究之間沒有異質(zhì)性,使用固定效應(yīng)模型進(jìn)行分析,結(jié)果顯示,干預(yù)組治療前后HbA1c下降水平大于對(duì)照組[MD=-0.50,95%CI(-0.70,-0.30),P<0.01]。見圖4。
2.3.2? Weight森林圖 在對(duì)糖尿病患者的Weight變化水平進(jìn)行比較方面,共有6篇文獻(xiàn)研究了該指標(biāo),由于I2=0%,判定納入研究之間沒有異質(zhì)性,使用固定效應(yīng)模型進(jìn)行分析,結(jié)果顯示,干預(yù)組治療前后Weight下降水平大于對(duì)照組[MD=-8.07,95%CI(-10.73,-5.40),P<0.01]。見圖5。
2.3.3? Triglyceride森林圖 在對(duì)糖尿病患者的Triglyceride變化水平進(jìn)行比較方面,共有6篇文獻(xiàn)研究了該指標(biāo),由于I2=0%,判定納入研究之間沒有異質(zhì)性,使用固定效應(yīng)模型進(jìn)行分析。結(jié)果顯示,干預(yù)組治療前后Triglyceride下降水平大于對(duì)照組[MD=-28.61,95%CI(-46.66,-10.56),P<0.01],見圖6。
2.4? 敏感性分析
改用隨機(jī)效應(yīng)模型后,Meta分析結(jié)果與修改前比較異質(zhì)性變化不大。逐篇剔除各文獻(xiàn)后,Meta分析結(jié)果顯示,異質(zhì)性與剔除前相比變化不大,說明結(jié)果較為穩(wěn)健。
2.5 發(fā)表偏倚檢驗(yàn)
采用繪制漏斗圖方式對(duì)Meta分析結(jié)果進(jìn)行發(fā)表偏倚檢驗(yàn),分別繪制關(guān)于HbA1c、Weight、Triglyceride levels的漏斗圖,觀察圖形發(fā)現(xiàn),這三者的漏斗圖結(jié)果基本對(duì)稱,顯示發(fā)表偏倚較小,見圖7、8、9。
3? 討論
近年來,人們的生活水平不斷提高,不良的飲食習(xí)慣和繁重的都市壓力使得糖尿病的發(fā)病率越來越高,如果糖尿病得不到長期適當(dāng)?shù)木C合治療[15],延緩其進(jìn)展,那么其近期和遠(yuǎn)期并發(fā)癥的發(fā)生率將越來越大,會(huì)嚴(yán)重危害人們的健康。在糖尿病的治療手段中,飲食管理和膳食治療有可能成為治療糖尿病的[16]經(jīng)濟(jì)有效的一種非藥物治療手段[17-18]。生酮飲食[19]作為一種非藥物性的替代性飲食療法,相對(duì)安全有效。
該研究主要從HbA1c、Weight、triglyceride levels這3個(gè)方面來評(píng)價(jià)生酮飲食治療糖尿病患者的有效性:①HbA1c:HbA1c是指血液紅細(xì)胞中的血紅蛋白通過糖化反應(yīng)與血中葡萄糖結(jié)合的產(chǎn)物,一般反應(yīng)人體8~12周的總體血糖水平,人體糖化血紅蛋白水平一般跟血漿葡萄糖的濃度成正比,是檢測血糖變化過程中的一個(gè)有效指標(biāo)。在該研究中,試驗(yàn)組HbA1c水平明顯低于對(duì)照組,差異有統(tǒng)計(jì)學(xué)意義(P<0.05),說明生酮飲食治療糖尿病患者有一定效果。②Weight:糖尿病患者往往都伴有肥胖,而體重的減輕能夠改善糖尿病患者的胰島素抵抗。在該次研究中,試驗(yàn)組采用生酮飲食治療后,明顯減輕了體重,說明了其有效性。③triglyceride levels:生酮飲食[20]能夠降低糖尿病患者甘油三酯水平,改善其脂質(zhì)代謝,減輕其體重,從而改善糖尿病患者病情。
雖然該研究異質(zhì)性較小,敏感性分析后異質(zhì)性很低,結(jié)果相對(duì)可靠,能夠未臨床醫(yī)師在對(duì)糖尿病患者采取治療措施的時(shí)候提供循證醫(yī)學(xué)依據(jù)。但是該研究也存在很多不足:①納入的研究比較少;②納入的病例數(shù)量不是很多;③納入的問文獻(xiàn)全是英文文獻(xiàn),由于各地區(qū)人種,飲食習(xí)慣和生活環(huán)境的不同,生酮飲食治療糖尿病患者效果方面可能存在差異,因此該研究對(duì)國內(nèi)糖尿病患者提供治療依
據(jù)時(shí)可能存在較大局限性。④分析的7篇文獻(xiàn)均為已發(fā)表的文獻(xiàn),未發(fā)表的文獻(xiàn)和其他來源(比如會(huì)議、報(bào)紙等)真實(shí)可靠,具有借鑒意義的資料,因此可能存在一定的發(fā)表偏倚。
[參考文獻(xiàn)]
[1]? Tiruneh SA.Factors influencing diabetes self-care practice among type 2 diabetes patients attending diabetic care follow up at an Ethiopian General Hospital, 2018[J].J Diabetes Metab Disord,2019,18(1):199-206.
