Background A recent randomized trial of patients with primarily anterior circulation intracranial artery stenosis showed that intensive medical therapy was superior to intracranial stenting in preventing recurrent stroke. The rate of stroke recurrence or death in symptomatic intracranial vertebrobasilar stenosis with medical therapy alone may be especially high, and rates compared with endovascular therapy need further study.

Methods We conducted a systematic review and meta-analysis of studies reporting the rates of stroke recurrence or death (the primary outcome) in symptomatic intracranial vertebrobasilar stenosis with medical or endovascular treatment over a minimum follow-up period of 6 months. We included all studies in any language indexed in MEDLINE or EMBASE, supplemented by bibliography searches and by contacting the authors. The secondary endpoints were stroke recurrence, and basilar artery and vertebral artery stroke recurrence rates.

Results 23 studies (592 medical treatment patients and 480 endovascular treatment patients) were included. The risk of combined stroke recurrence or death was 14.8 per 100 person-years (95% CI 9.5 to 20.1) in the medical group compared with 8.9 per 100 person-years (95% CI 6.9 to 11.0) in the endovascular group. The incidence rate ratio was 1.3 (95% CI 1.0 to 1.7). The stroke recurrence rate was 9.6 per 100 person-years (95% CI 5.1 to 14.1) in the medical group compared with 7.2 per 100 person-years (95% CI 5.5 to 9.0) in the endovascular group.

Conclusions Our results showed that the risk of stroke recurrence or death or the risk of stroke recurrence alone was comparable between the medical and endovascular therapy groups. A small preventive effect of endovascular therapy may exist, particularly if the 30 day postprocedural risk is reduced.