Endocrine Unit, Dept of Internal Medicine, Faculty of Medicine, Universiti Teknologi MARA (UiTM), Shah Alam, Malaysia.
Centre for Dietetics Studies, Faculty of Health Sciences, Universiti Teknologi MARA (UiTM), Puncak Alam, Selangor.
PLoS One. 2021 Oct 13;16(10):e0258507. doi: 10.1371/journal.pone.0258507. eCollection 2021.
There is limited data on the effects of low carbohydrate diets on renal outcomes particularly in patients with underlying diabetic kidney disease. Therefore, this study determined the safety and effects of very low carbohydrate (VLCBD) in addition to low protein diet (LPD) on renal outcomes, anthropometric, metabolic and inflammatory parameters in patients with T2DM and underlying mild to moderate kidney disease (DKD).
This was an investigator-initiated, single-center, randomized, controlled, clinical trial in patients with T2DM and DKD, comparing 12-weeks of low carbohydrate diet (<20g daily intake) versus standard low protein (0.8g/kg/day) and low salt diet. Patients in the VLCBD group underwent 2-weekly monitoring including their 3-day food diaries. In addition, Dual-energy x-ray absorptiometry (DEXA) was performed to estimate body fat percentages.
The study population (n = 30) had a median age of 57 years old and a BMI of 30.68kg/m2. Both groups showed similar total calorie intake, i.e. 739.33 (IQR288.48) vs 789.92 (IQR522.4) kcal, by the end of the study. The VLCBD group showed significantly lower daily carbohydrate intake 27 (IQR25) g vs 89.33 (IQR77.4) g, p<0.001, significantly higher protein intake per day 44.08 (IQR21.98) g vs 29.63 (IQR16.35) g, p<0.05 and no difference in in daily fat intake. Both groups showed no worsening of serum creatinine at study end, with consistent declines in HbA1c (1.3(1.1) vs 0.7(1.25) %) and fasting blood glucose (1.5(3.37) vs 1.3(5.7) mmol/L). The VLCBD group showed significant reductions in total daily insulin dose (39(22) vs 0 IU, p<0.001), increased LDL-C and HDL-C, decline in IL-6 levels; with contrasting results in the control group. This was associated with significant weight reduction (-4.0(3.9) vs 0.2(4.2) kg, p = <0.001) and improvements in body fat percentages. WC was significantly reduced in the VLCBD group, even after adjustments to age, HbA1c, weight and creatinine changes. Both dietary interventions were well received with no reported adverse events.
This study demonstrated that dietary intervention of very low carbohydrate diet in patients with underlying diabetic kidney disease was safe and associated with significant improvements in glycemic control, anthropometric measurements including weight, abdominal adiposity and IL-6. Renal outcomes remained unchanged. These findings would strengthen the importance of this dietary intervention as part of the management of patients with diabetic kidney disease.
关于低碳水化合物饮食对肾脏结局的影响的数据有限，尤其是在患有糖尿病肾病的患者中。因此，本研究旨在确定极低碳水化合物（VLCBD）饮食除了低蛋白饮食（LPD）以外，对 T2DM 合并轻度至中度肾脏疾病（DKD）患者的肾脏结局、人体测量、代谢和炎症参数的安全性和影响。
这是一项由研究者发起的、单中心、随机、对照、临床试验，纳入了 T2DM 和 DKD 患者，比较了 12 周的低碳水化合物饮食（<20g 日摄入量）与标准低蛋白（0.8g/kg/天）和低盐饮食。VLCBD 组的患者每两周进行一次监测，包括他们的 3 天饮食日记。此外，还进行了双能 X 射线吸收法（DEXA）以估计体脂肪百分比。
研究人群（n=30）的中位年龄为 57 岁，BMI 为 30.68kg/m2。两组在研究结束时的总热量摄入相似，分别为 739.33（IQR288.48）和 789.92（IQR522.4）千卡。VLCBD 组的每日碳水化合物摄入量明显较低，为 27（IQR25）克，而 89.33（IQR77.4）克，p<0.001，每日蛋白质摄入量明显较高，为 44.08（IQR21.98）克，而 29.63（IQR16.35）克，p<0.05，每日脂肪摄入量无差异。两组患者的血清肌酐在研究结束时均无恶化，HbA1c（1.3（1.1）vs 0.7（1.25）%）和空腹血糖（1.5（3.37）vs 1.3（5.7）mmol/L）均持续下降。VLCBD 组的总日胰岛素剂量显著减少（39（22）vs 0 IU，p<0.001），LDL-C 和 HDL-C 升高，IL-6 水平下降；而对照组的结果则相反。这与体重显著减轻（-4.0（3.9）vs 0.2（4.2）kg，p<0.001）和体脂肪百分比的改善有关。即使在调整年龄、HbA1c、体重和肌酐变化后，VLCBD 组的 WC 仍显著降低。两种饮食干预均被很好地接受，没有报告不良事件。
本研究表明，患有糖尿病肾病的患者进行极低碳水化合物饮食的饮食干预是安全的，并与血糖控制的显著改善、人体测量指标（包括体重、腹部肥胖和 IL-6）有关。肾脏结局没有改变。这些发现将加强这种饮食干预作为糖尿病肾病患者管理的一部分的重要性。
