Resident Physician University of New Mexico Health and Sciences Center Lafayette, LA, US
Introduction: Normal pressure hydrocephalus (NPH) predominately occurs in older patients and ventriculoperitoneal shunt (VPS) placement is the surgical treatment. CSF shunting procedures are subject to significant postoperative complication rates, which may negate the benefits of this treatment option for some patients. We investigated the use of frailty scoring for preoperative risk stratification for adverse event prediction in this population.
Methods: The National Inpatient Sample (NIS) was queried from 2018 to 2019 for patients aged ≥60 who had VPS performed for the primary diagnosis of NPH. The Risk Analysis Index (RAI) and modified 5-item Frailty Index (mFI-5) were calculated and RAI Crosstabulation was employed to trend frailty scores by the following binary outcome measures: overall complications, non-home discharge (NHD), extended length of stay (eLOS) (> 75th percentile), and mortality. Area under the receiver operating characteristic analysis (AUROC) was performed to assess the discriminatory accuracy of RAI and mFI-5 for primary outcomes.
Results: 5,257 NPH patients underwent VPS and there were 685 readmissions (7.4%), 596 perioperative complications (6.4%), and 94 (0.6%) mortalities. Increasing RAI score was significantly associated with increasing rates of postoperative complications: RAI 11-15 (5.4, n = 80), RAI 16-20 (5.7%, n = 291), RAI 21-25 (7.6%, n = 166), and RAI > 26 (11.6%, n = 56). The discriminatory accuracy of RAI was statistically superior (DeLong tests, p< 0.05) to mFI-5 for primary endpoints of mortality, NHD, and eLOS. All RAI C-statistics were > 0.60 with the strong discrimination for mortality within 30-days (c = 0.69, 95% CI: 0.68-0.70).
Conclusion : In a nationwide database analysis, increasing frailty, as measured by RAI, was a reliable predictor of non-home discharge, 30-day mortality, unplanned readmission, eLOS, and postoperative complications. The RAI also demonstrated superior discrimination in predicting adverse postoperative outcomes when compared to the mFI-5. This knowledge may help providers in preoperative counseling with patients.
