Effect of beta-blockers on the mortality of Japanese patients with myocardial infarction.
BACKGROUND
After a myocardial infarction, a higher prevalence of coronary vasospastic response has been reported in the Japanese population than in the Caucasian population. Beta-blockers may exacerbate coronary vasospasm. However, beta-blockers are given to Japanese patients after an acute myocardial infarction, though the mortality benefit is unknown. Thus, we investigated the mortality benefit of beta-blockers given to Japanese patients after an acute myocardial infarction.


METHODS
We prospectively studied consecutive patients with a first myocardial infarction admitted to the coronary care unit of Kansai Medical University Hospital, Osaka, Japan from May 1994 through the end of 2001. Patients who died during hospitalization or who were referred for coronary artery bypass graft surgery were excluded. The association of beta-blocker use with mortality after discharge was assessed by a proportional hazards regression analysis.


RESULTS
There were 546 patients and 400 (73.3%) patients were treated with beta-blockers at the time of discharge from hospital. During a mean follow-up of 2 years, 46 (8.4%) patients died. Beta-blocker therapy was associated with a reduced mortality after adjustment for age, gender, Q wave myocardial infarction, reperfusion therapy during acute phase, Killip functional class, serum creatinine level, cardiovascular risk factors, and medications (hazard ratio=0.51, 95% confidence interval=0.27 to 0.95).


CONCLUSIONS
Contrary to the concern that beta-blocker therapy might induce coronary vasospasm and reduce survival, beta-blocker therapy improved survival after discharge in Japanese patients with a first myocardial infarction.
Yamada
Koichi
K
Cardiovascular Center, Kansai Medical University, Moriguchi, Japan.
Tsuji
Hisako
H
Tokunaga
Satoshi
S
Kurimoto
Koji
K
Maeba
Hirofumi
H
Matsuhisa
Seiji
S
Inami
Norihito
N
Iwasaka
Toshiji
T
D000319:Adrenergic beta-Antagonists / Q000009:adverse effects / Q000627:therapeutic use*; D000368:Aged; D017023:Coronary Angiography; D003329:Coronary Vasospasm / Q000139:chemically induced; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000401:mortality*; D011446:Prospective Studies; D012307:Risk Factors; D016019:Survival Analysis
D000319:Adrenergic beta-Antagonists