LOS ANGELES – Women, as well as all patients aged 65 years or older who have substantial carotid artery stenosis that needs revascularization, may prefer endarterectomy, and would want to steer clear of carotid stenting, according to new data from CREST, the largest randomized trial to compare these two carotid interventions.
Dr. George Howard
All patients aged 65 or older who were randomized to treatment by carotid artery stenting had a statistically significant excess of strokes, compared with similar subgroups who were treated with endarterectomy during the periprocedural period and 4-year follow-up, George Howard, Dr.P.H., said at the International Stroke Conference. "Patient age should be an important factor in selecting the treatment option for carotid stenosis," said Dr. Howard, professor and chairman of biostatistics at the University of Alabama at Birmingham.
Analysis of the patients enrolled in CREST (Carotid Revascularization Endarterectomy vs. Stenting Trial) by sex showed that the treatment of carotid stenosis by stenting led to an excess rate of periprocedural strokes among women, but not in men, Virginia J. Howard, Ph.D., said in a separate talk at the conference. Women who underwent an endarterectomy also had no excess risk for myocardial infarctions, compared with women who received a carotid stent, unlike men who had a significantly increased rate of MIs following open surgery, compared with those who got stented, said Dr. Howard, an epidemiologist at the University of Alabama at Birmingham.
The primary results from CREST, first reported last year, showed that all patients who were enrolled in the study had similar rates of stroke, MI, or death regardless of whether they underwent carotid endarterectomy or stenting (N. Engl. J. Med. 2010;363:11-23). But these new details, which show an excess rate of periprocedural strokes in women undergoing stenting as well as the excess of all strokes in patients aged 65 or older undergoing stenting, may tip the balance away from stenting in these patient subgroups.
Another CREST analysis that was also reported at the conference showed that patients who had a stroke had significant decrements in several measures of their health status at 1 year following their intervention, whereas patients who had an MI generally had a much more average health status profile after 1 year.
Going into CREST, which began in 2000, "we thought the results would be the opposite. [At that time,] we preferred to take older patients to stenting," commented Dr. Thomas G. Brott, lead investigator for CREST and a professor of neurology and director or research at the Mayo Clinic in Jacksonville, Florida. "Our interventionalists believe that age is a surrogate marker for patients with calcified and tortuous vessels that might not be suitable for stenting." Regarding the sex-related finding, the implications "depend on how a woman would value [the risk of having] a stroke or a MI. If the woman is more concerned about a periprocedural stroke, then the results suggest there could be a preference for endarterectomy," Dr. Brott said in an interview.
In the sex-based analysis, the rate of periprocedural stroke was 5.5% in stented women and 2.2% in those who underwent endarterectomy, a statistically significant 2.6-fold increased rate with stenting, Dr. Virginia Howard reported. During the entire follow-up, which added the rate of ipsilateral strokes during 4 years following the intervention, stroke rates were 7.8% in stented women and 5.0% in those who had endarterectomy, a nonsignificant difference. The two treatment options produced no difference in stroke rates in men, either periprocedurally or after 4 years. MI rates were similar in women following either intervention, both periprocedurally and after 4 years. The periprocedural and 4-year MI rates in men were significantly higher with endarterectomy.
In the age-based analyses, a calculation that used age as a continuous variable showed that the number of strokes occurring with either endarterectomy or stenting was similar for patients aged 64 years. For those aged 65 or older, fewer strokes occurred with endarterectomy, a relationship that grew stronger with increasing age. For patients aged 63 or younger, stenting produced fewer strokes, and the relationship grew stronger with decreasing age.
The age analysis also examined the data by dividing patients into three prespecified age group: younger than 65, 65-74 years, and 75 and older. (See box.) The most striking age effect occurred in patients aged 75 or older: In this subgroup, treatment with stenting more than doubled the total stroke risk, both periprocedural and long-term strokes, compared with patients who were treated with endarterectomy.
The incidence of MI showed a much weaker age effect, and patients who underwent stenting had a reduced rate of MI at all ages, compared with those who had endarterectomy. In addition, in the endarterectomy arm, age had no significant effect on the MI rate. Among patients treated with endarterectomy, the incidence of MI was 1.6% in patients younger than 65 years and 3.2% in those aged 75 or older, differences that were not statistically significant, Dr. George Howard said.