ICD-10 adaptations of the Ontario acute myocardial infarction mortality prediction rules performed as well as the original versions.
OBJECTIVE
To derive and validate an International Classification of Diseases-10 (ICD-10) version of the Ontario Acute Myocardial Infarction (AMI) mortality prediction rules, used to adjust for case-mix differences in studies of AMI patients using administrative data.


METHODS
We linked the records of all Ontario patients admitted with AMI (2002-2004) with mortality data. The original ICD-9 codes were mapped to ICD-10-CA (Canada) codes using both a translation produced by coding experts and a manual search of codes; the final codes were determined by consensus. Comorbidity prevalence and mortality rates were calculated. Multivariable logistic regression models were used to predict 30-day and 1-year mortality and the C-statistic was used to evaluate the discrimination of the models.


RESULTS
We identified 37,271 AMI patients. The most common comorbidities were heart failure and dysrhythmias; 30-day and 1-year mortality rates were 12.3% and 21.8%, respectively; and mortality rates were highest among patients with shock, cancer, and acute renal failure. The C-statistics were 0.77 and 0.80, compared with 0.78 and 0.79 in the ICD-9 version, for 30-day and 1-year mortality, respectively.


CONCLUSIONS
An ICD-10 version of the AMI mortality prediction rules predicted 30-day and 1-year mortality as well as the original ICD-9 version.
Vermeulen
Marian J
MJ
Institute for Clinical Evaluative Sciences, Department of Health Policy, Management and Evaluation, University of Toronto, Ontario, Canada.
Tu
Jack V
JV
Schull
Michael J
MJ
D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D002170:Canada / Q000453:epidemiology; D015897:Comorbidity; D005260:Female; D006801:Humans; D038801:International Classification of Diseases; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000401:mortality*; D011379:Prognosis; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors