Correlation of rates of coronary artery bypass surgery, angioplasty, and cardiac catheterization in 305 large communities for persons age 65 and older.
OBJECTIVE
The rate of coronary artery bypass surgery (CABG) has been shown to vary greatly across geographic regions. This study examined whether these rates were associated with the rate of coronary artery angioplasty (PTCA) and with other community characteristics.


METHODS
The health care financing administration provided the number of Medicare hospitalizations in 1988 for conditions and procedures related to coronary artery disease. Information on physicians and hospitals was obtained from the Area Resource File, and the number of persons in each age, sex, and race category was obtained from US. census data.


METHODS
Age-and sex-adjusted hospitalization rates based on the patient's zip code of residence were calculated at the level of the Metropolitan Statistical Area (MSA) for white patients age 65 or older. Rates were obtained for 305 MSAs for CABG, PTCA, cardiac catheterization, angina, and myocardial infarction.


RESULTS
The rate of cardiac catheterization had a correlation of .72 with the CABG rate and .64 with the PTCA rate. The correlation of the PTCA and CABG rates with each other was .49. This correlation was not charged by adjusting for the rates of hospitalization for angina or myocardial infection, but it was reduced to only .05 (ns) after adjusting for the rate of cardiac catheterization. The rates of all three procedures had rank correlations of about .15 with the density of thoracic surgeons and about .30 with the density of hospitals with cardiac catheterization and open heart surgery units.


CONCLUSIONS
Community CABG and PTCA rates tend to move in the same direction due to community factors that also affect the rates of cardiac catheterization. These community factors do not appear to include the rate of coronary artery disease, but may include resources or attitudes toward aggressive treatment of coronary artery disease.
Kuhn
E M
EM
Medical College of Wisconsin, Milwaukee 53226, USA.
Hartz
A J
AJ
Baras
M
M
D000368:Aged; D000369:Aged, 80 and over; D015906:Angioplasty, Balloon, Coronary / Q000706:statistics & numerical data*; D006328:Cardiac Catheterization / Q000706:statistics & numerical data*; D014487:Centers for Medicare and Medicaid Services, U.S.; D001026:Coronary Artery Bypass / Q000706:statistics & numerical data*; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D006278:Medicare; D012044:Regression Analysis; D017062:Small-Area Analysis; D018709:Statistics, Nonparametric; D014481:United States / Q000453:epidemiology