Mental Health Diagnoses and Surgical Outcomes: Inconsistent Conclusions,But Prehabilitation Holds Promise

Introduction

An estimated 26% of adults in the United States have a diagnosable mental illness in a given year. ¹ It is, therefore, likely a surgeon will operate on a patient with this potentially complicating influence.

Paredes et al. found ∼30% of Medicare beneficiaries undergoing various surgeries had an antecedent mental health (MH) diagnosis. ² The effects of a concomitant psychiatric condition included a higher rate of complications, readmissions, suicidal ideation in the first year postsurgery, and increased length of stay (LOS).

Although most patients in that study had a diagnosis of depression or anxiety, McBride et al. found that patients with a “serious” or ‘decompensated” MH condition experienced higher mortality rates, more time in intensive care unit (ICU), a greater number of postsurgical complications, and increased length of stay compared with patients without severe MH concerns.^3,4

A recent comprehensive review of MH on general surgery outcomes revealed impacts on postsurgical pain, LOS, complications, readmissions, wound healing, quality of care, and possibly mortality. ⁵

In line with optimizing surgical outcomes, the concepts of enhanced recovery after surgery (ERAS) and approaches such as prehabilitation or surgical optimization before surgery have gained great attention among surgeons.^6,7 Typical targets for prehabilitation are comorbid issues such as diabetes and smoking, but similar support has been suggested for MH issues. ⁸ However, the benefit of these efforts remains unclear with caution raised that more trials are needed to determine the best approaches for enhanced effectiveness.^9,10

This study was undertaken to further evaluate the impact of MH diagnoses on surgical outcomes and that of presurgical optimization on enhancing outcomes. At our institution, surgical patients with potentially complicating comorbid disorders can be referred to the surgical optimization clinic (SOC). Here the attempt is made to improve presurgical status by optimizing factors such as diabetic control, pulmonary function, and tobacco use. MH history and status are reviewed and support given, or where necessary, referral made for evaluation and treatment.

Materials and Methods

Clinical outcomes data for this retrospective review were abstracted from Crimson (Optum, Eden Prairie Minnesota), a severity adjusted database using the 3M APR DRG Grouper (3M, Maplewood Minnesota), a national standard for inpatient cases. The study sample consisted of SOC patients (N = 275) who had surgery between January 1, 2021, and December 31, 2022, both with (N = 28) and without (N = 247) an ICD-10 psychiatric diagnosis on admission.

The control group (N = 5170) consisted of patients who were not seen in the SOC, but had surgery during the same time frame both with (N = 307) and without (N = 4863) an ICD-10 psychiatric diagnosis. Three psychiatric diagnoses were surveyed: depression, anxiety, and post-traumatic stress disorder. All patients were 18 years of age or older. The research was approved by the system's institutional review board.

Quality metrics available in the data system used in this study included:

7-day readmission rate

We reported continuous variables as mean for the normal distribution and median for the abnormal distribution, and categorical variables as number (percent). Student's t-test or Wilcoxon rank sum test was used to analyze between group differences for the continuous variables. The chi-square test was used to analyze between-group differences for the categorical variables. The Fisher exact test was employed when any of the expected frequencies was five or less. All tests were two-sided with statistical significance set at a P value <.05. All the analyses were done by SAS 9.4 (SAS Institute, Cary NC).

Results

As given in Table 1, there was no significant difference in any outcome measure between all surgical (non-referred surgical optimization clinic) patients with a MH diagnosis and all surgical (non-referred surgical optimization clinic) patients without a MH diagnosis.

As given in Table 2, there was no significant difference in any outcome measure between SOC-referred patients with a MH diagnosis and surgical (non-SOC referred) patients with an MH diagnosis. However, with the exception of 7-day readmissions, those who were referred generally had better (though non-significantly so) outcomes, including LOS.

However, as given in Table 3, comparing SOC-referred patients (with or without a MH diagnosis) with non-referred patients (with or without a MH diagnosis), those who were referred (received optimization) had significantly better outcomes for 7-day readmissions, complication of conditions, and LOS.

Discussion

Although the surgical literature generally suggests that patients with pre-existing MH diagnoses do less well on various outcome measures, our study failed to confirm this. However, when comparing patients with an MH diagnosis who were or were not referred for presurgical optimization, those who were referred generally had better (though nonsignificantly so) outcomes, including LOS.

Furthermore, patients receiving preoperative optimization (regardless of MH status) demonstrated significantly improved outcomes compared with patients who did not receive presurgical optimization (regardless of MH status) with significantly fewer 7-day readmissions, complications of condition, and median LOS (shorter by 1 day).

Our study is limited by sample size and being drawn from a single institution. The possibility exists that with a larger sample, results may have more closely matched current literature. The percentage of patients in this study with a pre-existing MH diagnosis was also considerably less (10% for SOC-referred patients and 6% for non-SOC-referred patients) than that reported in other studies with ranges up to 50%.^11,12

Although it is unlikely that this study population is unique, differences might be attributed to intake procedures, SOC referral procedures, definitions, and/or data collection practices. In particular, it may be that the lack of difference in outcomes is due to the MH diagnoses studied being limited to three conditions: depression, anxiety, and post-traumatic stress disorder and not including other severe diagnoses such as schizophrenia.^3,4 The relative risk of different MH diagnoses for outcomes needs to be explored in greater depth.

Stain emphasized the importance of surgeons being aware of MH histories in their patients, but questioned how to best handle them. ¹³ He suggested it is neither feasible to delay surgery based on the presence of an MH diagnosis, nor is it reasonable to ask surgeons to manage these comorbid conditions.

However, his concerns are poignant as a 2021 review of surgical outcomes for patients with mental illnesses found that preoperatively patients were 7.5% to 40% less likely to be deemed surgical candidates, were less likely to receive testing, were more likely to present at later stages of their disease, or have delayed surgical care.

Postoperatively, patients with mental illness were more likely to require ICU admission, be up to three times more likely to have an increased LOS, have a 14% to 270% increased likelihood of postoperative complications, and have significantly higher health care costs. ¹⁴

Two ameliorative approaches seem viable. One is to refer patients preoperatively to an optimization program that addresses psychological as well as physiological parameters. The other (which can be used conjointly with prehabilitation efforts) is to request psychiatric consultation with these patients. However, as recently discussed, psychiatric consultation by surgeons may be underutilized. ¹⁵ Educating surgeons on the potential benefits of prehabilitation and consultation is needed to engage these methods to maximize outcomes and benefit both patients and surgeons.

Conclusion

Despite data differing from other research literature on the negative impact of MH diagnoses on surgical outcomes, this study lends support to existing data on the value of prehabilitation programs favorably affecting surgical outcomes overall. However, further study is needed to clarify conflicting results in patients with diagnosed mental illness at the time of surgery.