The Effect of Frailty and Patient Comorbidities on Outcomes After Acute Subdural Hemorrhage: A Preliminary Analysis

Frailty is associated with worse outcomes across a variety of neurosurgical diseases. However, its effect on acute subdural hemorrhage (aSDH) outcomes is unclear. The goal of this study is to compare 3 measures of frailty with the gold standard (i.e., initial Glasgow Coma Scale [iGCS] score) for predicting outcomes after aSDH. Patients who presented between January 2016 and June 2018 were retrospectively identified based on International Classification of Diseases codes for aSDH. Patients' modified Frailty Index (mFI), temporalis muscle thickness (TMT), and age-adjusted Charlson Comorbidity Index (CCI) were calculated. Primary end points were death and discharge home. Of 167 patients included, the mean age was 63.4 ± 1.9 years, the average CCI was 3.4 ± 0.2, mFI was 1.4 ± 0.1, TMT was 7.1 ± 0.2 mm, and iGCS score was 11.9 ± 0.3. Sixty-nine patients (41.3%) were discharged home and 32 (19.2%) died during hospitalization. In multivariate analysis, decreasing iGCS score (odds ratio [OR], 0.84; 95% confidence interval [CI], 0.74–0.96; P = 0.0112) and midline shift (OR, 1.27; 95% CI, 1.08–1.50; P = 0.0048), but not age or frailty, predicted mortality. In addition to iGCS score (OR, 1.26; 95% CI, 1.10–1.44; P = 0.0011), lower CCI (OR, 0.32; 95% CI, 0.14–0.74; P = 0.0071) and larger TMT (OR, 2.63; 95% CI, 1.16–5.99; P = 0.0210) independently predicted increased rates of discharge home. mFI was not independently associated with either primary end point in multivariate analysis. iGCS score predicts both mortality and discharge location after aSDH better than do age or frailty. However, CCI and TMT, but not mFI, are useful prognostic indicators of discharge to home after aSDH. The iGCS score should continue to be the primary prediction tool for patients with aSDH; however, frailty may be useful for resource allocation, especially when nearing discharge.