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Epidemiology of carotid endarterectomy and cerebral arteriography in the United States.

BACKGROUND AND PURPOSE
Results of North American and European trials of carotid endarterectomy published in 1991 may have affected the frequency of the procedure in the United States. Therefore, data from a national survey of hospital discharges were examined to determine whether rates of carotid endarterectomy and arteriography increased after 1991 and whether race and sex variations in rates have persisted.


METHODS
Data from the National Hospital Discharge Survey were examined for the years 1980 through 1993. Estimated numbers of procedures performed in nonfederal US hospitals were used to compute rates per 100,000 population by year, age, race, and sex.


RESULTS
In persons aged 65 years and over, the rate of carotid endarterectomy increased rapidly between 1980 and 1983 with a slight further increase through 1985. A marked fall in the rate occurred between 1985 and 1988, followed by a plateau and a sharp upturn in 1992. After 1985, there was a steady decline in the rate of cerebral arteriography procedures in hospital. No reliable data were available on outpatient cerebral arteriography. Throughout the period, whites had estimated rates of carotid endarterectomy procedures over four times higher than blacks. Whites also had higher rates of cerebral arteriography, but the disparity was not as great as for endarterectomy. Rates of carotid endarterectomy were 60% higher in men than women, but rates of cerebral arteriography were only 9% higher in men than women.


CONCLUSIONS
Rates of carotid endarterectomy increased sharply after the 1991 publication of trial results. Marked racial disparities in the use of this procedure persist and require further evaluation.