Impact of obesity on results after primary angioplasty in patients with ST segment elevation acute myocardial infarction.
BACKGROUND
Obesity is an important risk factor for the development of diabetes, hypertension, coronary disease, left ventricular dysfunction, stroke and cardiac arrhythmias. Paradoxically, previous studies in patients undergoing elective coronary angioplasty showed a reduction in hospital and long-term mortality in obese patients. The relation with body mass index (BMI) has been less studied in the context of primary angioplasty.


OBJECTIVE
To evaluate the impact of obesity on the results of ST-segment elevation acute myocardial infarction treated by primary angioplasty.


METHODS
This was a study of 464 consecutive patients with ST-segment elevation acute myocardial infarction undergoing primary angioplasty, 78% male, mean age 61 +/- 13 years. We assessed in-hospital, 30-day and one-year mortality according to BMI. Patients were divided into three groups according to BMI: normal--18-24.9 kg/m2 (n = 171); overweight--25-29.9 kg/m2 (n = 204); and obese-- > 30 kg/m2 (n = 89).


RESULTS
Obese patients were younger (ANOVA, p < 0.001) and more frequently male (p = 0.014), with more hypertension (p = 0.001) and dyslipidemia (p = 0.006). There were no differences in the prevalence of diabetes, previous cardiac history, heart failure on admission, anterior location, multivessel disease, peak total CK or medication prescribed, except that obese patients received more beta-blockers (p = 0.049). In-hospital mortality was 9.9% for patients with normal BMI, 3.4% for overweight patients and 6.7% for obese patients (p = 0.038). Mortality at 30 days was 11 4.4% and 7.8% (p = 0.032) and at one year 12.9%, 4.9% and 9% (p = 0.023), respectively. On univariate analysis, overweight was the only BMI category with a protective effect; however, after multivariate logistic regression analysis, adjusted for confounding variables, none of the BMI categories could independently predict outcome.


CONCLUSIONS
Overweight patients had a better prognosis after primary angioplasty for ST-segment elevation acute myocardial infarction compared with other BMI categories, but this was dependent on other potentially confounding variables.
Serviço de Cardiologia, Hospital de Santa Marta, Centro Hospitalar de Lisboa Central EPE, Lisboa. ana_timoteo@yahoo.com
Ana Teresa
AT
Timóteo
Ruben
R
Ramos
Alexandra
A
Toste
José Alberto
JA
Oliveira
Lino
L
Patrício
Maria Lurdes
ML
Ferreira
Rui Cruz
RC
Ferreira
D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications* / Q000503:physiopathology / Q000601:surgery*; D009765:Obesity / Q000150:complications*; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome