INVESTIGADORES
FERNANDEZ Elmer Andres
artículos
Título:
Comparison of different methods for hemodialysis evaluation by means of ROC curves: from artificial intelligence to current methods
Autor/es:
FERNÁNDEZ, ELMER ANDRÉS; VALTUILLE, RODOLFO; PRESEDO, JESUS RODRIGUEZ; WILLSHAW, PETER
Revista:
CLINICAL NEPHROLOGY
Referencias:
Año: 2005 vol. 64 p. 205 - 213
ISSN:
0301-0430
Resumen:
Abstract:
The National Kidney Foundation Guidelines (DOQI) and the European Renal
Association (ERA) have set standards for
adequacy of hemodialysis treatment. They recommended minimum single pool doses
of 1.2 (Kt/Vsp DOQI), and 1.4 (Kt/Vsp ERA) and a "standard" urea
removal ratio (URR) of 65%. Here we compare an Artificial Intelligence Method
(AIM) based on an Artificial Neural Network (ANN) and the usual methods for
hemodialysis treatment follow-up such as Smye, Daugirdas, standard Urea
Reduction Ratio (URR using postdialysis urea concentration) and modified URR
[Cheng et al. 2001] against equilibrated Kt/V and URR calculated using a 60
minute postdialysis urea concentration.
Method:
We used ROC analysis to evaluate
and compare these methodologies. We also propose a method to find a minimum
target dose that maximizes the Sensitivity , Specificity and Positive
Predictive Values of the diagnostic tool.
Results:
From a URR point of view the ANN, stdURR and mURR perform almost equally well
with an area under the curve (AUC) of 0.90, 0.93 and 0.92 respectively but the
ANN achieved the lowest False Positive Rate (FPR=7.94%) and Error Rate
(ER=12.7%). When Kt/V is used as a dose index, the logarithmic single and
double pool equations perform almost equally (AUC 0.957 and 0.962) and the ANN
method achieves an AUC of 0.934. The lowest FPR were for ANN and Kt/Vsp (4.76%)
which also achieved the lowest ER of 6.39%.
Conclusion:
For both cases (URR and Kt/V) the minimum doses required to achieve the lowest
FPR and ER for the standard methods (stdURR and Kt/Vsp) were higher than those
reported by the DOQI guidelines, being 70% for stdURR and 1.35 for Kt/Vsp;
whereas for those methods using the double pool Kt/V or equilibrated URR the
dose targets were close to those recommended by DOQI and ERA.
Our
proposed method for target dose selection is easy to understand and it takes
into account both accuracy and confidence of the adequacy tool.
We found the ANN
method to be superior to the Smye method for estimation of equilibrated urea,
and the results presented here suggest that ANN methods could be useful tools
in the analysis of nephrology data