Institute of Metabolism and Endocrinology, The Second Xiangya Hospital and the Diabetes Center, Key Laboratory of Diabetes Immunology, Ministry of Education, Central South University, National Clinical Research Center for Metabolic Diseases, Changsha, Hunan, China.
Diabetes Metab Res Rev. 2020 May;36(4):e3285. doi: 10.1002/dmrr.3285. Epub 2020 Jan 20.
To investigate the association of body mass index (BMI) or BMI z-score (BMIz) at diagnosis with β-cell function in new-onset type 1 diabetes (T1D) patients in children and adults.
This was a retrospective cohort study; 256 children (<18 years) and 245 adults (≥18 years) with less than 1-year duration were recruited and followed for 4 years with an interval of 12 months. Smooth curve fitting, a two-piecewise linear model, and Cox proportional hazards models were utilized to investigate the influence of BMI/BMIz on C-peptide levels.
Heavier patients (BMIz ≥ -1 in children and BMI in adults ≥20.2 kg/m ) had greater C-peptide with a complicated J curve in all age groups after adjustment for age of onset, sex, and disease duration. Moreover, after 4 years of follow-up, patients with higher BMI/BMIz had a lower risk of β-cell failure (HR = 0.7; 95% CI, 0.6-1.0; P = .026). However, no association was found between baseline BMI/BMIz at diagnosis and C-peptide rate of decline during 1 year follow-up.
Association between BMI/BMIz and C-peptide in T1D followed a complicated J curve pattern, and heavier patients had greater C-peptide at diagnosis and a lower risk of β-cell failure at 4 years, suggesting that baseline BMI is a useful predictor for β-cell function in patients with T1D.
研究诊断时体重指数（BMI）或 BMI 标准差评分（BMIz）与新诊断的 1 型糖尿病（T1D）患者的β细胞功能之间的关系。
这是一项回顾性队列研究；共纳入 256 名儿童（<18 岁）和 245 名成人（≥18 岁），其病程均<1 年，随访 4 年，间隔 12 个月。采用平滑曲线拟合、两段线性模型和 Cox 比例风险模型来研究 BMI/BMIz 对 C 肽水平的影响。
在所有年龄组中，调整发病年龄、性别和病程后，较重的患者（BMIz≥-1 的儿童和 BMI≥20.2kg/m 的成人）具有更高的 C 肽水平，且呈复杂的 J 型曲线。此外，在 4 年的随访后，较高 BMI/BMIz 的患者β细胞衰竭的风险较低（HR=0.7；95%CI，0.6-1.0；P=0.026）。然而，在 1 年的随访期间，基线诊断时的 BMI/BMIz 与 C 肽的下降率之间并无关联。
T1D 患者的 BMI/BMIz 与 C 肽之间呈复杂的 J 型曲线关系，较重的患者在诊断时具有更高的 C 肽水平，在 4 年时β细胞衰竭的风险较低，这表明基线 BMI 是预测 T1D 患者β细胞功能的一个有用指标。
