[Risk stratification of patients with diabetes mellitus undergoing coronary artery bypass grafting--a comparison of statistical methods].
Among the coronary bypass patients from our Datamart database, we found a prevalence of 29.6% of diagnosed diabetics. 5.2% of the patients without a diagnosis of diabetes mellitus and a fasting plasma glucose level > 125 mg/dl were defined as undiagnosed diabetics. The objective of this paper was to compare univariate methods and techniques for risk stratification to determine, whether undiagnosed diabetes is per se a risk factor for increased ventilation time and length of ICU stay, and for increased prevalence of resuscitation, reintubation and 30-d mortality for diabetics in heart surgery. Univariate comparisons reveals that undiagnosed diabetics needed resuscitation significantly more often and had an increased ventilation time, while the length of ICU stay was significantly reduced. The significantly different distribution between the diabetics groups of 11 from 32 attributes examined, demands the use of methods for risk stratification. Both risk adjusted methods regression and matching confirm that undiagnosed diabetics had an increased ventilation time and an increased prevalence of resuscitation, while the length of ICU stay was not significantly reduced. A homogeneous distribution of the patient characteristics in the two diabetics groups could be achieved through a statistical matching method using the propensity score. In contrast to the regression analysis, a significantly increased prevalence of reintubation in undiagnosed diabetics was found. Based on an example of undiagnosed diabetics in heart surgery, the presented study reveals the necessity and the possibilities of techniques for risk stratification in retrospective analysis and shows how the potential of data collection from daily clinical practice can be used in an effective way.
Arnrich
B
B
AG Neuroinformatik, Universität Bielefeld, 33501 Bielefeld.
Albert
A
A
Walter
J
J
D001026:Coronary Artery Bypass / Q000401:mortality; D003627:Data Interpretation, Statistical; D016208:Databases, Factual; D048909:Diabetes Complications; D003920:Diabetes Mellitus / Q000175:diagnosis* / Q000453:epidemiology; D006801:Humans; D007362:Intensive Care Units; D007902:Length of Stay; D015995:Prevalence; D012044:Regression Analysis; D012121:Respiration, Artificial; D012151:Resuscitation; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors