Study on the accuracy of glomerular filtration rate formulas by double plasma method as "gold standard"

Objective: To evaluate the accuracy of glomerular filtration rate formula by comparising the CKD-EPI 2009 formula and the modified Modified MDRD formula with the 99mTc-DTPA double-phase plasma method as "gold standard" respectively. Methods: Totally 166 patients diognosed as chronic kidney disease (CKD) were enrolled. The 99mTc-DTPA double-plasma method (rGFR) was used as the "gold standard". The CKD-EPI 2009 formula and the modified MDRD formula were used to calculate eGFR. Statistical software was used to analyze the correlation between the calculated values of the two formulas and the gold standard value and the bias. Then we evaluated the accuracy of the two GFR formulas. Results: Among the CKD stage 1 patients, the bias of the CKD-EPI 2009 formula was smaller than that of the Modified MDRD formula (13.9911.45;20.1815.90);both formulas were weakly correlated with the gold standard (correlation coefficients were 0.216, 0.229, P<0.01, respectively);The probability that the bias of the calculated value of the CKD-EPI 2009 formula less than 15%, 30%, and 50% of the gold standard value is smaller. Among the CKD stage 2 patients, the bias of the CKD-EPI 2009 formula was smaller than that of the Modified MDRD formula (12.748.45;15.6811.01);both formulas were moderately correlated with the gold standard (correlation coefficients were 0.568, 0.581, P<0.01, respectively);The probability that the bias of the calculated value of the CKD-EPI 2009 formula less than 15%, 30%, and 50% of the gold standard value is smaller. Among the CKD stage 3 patients, the bias of the CKD-EPI 2009 formula was smaller than that of the Modified MDRD formula (12.6410.27;12.8810.97), and both formulas were strongly correlated with the gold standard (correlation coefficients were 0.664, 0.670, P<0.01, respectively);The probability that the bias of the calculated value of the Modified MDRD formula less than 15%, 30%, and 50% of the gold standard value is smaller. Among the CKD stage 4 to 5 patients, the bias of the CKD-EPI 2009 formula was smaller than that of the Modified MDRD formula (5.585.36;5.945.20);The CKD-EPI 2009 formula and the Modified MDRD formula were strongly correlated with the gold standard (correlation coefficient r was 0.808. 0.802, P<0.01, respectively);The probability of the bias of the calculated value of the CKD-EPI 2009 formula less than 15%, 30%, and 50% of the gold standard value is smaller. In patients with decreased renal function with GFR <60 ml/min, the sensitivity and positive predictive value of the CKD-EPI 2009 formula for the diagnosis of "decreased renal function"were higher, and the specificity was comparable. Conclusion: 1. When the renal function is only slightly decreased, the accuracy of the two formulas is not good. In this condition, the CKD-EPI 2009 formula is more accurate and recommended. 2. It is necessary to further improve the current formulas especialy when it comes to value the slightly declined renal function;3. When we try to identify the stage of CKD patients, only based on eGFR may cause misclassification, it is recommended to combine the cause-GFR-albuminuria staging to assess the stage of CKD;4. The current formulas have limitations.in the case that requires a highly accurate assessment of GFR, the 99mTc-DTPA dual plasma method is recommended.

2021慢性肾脏病流行病学合作研究CKD-EPI和欧洲肾脏功能联盟EKFC估算肾小球滤过率公式的临床应用评估

目的评估2021慢性肾脏病流行病学合作研究(CKD-EPI)和欧洲肾脏功能联盟(EKFC)估算肾小球滤过率公式在中国人群的临床应用效果。方法入组2023年1月1日至12月31日于复旦大学附属中山医院就诊的患者和健康体检者, 排除年龄小于18岁、妊娠状态、肌肉相关疾病、超滤状态和透析患者后共660 078例, 年龄58(44, 68)岁, 男性占56.51%(372 987/660 078), 每人选取第一次肌酐检测结果。按不同性别、年龄、肌酐结果比较2021 CKD-EPI和EKFC公式与科室现用2009 CKD-EPI公式 eGFRcr结果之间的差异(P10)、人群分布改变, 以及对慢性肾脏病(CKD)分期的影响。结果 2021与2009 CKD-EPI eGFRcr结果相比, P10为99.99%(R^(2)=0.997), 2021CKD-EPI eGFRcr整体偏高3.77(2.92, 4.47)ml/(min×1.73 m^(2))。应用2021CKD-EPI公式后, 86.42%(570 455/660 078)偏高且CKD分期一致, 12.35%(81 514/660 078)偏高而分期不同;1.23%(8 109/660 078)eGFRcr结果偏低且分期一致。EKFC eGFRcr与2009 CKD-EPI eGFRcr结果相比, P10为89.79%(R^(2)=0.976), EKFC eGFRcr总体偏低4.63(-2.22, -7.04)ml/(min×1.73 m^(2))。应用EKFC公式后, 75.14%(495 992/660 078)eGFRcr结果偏低且分期一致, 15.63%(103 161/660 078)人结果偏低而CKD分期不同;8.80%(58 077/660 078)eGFRcr结果偏高且分期一致, 0.43%(2 848/660 078)结果偏高而CKD分期不同。结论与2009 CKD-EPI eGFRcr结果相比, 2021 CKD-EPI eGFRcr结果在不同性别和年龄的人群中一致性好, 结果整体略高;而EKFC eGFRcr与2009 CKD-EPI eGFRcr相比一致性较差, 结果整体偏低。在判断患者CKD分期时, 应考虑应用不同eGFR公式带来的影响。

