Clinical Grading Scales in Spontaneous Intracerebral Hemorrhage
To the Editor:
We have had the pleasure to read the article by Dr Ruiz-Sandoval and colleagues,1 regarding the development of a new spontaneous intracerebral hemorrhage (sICH) grading scale, formally called ICH-GS, for the prediction of outcome after primary sICH. In comparison with other cerebrovascular diseases, there are no grading prognostic scales routinely used in sICH around the world. Any effort is welcome to develop simple and reproducible scales in predicting sICH outcome.
The ICH-GS was generated using the same variables used in original (o)-ICH score by Hemphill and colleagues2 using different grading system, score punctuation and introducing a new variable (Table 1). The ICH-GS seems to show a higher sensitivity in predicting 30-day mortality and good functional outcome when compared with oICH score.1
Previously, we validated in a cohort of 153 sICH patients the oICH score against 2 modified scores (mICH), score -A and score -B, respectively, with the same variables than oICH score, except localization, with different cutoff values (Table 1).3 In our socially and culturally different cohort, oICH score confirmed its validity and modifications of oICH did not improve its 30-day mortality prediction but improved its ability to predict good functional outcome at 6 months.3 This higher prediction ability was more evident for our mICH-B score.3 From this standpoint, we validated ICH-GS score in our sICH cohort in prediction of 30-day mortality and, as secondary end point, its 6-month functional outcome prediction. To establish the predictive value of the oICH, ICH-GS and mICH-B scores on mortality and functional outcome, the area under the receiver operating characteristic curves were directly calculated by a nonparametric method for each ICH score. CIs were constructed using DeLong variance estimate. Different cutoff values of the oICH, mICH-B and ICH-GS scores were used to identify the best Youden index of diagnostic test for a comparison among the different ICH scores. The sensitivity, specificity, positive predictive value, and negative predictive value of different ICH scores were computed using the cutoff values that generated the best Youden index.
Both oICH (P=0.0167; DeLong variance estimate) and mICH-B score (P=0.0039) showed a better 30-day mortality prediction when compared with ICH-GS score (Figure, a). Furthermore, mICH-B score showed a better prediction of functional outcome at 6 months when compared with the oICH score (P=0.0314) and the ICH-GS score (P=0.0023; Figure, b). In Table 2 prognostic performance of compared ICH scores are given. All ICH scores were substantially equally sensitive with a high negative predictive value for mortality, whereas mICH-B score was more specific, with a high positive predictive value for good outcome (Table 2). According to Youden index, the oICH and mICH-B scores were reliable predictors for mortality, whereas ICH-GS was less reliable in predicting this one. The mICH-B score was better for predicting good outcome than the oICH and ICH-GS scores (Table 2).
In conclusion, we were unable to confirm the superiority of ICH-GS score in a similar Latin American population when compared with the oICH in predicting mortality. The oICH score remains a good predictor of 30-day mortality and functional outcome at 6 months. The inclusion of variables not included in oICH or different grading of the same variables does not significantly improve mortality prediction although it seems to have a better prediction of good functional outcome. All 3 compared ICH scores are simple clinical grading scales; the mICH-B score may be preferred when good outcome is the primary target, and as reliable predictor of mortality and/or good outcome. It could be useful in clinical research studies and standardization of clinical protocols. Our proposal is that the mICH-B score should be tested and validated in different populations and against different grading scales to verify its validity in prognosis prediction. In the future, only with collaborative efforts the scientific community will be able to have a useful instrument in the prognostic stratification of sICH patients, improving the quality of their care.
Ruiz-Sandoval JL, Chiquete E, Romero-Vargas S, Padilla-Martínez JJ, González-Cornejo S. Grading Scale for prediction of outcome in primary intracerebral hemorrhages. Stroke. 2007; 38: 1641–1644.
Hemphill JC III, Bonovich DC, Besmertis L, Manley GT, Johnston SC. The ICH score: a simple, reliable grading scale for intracerebral hemorrhage. Stroke. 2001; 32: 891–897.
Godoy DA, Pinero G, Di Napoli M. Predicting mortality in spontaneous intracerebral hemorrhage: can modification to original score improve the prediction? Stroke. 2006; 37: 1038–1044.