Recommencement of anticoagulation in chronic subdural haematoma: a systematic review and meta-analysis

Objective. Chronic subdural haematoma (CSDH) is becoming an increasingly important neurosurgical condition, especially given the aging world population and the increasing use of anticoagulant and antiplatelet medication. Clinicians regularly confront the dilemma of whether or not to restart anticoagulant and antiplatelet medication after CSDH, yet there is little evidence to support the decision-making process. This systematic review and meta-analysis aims to address this specifi c question. Methods. This systematic review and meta-analysis was conducted according to the PRISMA guidelines and has been registered with the PROSPERO international prospective register of systematic reviews (registration number CRD42012002509). Databases including MEDLINE, Cochrane, ISI Web of Knowledge, Embase and Google Scholar were searched for retrospective and prospective studies looking specifi cally at patients presenting with CSDH whilst on anticoagulant or antiplatelet medication which had data on subsequent recurrence and thromboembolic events. Results. Three relevant studies were found, totalling to 64 patients. In those restarted on anticoagulation, 11.1% experienced recurrences and 2.2% experienced thromboembolic events. In the control group that was not restarted on anticoagulation, 22.2% experienced recurrences and no patient experienced thromboembolic events. All recurrences and thromboembolic events occurred within the first 4 weeks of the initial surgical evacuation. Conclusions. The review seems to paradoxically suggest a lower bleeding risk and a higher thromboembolism risk when anticoagulation is restarted, although few concrete conclusions can be drawn from a pool of 64 patients. The decision on whether or not to restart anticoagulation in patients who present with CSDH whilst on anticoagulation has little empirical evidence to support a decision either way; more data are required to allow clinicians to make informed decisions about whether or not to restart anticoagulation, and if so, which drug, at what time-point and at what dose/therapeutic target.