Leveraging HFRS to assess how frailty affects healthcare resource utilization after elective ACDF for CSM

Frailty is a common comorbidity associated with worsening outcomes in various medical and surgical fields. The Hospital Frailty Risk Score (HFRS) is a recently developed tool which assesses frailty using 109 International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) comorbidity codes to assess severity of frailty. However, there is a paucity of studies utilizing the HFRS with patients undergoing anterior cervical discectomy and fusion (ACDF) for cervical spondylotic myelopathy (CSM).

The aim of this study was to investigate the impact of HFRS on health care resource utilization following ACDF for CSM.

A retrospective cohort study was performed using the Nationwide Inpatient Sample (NIS) database from 2016-2019.

All adult (≥18 years old) patients undergoing primary, ACDF for CSM were identified using the ICD-10 CM codes.

Weighted patient demographics, comorbidities, perioperative complications, LOS, discharge disposition, and total admission costs were assessed.

The 109 ICD-10 codes with pre-assigned values from 0.1 to 7.1 pertaining to frailty were queried in each patient, with a cumulative HFRS ≥5 indicating a frail patient. Patients were then categorized as either Low HFRS (HFRS<5) or Moderate to High HFRS (HFRS≥5). A multivariate stepwise logistic regression was used to determine the odds ratio for risk-adjusted extended LOS, non-routine discharge disposition, and increased hospital cost.

A total of 29,305 patients were identified, of which 3,135 (10.7%) had a Moderate to High HFRS. Patients with a Moderate to High HFRS had higher rates of 1 or more postoperative complications (Low HFRS: 9.5% vs. Moderate-High HFRS: 38.6%, p≤.001), significantly longer hospital stays (Low HFRS: 1.8±1.7 days vs. Moderate-High HFRS: 4.4 ± 6.0, p≤.001), higher rates of non-routine discharge (Low HFRS: 5.8% vs. Moderate-High HFRS: 28.2%, p≤.001), and increased total cost of admission (Low HFRS: $19,691±9,740 vs. Moderate-High HFRS: $26,935±22,824, p≤.001) than patients in the Low HFRS cohort. On multivariate analysis, Moderate to High HFRS was found to be a significant independent predictor for extended LOS [OR: 3.19, 95% CI: (2.60, 3.91), p≤.001] and non-routine discharge disposition [OR: 3.88, 95% CI: (3.05, 4.95), p≤.001] but not increased cost [OR: 1.10, 95% CI: (0.87, 1.40), p=.418].

Our study suggests that patients with a higher HFRS have increased total hospital costs, a longer LOS, higher complication rates, and more frequent nonroutine discharge compared with patients with a low HFRS following elective ACDF for CSM. Although frail patients should not be precluded from surgical management of cervical spine pathology, these findings highlight the need for peri-operative protocols to medically optimize patients to improve health care quality and decrease costs.