Does insurance status play a role in predicting outcomes after surgery?

Jonathan Rasouli
Jonathan Rasouli

Following on from studies examining the socioeconomic and racial factors influencing the outcomes from spinal surgery, Jonathan Rasouli (Cleveland Clinic, Cleveland, USA) and colleagues have sought to stratify the outcomes from anterior cervical fusion surgery (ACDF) surgery based upon patients’ insurance status. The study team found that patients with Medicare or Medicaid fared worse to those with commercial insurance. Here, for Spinal News International, he discusses the research and its implications.

Innovation in the quality and delivery of care for spine patients has been a formidable task. Spine care costs are rapidly rising, procedural reimbursements are declining, and there is more scrutiny than ever on public reporting of surgeon-specific outcomes and complications.1 With these factors in mind, there has been a system-wide initiative to make the spine service line safer, cheaper, and more efficient.

One rapidly evolving aspect of spine care is the risk stratification of patients prior to surgery based on modifiable and non-modifiable factors. There are innumerable studies published that examined virtually every possible medical and surgical risk factor known to man after any spinal surgery. However, there has been a small, but steadily growing body of literature examining racial and socioeconomic factors that may play a large role in predicting outcomes. At first glance, it seems strange and almost unfathomable that in today’s healthcare environment that these discrepancies still exist. As we have seen in recent publications by Feng et al and Elsamadicy et al, race and socioeconomic differences play major roles in predicting risk of surgical complications, postoperative outcomes, and patient satisfaction after surgery.2,3 With these factors in mind, our spine research team at the Icahn School of Medicine at Mount Sinai wondered if insurance status could also play a role in predicting outcomes after surgery. As part of an effort to improve the quality and delivery of comprehensive spine care to our patients, we decided to launch a multidisciplinary project to thoroughly and objectively examine outcomes at our institution.

In our most recent publication, we decided to start with the anterior cervical discectomy and fusion (ACDF), as it was one of the most common surgical procedures performed at our hospital.4 We designed a retrospective study examining records and administrative data for all patients who underwent an ACDF at the Mount Sinai Hospital between January 1, 2008 and November 30, 2016. Patients were assigned to one of five insurance categories: uninsured (including self-pay), managed care organization, commercial indemnity insurance (including automobile insurance, Blue Cross/Blue Shield, Aetna, Cigna, United, no-fault insurance, and workers’ compensation), Medicare, and Medicaid. We looked at standard demographic variables and measures of outcome such as comorbidity burden, time to extubation, length of stay, readmission rates, and emergency department visits.

Our results were quite surprising, but not unexpected. After adjusting for age, co-morbidities, and number of operated levels, we found that Medicare patients had higher rates of prolonged length of stay than patients with commercial insurance (OR: 2.44, 95% CI: 1.13–5.27%, p = 0.004). Medicaid patients had higher rates of 30- and 90-day emergency department visits than patients with commercial insurance (OR: 4.12; 95% CI: 1.43-11.93; p = 0.0009; OR: 3.28; 95% CI: 1.34-8.03; p = 0.0009). Managed care patients had higher rates of 30-day readmission compared to commercial insurance as well (OR: 3.41; 95% CI: 1.00-11.57; p = 0.0123). Simply stated, when all factors were kept equal, Medicare and Medicaid patients had higher rates of prolonged LOS and postoperative ED visits, respectively, compared to commercial patients after ACDF. Further prospective studies will have to be performed in order to elucidate the reasons behind these discrepancies, but there were consistent systems-based issues that kept popping up during our data analysis that are worth mentioning as areas of potential improvement.

First, we found differences in the outcomes between Medicare and Medicaid patients which suggests that they should be analysed as separate cohorts, rather than being grouped together as has been performed in prior studies. Second, one of the reasons why patients with Medicare insurance may have had a prolonged length of stay is due to difficulties with postoperative placement to an acute rehabilitation facility or skilled nursing home secondary to insurance coverage. These patients may have an artificially extended length of stay secondary to administrative and placement reasons rather than anything inherent to the surgery. Third, Medicaid patients had significantly higher 30- and 90-day emergency department visits, which could be due to lack of access to care and the perceived value of emergency department care itself.

It is sobering food for thought when the results of our study suggest that simply being a beneficiary of Centers for Medicare and Medicaid Services (CMS) can potentially increase your risk of adverse outcome after an elective ACDF. Again, while the reasons for these findings need to be further investigated, the system-based implications are important. For tertiary care centres which treat a large population of CMS beneficiaries, there may be an inherent bias towards worse outcomes compared to a hospital that primarily treats patients with commercial insurance. The public reporting of surgical outcomes, patient satisfaction scores, and complications is becoming increasingly prevalent and these findings may negatively skew results for academic teaching hospitals. While there have been advances on a larger scale when addressing these potential discrepancies in healthcare delivery, we found this holds true even after ACDF. It seems intuitive that patients who are older or poorer, as a whole, will do poorer on most health-related quality metrics because they have less access to medical resources. However, our study demonstrated that discrepancies hold true even when these variables are adjusted. This suggests that simply being on an insurance plan from CMS is a predictor of worse outcome after ACDF.

Indeed, there were limitations to our study, namely, the data used came from a single academic medical centre located in a large urban setting. The patient population was skewed towards more commercial and managed care plans rather than CMS, suggesting these results may not be generalisable to hospitals that primarily treat CMS patients. This also hindered the analysis from adequately evaluating the impact of being uninsured on in-hospital and post-discharge outcomes, as <1% of the study population lacked insurance. A more homogenous cohort of all patients with cervical spinal pathologies, stratified by procedure, could be utilised to allow for greater understanding of the differences in complication rates, both within and between procedural groupings. Lastly, the retrospective nature of this study also limits the generalisability of the results and we believe further, prospective studies are warranted.

In conclusion, the results of this study provide us further data and insight into our ability to accurately predict outcomes after spinal surgery. It is becoming increasingly apparent that there are many more intrinsic and extrinsic factors that influence patient outcome, rather than the inherent characteristics of the surgery alone. CMS beneficiaries appear to have an increased risk of adverse events after elective ACDF surgery, even when all factors are kept equal. Ultimately, our collective awareness of these complex issues and our ability to adapt and pre-emptively intervene will allow us to advocate for our patients in clearer and more meaningful ways.

Jonathan J Rasouli, is a neurosurgeon at the Cleveland Clinic (Cleveland, USA).


  1. Parker SL, Chotai S, Devin CJ, et al. Bending the Cost Curve-Establishing Value in Spine Surgery. Neurosurgery. 2017;80(3S):S61-S69.
  1. Feng R, Finkelstein M, Bilal K, Oermann EK, Palese M, Caridi J. Trends and Disparities in Cervical Spine Fusion Procedures Utilization in the New York State. Spine (Phila Pa 1976). 2018 May 15;43(10):E601-E606.
  1. Elsamadicy A, Adogwa O, Reiser E, Fatemi P, Cheng J, Bagley C. The Effect of Patient Race on Extent of Functional Improvement After Cervical Spine Surgery. Spine. 2016;41(9):822-826.
  1. Rasouli JJ, Neifert SN, Gal JS, et al. Disparities in Outcomes by Insurance Payer Groups for Patients Undergoing Anterior Cervical Discectomy and Fusion. Spine (Phila Pa 1976). 2019 Dec 10. doi: 10.1097/BRS.0000000000003365. [Epub ahead of print]


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