Which are safer—anticoagulants or antiplatelet agents—in elderly patients with subdural hematoma who are restarted on those medications after surgery?

In this systematic review of elderly patients using anticoagulants or antiplatelet medications at the time of a treated traumatic subdural hematoma (SDH), subsequent hematomas were not associated with resuming antiplatelet medications. However, resuming anticoagulant medication was associated with an increased rebleeding risk. These conclusions, however, must be tempered by conflicting results from low-quality to moderate-quality studies. (LOE = 2a)

Nathan S, Goodarzi Z, Jette N, Gallagher C, Holroyd-Leduc J. Anticoagulant and antiplatelet use in seniors with chronic subdural hematoma: Systematic review. Neurology 2017;88(20):1889-1893.  [PMID:28411235]

Systematic review

Self-funded or unfunded

Various (meta-analysis)

These authors searched multiple databases and registries to identify studies that evaluated adults older than 65 years with traumatic SDHs (acute or chronic) who were taking anticoagulants or antiplatelet agents and who resumed taking those medications after surgical intervention. Two authors independently assessed which papers to include and assessed the risk of bias for the included studies. The authors included 7 studies with 2275 patients. Only one study was thought to be of low risk of bias. The bulk of patients had burr holes with closed drainage. Overall, the studies were methodologically dissimilar, making pooling of the data unwise. Four of the studies provided combined data on resuming anticoagulants or antiplatelet agents. None of the studies found that antiplatelet use was significantly associated with subsequent SDH. Although 2 studies found nearly a twofold increased risk associated with the resumption of anticoagulants and SDH, only one was statistically significant. The timing of resuming the medications was highly variable and no patterns can be ascertained to determine what timing is safest. These kinds of studies cannot address the influence of channeling bias: when clinicians choose to treat some patients differentially based on the perception that one intervention might be safer or more effective than another in a specific patient. For example, frail patients may be less likely to have been giving anticoagulants and less likely to have surgery, and these unmeasured factors potentially influence the study outcomes.