A study of some clinical variables in predicting outcome after acute myocardial infarction

The univariate analysis of age, previous myocardial infarction, systolic blood pressure, diabetes, smoking, etc, accounted their association with increased mortality in acute myocardial infarction (AMI). Thus, the study was undertaken to determine the significance of some such variables among hospitalised AMI cases by applying univariate statistical techniques. Two years retrospective data of 208 hospitalised AMI cases was collected from patients' records. Impact of each study variable on outcome, survival and non-survival, was assessed by Student's 't' test while association between risk factor and outcome was estimated by Chi-square test. Twenty-five per cent of non-survival was observed in AMI cases. Non-survival was high among those, whose age was more than 60 years (t = 4.37, p < 0.001) and who were village dwellers (t = 3.69, p < 0.001). The non-survival in previous myocardial Infarction (MI) and diabetes cases was 28% and 30% respectively. Thirty per cent of cases with previous MI and hypertension together as common risk factors did not survive. On admission significantly low systolic blood pressure (t = 3.23, p < 0.01), high pulse rate (t = 4.88, p < 0.001) and high blood sugar (t = 2.55, p < 0.05) was observed among non-survivals. There was large variation in explaining survival/non-survival on the basis of each variable, separately. Involvement of single variable in determination of prognosis assuming non-influence of other variable(s), may result in improper determination of prognosis.