Section on Ethnicity and Health, Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States.
Hypertension in Africa Research Team, North-West University, Potchefstroom, South Africa.
Front Public Health. 2022 Sep 23;10:941086. doi: 10.3389/fpubh.2022.941086. eCollection 2022.
Emerging data suggests that in sub-Saharan Africa β-cell-failure in the absence of obesity is a frequent cause of type 2 diabetes (diabetes). Traditional diabetes risk scores assume that obesity-linked insulin resistance is the primary cause of diabetes. Hence, it is unknown whether diabetes risk scores detect undiagnosed diabetes when the cause is β-cell-failure.
In 528 African-born Blacks living in the United States [age 38 ± 10 (Mean ± SE); 64% male; BMI 28 ± 5 kg/m] we determined the: (1) prevalence of previously undiagnosed diabetes, (2) prevalence of diabetes due to β-cell-failure vs. insulin resistance; and (3) the ability of six diabetes risk scores [Cambridge, Finnish Diabetes Risk Score (FINDRISC), Kuwaiti, Omani, Rotterdam, and SUNSET] to detect previously undiagnosed diabetes due to either β-cell-failure or insulin resistance.
Diabetes was diagnosed by glucose criteria of the OGTT and/or HbA1c ≥ 6.5%. Insulin resistance was defined by the lowest quartile of the Matsuda index (≤ 2.04). Diabetes due to β-cell-failure required diagnosis of diabetes in the absence of insulin resistance. Demographics, body mass index (BMI), waist circumference, visceral adipose tissue (VAT), family medical history, smoking status, blood pressure, antihypertensive medication, and blood lipid profiles were obtained. Area under the Receiver Operator Characteristics Curve (AROC) estimated sensitivity and specificity of each continuous score. AROC criteria were: Outstanding: >0.90; Excellent: 0.80-0.89; Acceptable: 0.70-0.79; Poor: 0.50-0.69; and No Discrimination: 0.50.
Prevalence of diabetes was 9% (46/528). Of the diabetes cases, β-cell-failure occurred in 43% (20/46) and insulin resistance in 57% (26/46). The β-cell-failure group had lower BMI (27 ± 4 vs. 31 ± 5 kg/m < 0.001), lower waist circumference (91 ± 10 vs. 101 ± 10cm < 0.001) and lower VAT (119 ± 65 vs. 183 ± 63 cm, < 0.001). Scores had indiscriminate or poor detection of diabetes due to β-cell-failure (FINDRISC AROC = 0.49 to Cambridge AROC = 0.62). Scores showed poor to excellent detection of diabetes due to insulin resistance, (Cambridge AROC = 0.69, to Kuwaiti AROC = 0.81).
At a prevalence of 43%, β-cell-failure accounted for nearly half of the cases of diabetes. All six diabetes risk scores failed to detect previously undiagnosed diabetes due to β-cell-failure while effectively identifying diabetes when the etiology was insulin resistance. Diabetes risk scores which correctly classify diabetes due to β-cell-failure are urgently needed.
新兴数据表明，在撒哈拉以南非洲，β细胞衰竭而不伴肥胖是 2 型糖尿病（糖尿病）的常见病因。传统的糖尿病风险评分假设肥胖相关的胰岛素抵抗是糖尿病的主要病因。因此，尚不清楚当病因是β细胞衰竭时，糖尿病风险评分是否能检测到未确诊的糖尿病。
在 528 名居住在美国的非洲出生的黑人中[年龄 38 ± 10（平均值 ± SE）；64%为男性；BMI 28 ± 5kg/m]，我们确定了：（1）先前未确诊的糖尿病的患病率，（2）β细胞衰竭与胰岛素抵抗所致糖尿病的患病率；以及（3）六种糖尿病风险评分[剑桥、芬兰糖尿病风险评分（FINDRISC）、科威特、阿曼、鹿特丹和 SUNSET]检测由于β细胞衰竭或胰岛素抵抗导致的先前未确诊糖尿病的能力。
通过 OGTT 和/或 HbA1c≥6.5%的血糖标准诊断糖尿病。胰岛素抵抗定义为 Matsuda 指数最低四分位数（≤2.04）。由于β细胞衰竭导致的糖尿病需要在没有胰岛素抵抗的情况下诊断糖尿病。获得了人口统计学数据、体重指数（BMI）、腰围、内脏脂肪组织（VAT）、家族医疗史、吸烟状况、血压、降压药物和血脂谱。接收者操作特征曲线（ROC）下的面积（AUC）估计了每个连续评分的敏感性和特异性。AUC 标准为：出色：>0.90；优秀：0.80-0.89；可接受：0.70-0.79；差：0.50-0.69；无区分：0.50。
糖尿病的患病率为 9%（46/528）。在这些糖尿病病例中，β细胞衰竭占 43%（20/46），胰岛素抵抗占 57%（26/46）。β细胞衰竭组的 BMI（27 ± 4 与 31 ± 5kg/m，<0.001）、腰围（91 ± 10 与 101 ± 10cm，<0.001）和 VAT（119 ± 65 与 183 ± 63cm，<0.001）均较低。评分对β细胞衰竭所致糖尿病的检测存在不可区分或较差（FINDRISC AUC=0.49 至剑桥 AUC=0.62）。评分对胰岛素抵抗所致糖尿病的检测显示出较差到优秀的效果（剑桥 AUC=0.69，科威特 AUC=0.81）。
在 43%的患病率下，β细胞衰竭几乎占糖尿病病例的一半。所有六种糖尿病风险评分都未能检测到由于β细胞衰竭导致的先前未确诊的糖尿病，而当病因是胰岛素抵抗时，这些评分能有效识别糖尿病。迫切需要能够正确分类β细胞衰竭所致糖尿病的糖尿病风险评分。
