Background: Clinical practice guidelines recommend objective nutritional assessments in managing chronic kidney disease (CKD) patients but were developed while referencing to a North-American population. Specific recommendations for assessing muscle mass were suggested (mid-arm circumference, MAC; corrected mid-arm muscle area, cAMA; mid-arm muscle circumference, MAMC). This study aimed to assess correlation and association of these assessments with dietary protein intake in a multi-ethnic Asian population of healthy and CKD patients.
Methods: We analyzed 24-hour urine collections of selected participants to estimate total protein intake (TPI; g/day). Ideal body weight (IDW; kg) was calculated and muscle assessments conducted. Analyses involved correlation and linear regression, taking significance at p<0.05.
Results: There were 232 stable CKD patients and 103 healthy participants comprising of 51.0% male, 38.5% Chinese, 29.6% Malay, 23.6% Indian, and 8.4% others. The mean TPI was 58.9 ± 18.4 g/day in healthy participants and 53.6 ± 19.4 g/day in CKD patients. When normalized to ideal body weight, TPI-IDW (g/kg/day) was similar in healthy and CKD participants. Overall, TPI was associated with MAC (r=0.372, p<0.001), cAMA (r=0.337, p<0.001), and MAMC (r=0.351, p<0.001). TPI-IDW was also associated with MAC (r=0.304, p<0.001), cAMA (r=0.202, p<0.001), and MAMC (r=0.200, p<0.001) but not for TPI normalized to actual body weight. When examined separately, TPI was associated with MAC, cAMA, and MAMC in both CKD and healthy participants, but was associated with TPI-IDW only in CKD patients.
Conclusion: Total protein intake was associated with muscle assessments in all participants. TPI normalized to IDW should only be used in CKD patients.
背景：在慢性肾脏病患者的管理中，临床实践指南推荐的客观营养评估是参 考北美人群开发的。具体的肌肉质量评估建议如下：中臂围（MAC）、校正 的中臂肌肉面积（cAMA）和中臂肌围（MAMC）。本研究的目的是在多民族 亚裔人群中评估健康人和慢性肾脏病患者肌肉质量与膳食蛋白质摄入量之间的 关系。方法：我们分析了所收集的参与者24 小时尿来估算总蛋白质摄入量 （TPI，克/天）。计算理想体重（IDW，千克）并评估肌肉。应用相关性和线 性回归分析，显著性定义为p<0.05。结果：共有232 名稳定的慢性肾脏病患 者和103 名健康志愿者参加，其平均年龄为53.5±15.1 岁， 51.0%为男性，其 中华人占38.5%、马来人占29.6%、印度人占23.6%、其他民族的人占8.4%。 健康志愿者和慢性肾脏病患者的TPI 分别为58.9±18.4 克/天和53.6±19.4 克/ 天。当标准化为理想体重，健康志愿者和慢性肾脏病患者的TPI-IDW（克/千 克/日）相似。总体来看，TPI 与MAC、cAMA 和MAMC 相关，相关系数分 别为：0.372、0.337 和0.351（p<0.001)。TPI-IDW 也与MAC、cAMA 和 MAMC 相关，相关系数分别为：0.304、0.202 和0.200（p<0.001），但是TPI 标准化为实际体重与这些肌肉质量评估参数没有相关性。当单独分析时， MAC、cAMA 和MAMC 与健康志愿者和慢性肾脏病患者的TPI 都有关，但只 与慢性肾脏病患者的TPI-IDW 有关。结论：总蛋白质摄入量与所有参与者的 肌肉评估有关，TPI 标准化为理想体重只适用于慢性肾脏病患者。