Renal dysfunction as a risk factor for painless myocardial infarction: results from Korea Acute Myocardial Infarction...

Renal dysfunction has been associated with many types of neuropathy and the incidence of myocardial infarction (MI) presenting without chest pain can be expected to be higher in patients with renal dysfunction. We evaluated clinical outcomes of painless MI patients and relationship between renal dysfunction and painless MI.

Study population consisted of 9,735 patients (63 ± 13 years, men 70.7 %), whose discharge diagnosis by cardiac enzyme and electrocardiogram was MI. The study subjects were divided into two groups according to presence of chest pain (painful MI group, n = 8,249; painless MI group, n = 1486). Rates of in-hospital death, 1-month and 12-month composite MACE, cardiac death, and non-cardiac death were significantly higher in painless MI patients. In a multivariate logistic analysis, compared with glomerular filtration rate (GFR) > 90 mL/min/1.73 m(2), odds ratio of painless MI was increased proportionally in patients with GFR of 30-59, 15-29 and <15 mL/min/1.73 m(2) (odds ratio [OR] 1.25, 95 % confidence interval [CI] 1.05-1.49; OR 1.88, CI 1.39-2.53; OR 2.32, CI 1.65-3.26) In addition, the concomitant presence of renal dysfunction and diabetes mellitus significantly affected the prevalence of painless MI.

Poorer outcomes of painless MI patients and the increased probability of painless MI proportional to declining GFR indicate that the possibility of painless MI should be considered in patients with renal dysfunction, particularly concomitant with diabetes mellitus.