Department of Nephrology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China.
Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China.
Sci Rep. 2021 May 12;11(1):10058. doi: 10.1038/s41598-021-89565-x.
Blood urea nitrogen (BUN) is a nitrogenous end product of protein metabolism. This study aims to explore the age- and sex-specific distribution of BUN among healthy Chinese adults. A total of 24,006 BUN values from healthy adults (14,148 males and 9858 females) were included in the cross-sectional study. Males had a higher median BUN value compared to females (4.6 mmol/L vs. 4.1 mmol/L). BUN values showed a positive correlation with body mass index (BMI), cholesterol, and blood sugar (P < 0.0001). However, eGFR showed a negative correlation with the BUN reference value (P < 0.0001) in both sexes. Multiple linear regression analysis confirmed that the positive associations of BUN levels and age were statistically significant after adjusting confounding factors (P < 0.001). Thus, the serum BUN values increased by 0.21 mmol/L for males and 0.282 mmol/L for females per 10 years. The BUN values corresponding to the 1st, 2.5th, 50th, 97.5th, and 99th percentiles for any specific age in both sex were also calculated. These results indicate that the serum BUN reference value is significantly affected by age and gender, and thus, its interpretation is age- and sex-dependent.
血尿素氮 (BUN) 是蛋白质代谢的氮终产物。本研究旨在探讨健康中国成年人中 BUN 的年龄和性别特异性分布。共有 24006 例健康成年人（男性 14148 例，女性 9858 例）的 BUN 值纳入了这项横断面研究。男性的 BUN 中位数高于女性（4.6mmol/L 比 4.1mmol/L）。BUN 值与体重指数（BMI）、胆固醇和血糖呈正相关（P<0.0001）。然而，eGFR 与男女的 BUN 参考值呈负相关（P<0.0001）。多元线性回归分析证实，在调整混杂因素后，BUN 水平与年龄的正相关具有统计学意义（P<0.001）。因此，男性和女性的 BUN 值每增加 10 岁分别增加 0.21mmol/L 和 0.282mmol/L。还计算了任何特定年龄在两性中第 1、2.5、50、97.5 和 99 百分位对应的 BUN 值。这些结果表明，血清 BUN 参考值受年龄和性别显著影响，因此其解释依赖于年龄和性别。
