European Analysis Compares CAS and CEA in Older Patients

September 10, 2010—Professor Martin M. Brown, MD, et al, for the Carotid Stenting Trialists' Collaboration in Europe, published a preplanned meta-analysis of individual patient data to compare short-term outcomes after CAS versus CEA for symptomatic carotid stenosis. The investigators concluded that CAS might be as safe as CEA in younger patients (age < 70 years) but should be avoided in older patients (age ≥ 70 years) with symptomatic carotid stenosis. The findings were published online ahead of print in The Lancet.

According to the investigators, results from randomized controlled trials have shown a higher short-term risk of stroke associated with CAS than with CEA for treating symptomatic carotid stenosis. However, these trials were underpowered for investigation of whether CAS might be a safe alternative to CEA in specific patient subgroups.

Therefore, the investigators conducted this preplanned meta-analysis of individual patient data from three randomized controlled trials: EVA-3S (Endarterectomy Versus Angioplasty in Patients With Symptomatic Severe Carotid Stenosis), SPACE (Stent-Protected Angioplasty Versus Carotid Endarterectomy), and ICSS (International Carotid Stenting Study).

As detailed in The Lancet, data from all 3,433 patients with symptomatic carotid stenosis who were randomly assigned and analyzed in EVA-3S, SPACE, and ICSS were pooled and analyzed with fixed-effect binomial regression models adjusted for the source trial. The primary outcome event was any stroke or death. The intention-to-treat (ITT) analysis included all patients and outcome events occurring between randomization and 120 days thereafter. The per-protocol (PP) analysis was restricted to patients receiving the allocated treatment and events occurring within 30 days after treatment.

In the first 120 days after randomization (ITT analysis), any stroke or death occurred significantly more often in the CAS group (153 of 1,725) than in the CEA group (99 of 1,708) (8.9% vs 5.8%; risk ratio [RR], 1.53, [95% confidence interval [CI], 1.2–1.95]; P = .0006; absolute risk difference, 3.2 [1.4–4.9]).

Of all subgroup variables assessed, only age significantly modified the treatment effect: in patients younger than 70 years (median age), the estimated 120-day risk of stroke or death was 5.8% in the CAS group (50 of 869 patients) and 5.7% in the CEA group (48 of 843 patients) (RR, 1 [0.68–1.47]). In patients 70 years or older, the estimated risk with CAS (103 of 856 patients) was twice that with CEA (51 of 865 patients) (12% vs 5.9%; RR, 2.04 [1.48–2.82]; interaction P = .0053, P = .0014 for trend).

In the PP analysis, risk estimates of stroke or death within 30 days of treatment among patients younger than 70 years were 5.1% (43 of 851 patients) in the CAS group and 4.5% (37 of 821 patients) in the CEA group (RR, 1.11 [0.73–1.71]); in patients 70 years or older, the estimates were 10.5% (87 of 828 patients) and 4.4% (36 of 824), respectively (RR, 2.41 [1.65–3.51]; categorical interaction, P = .0078; trend interaction, P = .0013), the investigators reported.