Table 2.

Two-year risks for outcomes by treatment and CKD status (eGFR, ml/min per 1.73 m²) in patients with high-grade internal carotid artery stenosis (70 to 99%)

Parameter	Medical Risk (%)(n = 126)^a(n = 197)^b	Surgical Risk (%)(n = 91)^a(n = 233)^b	RRR (%)	Absolute Risk Difference (%; 95% CI)	P	Interaction Test (P)
Parameter	Medical Risk (%)(n = 126)^a(n = 197)^b	Surgical Risk (%)(n = 91)^a(n = 233)^b	RRR (%)	Absolute Risk Difference (%; 95% CI)	P	Risk Difference	RRR
Ipsilateral stroke^c
eGFR <60	31.6	5.6	82.3	26.0 (15.1 to 36.8)	<0.001	0.018	0.051
eGFR ≥60	19.3	9.5	50.8	9.8 (1.9 to 17.7)	0.047
Death (any cause)
eGFR <60	9.4	9.7	−3.2	−0.3 (−11.1 to 10.5)	0.94	0.83	0.78
eGFR ≥60	5.9	4.9	16.9	1.0 (−4.4 to 6.4)	0.59
Any stroke, MI, or vascular death
eGFR <60	40.7	17.5	57.0	23.2 (9.6 to 36.7)	0.016	0.07	0.26
eGFR ≥60	23.0	15.0	34.8	8.0 (−1.0 to 17.0)	0.13

Medical and surgical groups were compared using a log-rank test. RRR, relative risk reduction.
↵^aeGFR <60 ml/min per 1.73 m².
↵^beGFR ≥60 ml/min per 1.73 m².
↵^cTo provide a more conservative estimate of the benefits of endarterectomy, the outcome “ipsilateral stroke” includes any stroke and any death within 32 d of randomization (30 d postoperatively; median time from randomization to surgery was 2 d).