Jacobs Anne, Benraad Carolien, Wetzels Jack, Rikkert Marcel Olde, Kramers Cornelis
Department of Geriatrics, Radboudumc, Nijmegen, The Netherlands.
Department of Geriatric Psychiatry, Pro Persona Mental Health Care, Nijmegen/Arnhem, The Netherlands.
Drugs Aging. 2017 Jun;34(6):445-452. doi: 10.1007/s40266-017-0460-z.
The risk of incorrect medication dosing is high in frail older people. Therefore, accurate assessment of the glomerular filtration rate is important.
The objective of this study was to compare the estimated glomerular filtration rate using creatinine- and cystatin C-based formulae, the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations, in frail older people. We hypothesized that frailty determines the difference between the creatinine- and cystatin C-based formulae.
The mean difference between CKD-EPI creatinine and cystatin C was determined using (cross-sectional) data of 55 patients (mean age 73 years) admitted to a psychiatric ward for older adults. The level of agreement of these estimations was assessed by a Bland-Altman analysis. In all patients, the Rockwood's Frailty Index was derived and correlated with the mean difference between CKD-EPI creatinine and cystatin C.
The mean difference between CKD-EPI creatinine (mean 71.2 mL/min/1.73 m) and CKD-EPI cystatin C (mean 57.6 mL/min/1.73 m) was 13.6 mL/min/1.73 m (p < 0.0001). The two standard deviation limit in the Bland-Altman plot was large (43.2 mL/min/1.73 m), which represents a low level of agreement. The Frailty Index did not correlate with the mean difference between the creatinine- and cystatin C-based glomerular filtration rate (Pearson correlation coefficient 0.182, p = 0.184).
There was a significant gap between a creatinine- and cystatin C-based estimation of glomerular filtration rate, irrespective of frailty. The range of differences between the commonly used estimated glomerular filtration rate formulae might result in clinically relevant differences in drug prescription and differences in chronic kidney disease staging.
体弱的老年人用药剂量错误的风险很高。因此，准确评估肾小球滤过率很重要。
本研究的目的是比较基于肌酐和胱抑素C的公式（慢性肾脏病流行病学合作组（CKD-EPI）方程）估算的肾小球滤过率在体弱老年人中的情况。我们假设虚弱决定了基于肌酐和胱抑素C的公式之间的差异。
使用55名（平均年龄73岁）入住老年精神科病房患者的（横断面）数据，确定CKD-EPI肌酐和胱抑素C之间的平均差异。通过Bland-Altman分析评估这些估算值的一致性水平。在所有患者中，得出Rockwood虚弱指数，并将其与CKD-EPI肌酐和胱抑素C之间的平均差异相关联。
CKD-EPI肌酐（平均71.2 mL/min/1.73m²）和CKD-EPI胱抑素C（平均57.6 mL/min/1.73m²）之间的平均差异为13.6 mL/min/1.73m²（p < 0.0001）。Bland-Altman图中的两倍标准差限值很大（43.2 mL/min/1.73m²），这表明一致性水平较低。虚弱指数与基于肌酐和胱抑素C的肾小球滤过率之间的平均差异无相关性（Pearson相关系数0.182，p = 0.184）。
无论是否虚弱，基于肌酐和胱抑素C的肾小球滤过率估算之间存在显著差距。常用的估算肾小球滤过率公式之间的差异范围可能导致药物处方方面的临床相关差异以及慢性肾脏病分期的差异。
