PDF(Pubmed)
Abstract：
BACKGROUND: Understanding how race may influence the association between A1c and glycemia can improve diabetes screening. We sought to determine whether, for a given A1c level, glucose levels during an oral glucose tolerance test (OGTT) differed by race.
METHODS: From data collected at 22 US clinical sites, we conducted a cross-sectional study of concurrently measured A1c and OGTT and observational longitudinal follow-up of the subset with high-risk pre-diabetes. Numerical integration methods were used to calculate area under the glycemic curve (AUCglu) during OGTT and least squares regression model to estimate A1c for a given AUCglu by race, controlling for potential confounders.
RESULTS: 1016 black, 2658 white, and 193 Asian persons at risk of diabetes were included in cross-sectional analysis. Of these, 2154 with high-risk pre-diabetes were followed for 2.5 years. For a given A1c level, AUCglu was lower in black versus white participants. After adjustment for potential confounders, A1c levels for a given AUCglu quintile were 0.15-0.20 and 0.02-0.19 percentage points higher in black and Asian compared with white participants, respectively (p<0.05). In longitudinal analyses, black participants were more likely to be diagnosed with diabetes by A1c than white participants (28% vs 10%, respectively; p<0.01). Black and Asian participants were less likely to be diagnosed by fasting glucose than white participants (16% vs 15% vs 37%, respectively; p<0.05). Black participants with A1c levels in the lower-level quintiles had greater increase in A1c over time compared with white participants.
CONCLUSIONS: Use of additional testing beyond A1c to screen for diabetes may better stratify diabetes risk in the diverse US population.
METHODS: From data collected at 22 US clinical sites, we conducted a cross-sectional study of concurrently measured A1c and OGTT and observational longitudinal follow-up of the subset with high-risk pre-diabetes. Numerical integration methods were used to calculate area under the glycemic curve (AUCglu) during OGTT and least squares regression model to estimate A1c for a given AUCglu by race, controlling for potential confounders.
RESULTS: 1016 black, 2658 white, and 193 Asian persons at risk of diabetes were included in cross-sectional analysis. Of these, 2154 with high-risk pre-diabetes were followed for 2.5 years. For a given A1c level, AUCglu was lower in black versus white participants. After adjustment for potential confounders, A1c levels for a given AUCglu quintile were 0.15-0.20 and 0.02-0.19 percentage points higher in black and Asian compared with white participants, respectively (p<0.05). In longitudinal analyses, black participants were more likely to be diagnosed with diabetes by A1c than white participants (28% vs 10%, respectively; p<0.01). Black and Asian participants were less likely to be diagnosed by fasting glucose than white participants (16% vs 15% vs 37%, respectively; p<0.05). Black participants with A1c levels in the lower-level quintiles had greater increase in A1c over time compared with white participants.
CONCLUSIONS: Use of additional testing beyond A1c to screen for diabetes may better stratify diabetes risk in the diverse US population.
摘要：
背景：了解种族如何影响A1c和血糖之间的关联可以改善糖尿病筛查。我们试图确定，对于给定的A1c水平，口服葡萄糖耐量试验（OGTT）期间的葡萄糖水平因种族而异。
方法：从22个美国临床站点收集的数据中，我们进行了一项横断面研究,包括同时测量的A1c和OGTT,以及对高危糖尿病前期亚组的观察性纵向随访.使用数值积分方法计算OGTT期间的血糖曲线下面积（AUCglu）和最小二乘回归模型来估计按种族给定AUCglu的A1c，控制潜在的混杂因素。
结果：1016黑色，2658白色，有糖尿病风险的193名亚洲人被纳入横断面分析.其中,2154名高风险糖尿病前期患者随访2.5年。对于给定的A1c水平，黑人和白人参与者的AUCglu较低。在调整了潜在的混杂因素后，与白人参与者相比，黑人和亚洲人的A1c水平分别高出0.15-0.20和0.02-0.19个百分点，分别为(p<0.05)。在纵向分析中，黑人参与者比白人参与者更有可能被A1c诊断为糖尿病(28%vs10%，分别为；p<0.01)。与白人参与者相比，黑人和亚洲参与者被空腹血糖诊断的可能性较小（16％vs15％vs37％，分别为；p<0.05)。与白人参与者相比，A1c水平处于较低水平五分位数的黑人参与者随着时间的推移A1c的增加更大。
结论：使用A1c以外的额外检测来筛查糖尿病可能更好地对不同美国人群的糖尿病风险进行分层。
方法：从22个美国临床站点收集的数据中，我们进行了一项横断面研究,包括同时测量的A1c和OGTT,以及对高危糖尿病前期亚组的观察性纵向随访.使用数值积分方法计算OGTT期间的血糖曲线下面积（AUCglu）和最小二乘回归模型来估计按种族给定AUCglu的A1c，控制潜在的混杂因素。
结果：1016黑色，2658白色，有糖尿病风险的193名亚洲人被纳入横断面分析.其中,2154名高风险糖尿病前期患者随访2.5年。对于给定的A1c水平，黑人和白人参与者的AUCglu较低。在调整了潜在的混杂因素后，与白人参与者相比，黑人和亚洲人的A1c水平分别高出0.15-0.20和0.02-0.19个百分点，分别为(p<0.05)。在纵向分析中，黑人参与者比白人参与者更有可能被A1c诊断为糖尿病(28%vs10%，分别为；p<0.01)。与白人参与者相比，黑人和亚洲参与者被空腹血糖诊断的可能性较小（16％vs15％vs37％，分别为；p<0.05)。与白人参与者相比，A1c水平处于较低水平五分位数的黑人参与者随着时间的推移A1c的增加更大。
结论：使用A1c以外的额外检测来筛查糖尿病可能更好地对不同美国人群的糖尿病风险进行分层。