用99mTc-DTPA双血浆法评估肾小球滤过率公式的准确性

目的:以99mTc-DTPA双血浆法(99mTc-DTPAdouble-phase plasma method)为“金标准”,分析CKD-EPI 2009公式及改良MDRD公式评估肾小球滤过率的准确性。方法:收集慢性肾脏病(chronickidney disease,CKD)1~5期患者166例,以99mTc-DTPA双血浆法测得值(rGFR)为“金标准”,应用CKD-EPI 2009公式和改良的MDRD公式计算eGFR,使用统计软件分析2个公式计算值与rGFR的相关性及偏倚等指标,评价公式法评估GFR在不同CKD分期中的准确性。结果:CKD1期患者中,CKD-EPI 2009公式的偏倚较改良MDRD公式小;CKD-EPI 2009公式和改良MDRD公式均与rGFR呈弱相关(P<0.01);CKD-EPI 2009公式计算值的误差小于15%、30%、50%rGFR的概率更小。CKD2期患者中,CKD-EPI 2009公式的偏倚较改良MDRD公式小;两公式均与rGFR呈中等程度相关(P<0.01);CKD-EPI 2009公式计算值的误差小于15%、30%、50%rGFR的概率更小。CKD3期患者中,CKD-EPI 2009公式的偏倚较改良MDRD公式小,两个公式均与rGFR呈强相关(P<0.01);改良MDRD公式计算值的误差小于15%、30%、50%rGFR的概率更小。CKD4期和5期患者中,CKD-EPI 2009公式的偏倚较改良MDRD公式小;两个公式与rGFR均为极强相关(P<0.01);CKD-EPI 2009公式计算值的误差小于15%、30%、50%rGFR的概率更小。在GFR<60 mL/min的患者中,CKD-EPI 2009公式诊断“肾功能下降”的灵敏度及阳性预期值更高,特异度两者相当。结论:⑴在肾功能仅轻度下降时两个公式准确性均欠佳,此时CKD-EPI 2009公式相比之下更为准确,推荐使用;⑵还需进一步改进目前的公式,以提高其对肾功能下降早期GFR的评估效能;⑶对CKD患者进行临床分期时,仅依据eGFR是可能造成分期误判的,建议联合病因-GFR-白蛋白尿分期来评估病情。

Physics as Final Opportunity to Prevent Harms Related to Theatricalization of Meteorology

Using Mbane Biouele formula derived in 2009 on the troposphere thermoelastic properties leads to thermal and kinematic profiles of major atmospheric disturbances which clearly indicate that these terrible events for men should not be viewed with fatalism. This unexpected truth is unfortunately always obscured by media outlets of brilliant TV presenters or famous workshops panelists that focus attention on the excessively sensational meteorology (unfortunately folk and pernicious) instead of worrying about the seriousness that should characterize all interventions on the climate study or prediction. Good weather conditions, it is undeniable, facilitate an excellent running of almost all human activities like sports, transport, agricultural activities, celebrations of events, etc.... Far more serious, the advent of supercomputers and satellites could, if their valuable information is used solely for the theatricalization of weather events, trigger the decline of the scientific discipline of great public utility that is meteorology. Indeed, many meteorologists acquire very big head when they succeed in acquiring advanced equipment. Without prejudging what meteorology will become in the future, we hope that the work done in this article will remind each researchers that much remains to be done to promote climate studies. We remind quite emphatically that both hurricanes and cyclones have their weak-points (or talon d’Achilles in French) and thus, researchers should begin to think about “how to neutralize atmospheric disturbances that have both a large and a strong destructive power”.