Comorbidity adjustment index for the international classification of diseases, 10

Abstract

METHODS:Clinical conditions and weights were adapted from the International Classifi cation of Diseases, 10th revision and applied to a single hospital admission diagnosis. The study included 3,733 patients over 18 years of age who were admitted to a public general hospital in the city of Rio de Janeiro, southeast Brazil, between Jan 2001 and Jan 2003. The index distribution was analyzed by gender, type of admission, blood transfusion, intensive care unit admission, age and length of hospital stay. Two logistic regression models were developed to predict in-hospital mortality including: a) the aforementioned variables and the risk-adjustment index (full model); and b) the risk-adjustment index and patient's age (reduced model). RESULTS:Of all patients analyzed, 22.3% had risk scores ≥1, and their mortality rate was 4.5% (66.0% of them had scores ≥1). Except for gender and type of admission, all variables were retained in the logistic regression. The models including the developed risk index had an area under the receiver operating characteristic curve of 0.86 (full model), and 0.76 (reduced model). Each unit increase in the risk score was associated with nearly 50% increase in the odds of in-hospital death. CONCLUSIONS:The risk index developed was able to effectively discriminate the odds of in-hospital death which can be useful when limited information is available from hospital databases. Hospital administrative databases are frequently used for estimating clinical or epidemiological empirical models and these models should consider, as much as possible, the inclusion of variables controlling for patients' health status. These variables, known as risk-adjustment indexes, 21 are also useful for predicting patient outcome (e.g., mortality) in a variety of settings. 4 One of these indexes is the Charlson Comorbidity Index, 3 which essentially classifi es patients by weighting the severity of their clinical conditions. The Charlson index was originally proposed for longitudinal mortality studies, but there is evidence of its validity in a large number of clinical situations. 7,8 Although the most recent (10 th ) revision of the International Classifi cation of Diseases (ICD) has been available for more than ten years, a applications of the Charlson index are frequently based on standardized coding of co-morbidities according to the ICD, 9 th revision (ICD-9). 13 In addition, the number of conditions to be weighed for a sensitive RESUMO OBJETIVO: Desenvolver um índice de co-morbidade a partir das condições clínicas e dos pesos do índice de co-morbidade de Charlson. DESCRIPTORS MÉTODOS:As condições clínicas e pesos do índice de Charlson foram adaptados segundo a Classifi cação Internacional de Doenças -10 a Revisão, e aplicados ao diagnóstico principal de internação hospitalar. Foram estudados 3.733 pacientes acima de 18 anos hospitalizados em hospital geral público do município do Rio de Janeiro, RJ, 2001RJ, -2003. A distribuição do índice foi de acordo com o gênero, tipo da admissão, presença de transfusão de san...

Drug-Drug Interactions Associated with Length of Stay and Cost of Hospitalization

“…Clinical conditions were classified with a modified version of the Charlson Comorbidity Index (CCI) on the basis of hospital discharge International Classification Disease 10 th version (ICD-10) codes. This Charlson-like index uses a single hospital diagnosis based on ICD-10 for risk adjustment (13). The modified CCI was dichotomized (low morbidity = 0, high = 1).…”

Fatores associados à chance para a mortalidade hospitalar no Distrito Federal

“…Por exemplo, o índice Charlson, 15 da mesma forma que outros índices semelhantes de ajustes de co-morbidades, 16 poderia ter auxiliado na melhor discriminação dos fatores associados à chance de óbito hospitalar e melhor ajuste para a gravidade da causa da internação. Além disso, não se pode descartar a possibilidade de erros (intencionais ou não) referentes às causas de internação e às causas básicas dos óbitos.…”

Interação medicamentosa associada à reinternação hospitalar: estudo retrospectivo em um hospital geral

“…CCI, in the way it was used in this study, gives much more perspective to the seriousness of the reason for admission than the weight of the patient's comorbidities. The adaptation proposed by Ramiarina et al 22 performs satisfactorily in adjusting the seriousness in the HIS/SUS database, especially in the analysis of the cost of the hospital stay. However, there were limitations in the use of this index for evaluating some outcomes, mainly because the majority of HAAs did not contain information on secondary diagnoses.…”

“…This restriction was observed in the records used in this study, and also in other studies. 13,22 The main limitations of this study, described above, are related to its retrospective design and the use of secondary databases. Together, these characteristics limit the collection of other important data and may have introduced bias in selection and information.…”