Frailty and Outcomes after Craniotomy or Craniectomy for Atraumatic Chronic Subdural Hematoma

Frailty is a measure of decreased physiologic reserve and has been associated with increased morbidity and mortality in a variety of surgical disciplines. No data exist regarding the relationship of frailty with adverse outcomes in craniotomy for chronic subdural evacuation. We assessed the relationship between frailty and the incidence of major postoperative complication, discharge destination other than home, 30-day readmission, and 30-day mortality after craniotomy for atraumatic subdural evacuation.

A retrospective cohort study was conducted on a population of 1647 adult patients undergoing craniotomy for evacuation of atraumatic subdural hematoma in the 2005-2018 American College of Surgeons National Surgical Quality Improvement Program database. Frailty was assessed using the modified frailty index (mFI-5). Multivariable logistic regression was performed using all covariates deemed eligible through clinical relevance and statistical significance.

The overall rates of major complication (25.4%), discharge to destination other than home (49.8%), 30-day readmission (11.7%), and 30-day mortality (12.8%) in this analysis were high and rose with increasing frailty. In multivariable regression analyses, medium frailty (mFI-5 = 2) was associated with increased odds of major complication (adjusted odds ratio [aOR] 1.64, 95% confidence interval [CI] 1.03-2.63), discharge to destination other than home (aOR 2.04, 95% CI 1.38-3.02), and 30-day mortality (aOR 2.27, 95% CI 1.08-4.78). High frailty (mFI-5 >2) was associated with increased odds of 30-day mortality (aOR 2.85, 95% CI 1.13-7.14).

Preoperative frailty, as determined by mFI-5, is associated with increased odds of major postoperative complication, discharge to destination other than home, and 30-day mortality after craniotomy for chronic subdural hematoma.