[2]? Dambha-Miller H.Association Between Primary Care Practitioner Empathy and Risk of Cardiovascular Events and All-Cause Mortality Among Patients With Type 2 Diabetes: A Population-Based Prospective Cohort Study[J].Ann Fam Med,2019,17(4):311-318.
[3]? Davies MJ.Management of Hyperglycemia in Type 2 Diabetes, 2018. A Consensus Report by the American Diabetes Association(ADA)and the European Association for the Study of Diabetes(EASD)[J].Diabetes Care,2018,41(12):2669-2701.
[4]? Sheng GM.Optimized mid-long term management of ketogenic diet in children with refractory epilepsy[J].J Biol Regul Homeost Agents,2019,33(3):913-918.
[5]? Fan Y.Crosstalk between the Ketogenic Diet and Epilepsy: From the Perspective of Gut Microbiota[J].Mediators Inflamm,2019:8373060.
[6]? Joshi S, RJ Ostfeld, M McMacken.The Ketogenic Diet for Obesity and Diabetes-Enthusiasm Outpaces Evidence[J].JAMA Intern Med, 2019.
[7]? Stocker RK.[Ketogenic Diet and its Evidence-Based Therapeutic Implementation in Endocrine Diseases][J].Praxis (Bern 1994), 2019,108(8):541-553.
[8]? Goday A.Short-term safety, tolerability and efficacy of a very low-calorie-ketogenic diet interventional weight loss program versus hypocaloric diet in patients with type 2 diabetes mellitus[J].Nutr Diabetes,2016,6(9):e230.
[9]? Westman EC.The effect of a low-carbohydrate, ketogenic diet versus a low-glycemic index diet on glycemic control in type 2 diabetes mellitus[J].Nutr Metab (Lond),2008,5:36.
[10]? Saslow LR.Twelve-month outcomes of a randomized trial of a moderate-carbohydrate versus very low-carbohydrate diet in overweight adults with type 2 diabetes mellitus or prediabetes[J].Nutr Diabetes,2017,7(12):304.
[11]? Saslow LR.A randomized pilot trial of a moderate carbohydrate diet compared to a very low carbohydrate diet in overweight or obese individuals with type 2 diabetes mellitus or prediabetes[J].PLoS One,2014,9(4):e91027.
[12]? Saslow LR.An Online Intervention Comparing a Very Low-Carbohydrate Ketogenic Diet and Lifestyle Recommendations Versus a Plate Method Diet in Overweight Individuals With Type 2 Diabetes: A Randomized Controlled Trial[J].J Med Internet Res,2017,19(2):e36.
[13.]? Hussain TA.Effect of low-calorie versus low-carbohydrate ketogenic diet in type 2 diabetes[J].Nutrition,2012,28(10):1016-1021.
[14]? Myette-Cote E.The effect of a short-term low-carbohydrate, high-fat diet with or without postmeal walks on glycemic control and inflammation in type 2 diabetes: a randomized trial[J].Am J Physiol Regul Integr Comp Physiol,2018,315(6):R1210-r1219.
[15]? Petersmann A.Definition, Classification and Diagnosis of Diabetes Mellitus[J].Exp Clin Endocrinol Diabetes, 2018. 126(7):406-410.
[16]? Shestakova MV IA Sklyanik, Dedov, II.Is it possible to achieve sustained remission or cure of type 2 diabetes mellitus in the 21st century[J].Ter Arkh,2017,89(10):4-11.
[17]? Wei JP.Research Progress on Non-Drug Treatment for Blood Glucose Control of Type 2 Diabetes Mellitus[J].Chin J Integr Med,2018,24(10):723-727.
[18]? Corona G.Sexual Dysfunction in Type 2 Diabetes at Diagnosis: Progression over Time and Drug and Non-Drug Correlated Factors[J].PLoS One, 2016,11(10):e0157915.
[19]? Boison D.New insights into the mechanisms of the ketogenic diet[J].Curr Opin Neurol,2017,30(2):187-192.
[20]? Westman EC.Implementing a low-carbohydrate, ketogenic diet to manage type 2 diabetes mellitus[J].Expert Rev Endocrinol Metab,2018,13(5):263-272.
(收稿日期:2019-10-15)