Risk of Inhospital Stroke or Death Is Associated With Age But Not Sex in Patients Treated With Carotid Endarterectomy for Asymptomatic or Symptomatic Stenosis in Routine Practice: Secondary Data Analysis of the Nationwide German Statutory Quality Assurance Database From 2009 to 2014

Abstract

Background: Guideline recommendations on carotid endarterectomy are based predominantly on randomized, controlled trials, in which women or elderly patients are often under-represented. This study analyzed the association of age and sex with the risk of in-hospital stroke or death following carotid endarterectomy under routine conditions in Germany.

Methods and results: Secondary data analysis using the Statutory German Quality Assurance Database on all carotid endarterectomy procedures (n=142 074) performed between 2009 and 2014. Primary outcome was any stroke or death until discharge; secondary outcomes were any in-hospital stroke (alone), and death (alone). Descriptive statistics and multilevel multivariable regression analyses were applied. Patients were predominately male (68%), with mean age 71 years. Carotid stenosis was symptomatic in 40%. Primary outcome occurred in 1.8% of women and 1.9% of men. Multivariable regression analysis revealed that more-advanced age was associated with a higher primary outcome rate (relative risk [RR] per 10-year increase: 1.19; 95% CI, 1.14-1.24). Risk of death (alone) was associated with age (RR, 1.68; 95% CI, 1.54-1.84). Age was associated with the risk of stroke (alone; RR, 1.05; 95% CI, 1.00-1.11). Sex was not associated with primary outcome rate (1.01; 95% CI, 0.93-1.10), nor did it significantly modify the age effect.

Conclusions: This study shows that increasing age, but not sex, is associated with a higher risk of in-hospital stroke or death following carotid endarterectomy under everyday conditions in Germany. Whereas the risk of death (alone) is significantly associated with age, the association between age and the risk of stroke (alone) can be considered of minor importance.

Keywords: aging; carotid artery; sex; stenosis; surgery.

Figure 1

Patient selection. CAS indicates carotid artery stenting; CEA, carotid endarterectomy; ICA, internal carotid artery; PTA, percutaneous transluminal angioplasty; TIA, transient ischemic attack.

Figure 2

Crude risk of (A) any in‐hospital stroke or death, (B) stroke alone, and (C) death alone by age groups and neurological status on admission (left). Sex‐specific rates are depicted in the right column (see Table 3 for point estimates and 95% CIs; see Figure 3 for adjusted risk ratios and CIs). A indicates asymptomatic ICA stenosis; bars, 95% CI; CEA, carotid endarterectomy; ICA, internal carotid artery; S, symptomatic ICA stenosis (nonemergency).

Figure 3

Forest plot of multilevel multivariable regression results. Association of age and sex with the in‐hospital risk of (A) any stroke or death, (B) any stroke alone, and (C) all‐cause death alone. Adj. RR=risk ratio adjusted for ASA category, neurological status on admission, ipsi‐ and contralateral degree of carotid stenosis, antiplatelet medication, pre‐ and postoperative assessment by a neurologist, intraoperative neurophysiological monitoring, technique of CEA, anesthesia, shunting, intraoperative check of technical success, clamping time, and annual hospital CEA volume (see Methods for further details on the regression model); bars indicate 95% CI. ASA indicates American Society of Anesthesiologists; CEA, carotid endarterectomy.

Figure 4

Relative risks as a function of age for (A) any in‐hospital stroke or death, (B) any stroke, and (C) all‐cause death alone (please note differing range of the y‐axis). Dotted lines indicate the 95% CI. CEA indicates carotid endarterectomy; m, men; w, women.