Association of Medical Comorbidities With Objective Functional Impairment in Lumbar Degenerative Disc Disease

Victor E Staartjes; Holger Joswig; Marco V Corniola; Karl Schaller; Oliver P Gautschi; Martin N Stienen

doi:10.1177/2192568220979120

Association of Medical Comorbidities With Objective Functional Impairment in Lumbar Degenerative Disc Disease

Global Spine J. 2022 Jul;12(6):1184-1191. doi: 10.1177/2192568220979120. Epub 2020 Dec 17.

Authors

Victor E Staartjes¹, Holger Joswig², Marco V Corniola³, Karl Schaller³, Oliver P Gautschi⁴, Martin N Stienen^{1

5}

Affiliations

¹ Department of Neurosurgery, Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Zurich, Switzerland.
² Department of Neurosurgery, Health and Medical University Potsdam, Ernst von Bergmann Hospital, Potsdam, Germany.
³ Department of Neurosurgery, Geneva University Hospital and Faculty of Medicine, Geneva, Switzerland.
⁴ Neuro- und Wirbelsäulenzentrum Zentralschweiz, Klinik St.Anna, Luzern, Switzerland.
⁵ Department of Neurosurgery, Kantonsspital St.Gallen, St.Gallen, Switzerland.

Abstract

Study design: Analysis of a prospective 2-center database.

Objectives: Medical comorbidities co-determine clinical outcome. Objective functional impairment (OFI) provides a supplementary dimension of patient assessment. We set out to study whether comorbidities are associated with the presence and degree of OFI in this patient population.

Methods: Patients with degenerative diseases of the spine preoperatively performed the timed-up-and-go (TUG) test and a battery of questionnaires. Comorbidities were quantified using the Charlson Comorbidity Index (CCI) and the American Society of Anesthesiology (ASA) grading. Crude and adjusted linear regression models were fitted.

Results: Of 375 included patients, 97 (25.9%) presented at least some degree of medical comorbidity according to the CCI, and 312 (83.2%) according to ASA grading. In the univariate analysis, the CCI was inconsistently associated with OFI. Only patients with low-grade CCI comorbidity displayed significantly higher TUG test times (p = 0.004). In the multivariable analysis, this effect persisted for patients with CCI = 1 (p = 0.030). Regarding ASA grade, patients with ASA = 3 exhibited significantly increased TUG test times (p = 0.003) and t-scores (p = 0.015). This effect disappeared after multivariable adjustment (p = 0.786 and p = 0.969). In addition, subjective functional impairment according to ODI, and EQ5D index was moderately associated with comorbidities according to ASA (all p < 0.05).

Conclusion: The degree of medical comorbidities appears only weakly and inconsistently associated with OFI in patients scheduled for degenerative lumbar spine surgery, especially after controlling for potential confounders. TUG testing may be valid even in patients with relatively severe comorbidities who are able to complete the test.

Keywords: comorbidity; degenerative disc disease; functional impairment; lumbar disc herniation; lumbar spinal stenosis; objective functional testing.