Survival benefit from calcium channel blockers in elderly blacks following acute myocardial infarction.
BACKGROUND
Calcium channel blockers (CCBs) have been used in elderly survivors of acute myocardial infarctions (AMI) and have been found to be safe in this setting. While the elderly have increased mortality following AMI, an ethnic disparity exists, with elderly African Americans having the highest mortality. It is proposed that much of the increased mortality in elderly African Americans may be related to their greater incidence of risk factors at the time of AMI, particularly hypertension. We proposed that elderly African Americans would receive survival benefits from the blood pressure lowering effects of CCBs.


METHODS
We analyzed the Cooperative Cardiovascular Project (CCP) database to evaluate the impact of CCBs on survival in elderly patients with AMI. This database comprises patients admitted to US hospitals during 1994-1995 with a diagnosis of acute myocardial infarction. A retrospective chart analysis was performed to identify patients aged 65 years or older admitted with ICD-9 code 410 for acute myocardial infarction. Data were analyzed for trends.


RESULTS
Of all elderly AMI admissions, 144,233 were Whites, and 9,906 were Blacks. Hypertension was common in both Whites and Blacks, 60.4% and 79.1%, P<.001, respectively. Calcium channel blockers were used with 27.3% of Whites, and 31.2% of Blacks, P<.001. Blacks had a lower 2-year survival rate, regardless of CCB status, with a 55.7% 2-year survival rate, compared to a 51% 2-year survival rate in Whites. However, in both Blacks and Whites, 2-year survival improved with CCB treatment to a 71.2% 2-year survival rate in Whites and a 68.5% 2-year survival rate in Blacks. Subset analysis by type of CCB demonstrated better survival rates with both dihydropyridine and non-dihydropyridine CCBs, compared to no CCBs, although there was a survival trend favoring non-dihydropyridine CCBs.


CONCLUSIONS
Elderly Blacks had a higher mortality rate in the CCP database than elderly Whites, at each time frame. Calcium channel blocker therapy was associated with improved survival in both Whites and Blacks, although Blacks continued to have lower survival rates with CCBs when compared with Whites.
Williams
Deborah
D
Howard University College of Medicine, Washington, DC, USA. dwilliams@fac.howard.edu
Kim
Kyung Sook
KS
Adams-Campbell
Lucile L
LL
D001741:Black or African American; D000368:Aged; D002121:Calcium Channel Blockers / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000188:drug therapy* / Q000208:ethnology / Q000401:mortality*; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D016019:Survival Analysis
D002121:Calcium Channel Blockers