Anxiety’s Impact on Length of Stay Following Lumbar Spinal Surgery
Introduction: Despite some evidence that anxiety may affect length of stay (LOS), relatively little inquiry exists regarding this in neurosurgical literature.
It is well established that psychological factors affect spinal surgery outcomes.1,2 Surgical literature suggests that anxiety may affect length of stay (LOS).3,4 However, in a time of increasing number and cost of spinal procedures, relatively little inquiry exists regarding the influence of anxiety on LOS in neurosurgical literature. By way of inquiry we conducted the following retrospective study and our cohort was not subjected to any treatments or implementations. Institutional review board approval was not necessary.
At our institute, medical records of all patients (consecutively selected) who underwent elective lumbar decompression and fusion surgery from October 1, 2010, through September 30, 2013, were retrospectively reviewed. Exclusion criteria were staying for more than 20.4 days, 3 standard deviations (SDs) above the mean LOS (5.7 days, SD = 4.9), and a preoperative history of taking baclofen (chlorophenibut), used for advanced muscular disorders.
A total of 55 variables were collected from each patient (Table 1). Variables that were related to psychiatric problems included a history of anxiety, depression, and anxiolytic use. Anxiolytic medications were benzodiazepines, buspirone, and selective serotonin reuptake inhibitors (SSRIs). We divided our patients into 4 cohorts on the basis of their history of anxiety and anxiolytic use (Table 2).
LOS was measured from the first day of the procedure until time of discharge, measuring the days up to the first decimal place.
All collected variables (Table 1) were entered into a linear regression analysis (using SPSS software, version 19 [SPSS, IBM, Armonk, NY]), and the variables that showed an independent impact on LOS were identified and considered to be confounding variables (see Sidebar: Variables Identified Using Linear Regression and Multivariate Analysis Showing Significant Independent Impact on Hospital Length of Stay). To better isolate the impact of the 4 anxiety cohorts on LOS from the effect of the confounding variables, we used multivariate analysis.
After applying the exclusion criteria, the total number of patients considered in this study was 307 (see Table 3 for a detailed cohort description). The mean (standard deviation) LOS was 5.0 (2.9) days. For more details about the 4 anxiety cohorts see Table 2.
Of the 55 variables considered in the linear regression analysis, the variables that showed an impact on LOS, the confounding variables, were number of operated levels (p = 0.033), postoperative hemoglobin levels (p < 0.001), dural tear (p < 0.001), postoperative pulmonary embolism (p < 0.001), and postoperative urinary retention (p = 0.012).
Studying the LOS difference between the 4 anxiety cohorts using multivariate analysis and considering the confounding variables attained the following results: The LOS in cohort 1 was significantly longer than that of cohort 3 (mean difference, 1.9 days; p = 0.012) and cohort 4 (mean difference, 1.8 days; p = 0.003), with no differences between cohort 2 and the other cohorts.
Some of our study limitations were that the collection of variables, including comorbidity history, was taken from the patients' medical charts and not determined by diagnostic testing methods; also, LOS is always a weak outcome indicator because it can be affected by numerous and complicated factors.
Despite their both having histories of anxiety, cohort 1 stayed significantly longer than cohort 3. We believe cohort 3 possibly experienced situational as opposed to chronic anxiety, because they were not receiving any medications, making their psychological states similar to those of cohort 4. Cohort 2 did not significantly stay longer than any of the other groups. This is probably because their anxiolytic medications may have been taken for mental disorders other than anxiety.
Pursuant to the observed impact of psychological variables upon hospital LOS, several suggestions arose:
Better Preoperative Psychological Assessment
Several studies have proved successful in using the Minnesota Multiphasic Personality Inventories test preoperatively to categorize patients as having anxiety.5 These studies suggest that the lower the anxiety score, the more successful the patient's recovery. So, performing preoperative psychological tests would be of significant benefit.
On the basis of the patient's anxiety score, interventions could be implemented (ie, anxiolytic medications or education about the surgery) to help lower anxiety titers and thus decrease LOS. The cost of performing this test is approximately $25, according to our institute's psychologist; however, an extra day at the hospital costs approximately $2000.6
Better Preoperative Counseling
We further suggest providing preoperative education about the surgery that the patient is about to undergo to help ease anxiety. Despite preoperative education's ability to decrease anxiety before surgery, its effects on LOS are still unclear.7
Better Assessment of Preoperative Medications
Patients receiving psychotropic medications for long periods before the surgery may be getting extra pain medications. Their pain protocols need to be further investigated. If patients taking psychotropic medications are getting extra pain medications and this is affecting their ability to ambulate, this could be prolonging their LOS. Still, further prospective studies in this regard are warranted.
Our study suggests that those with a diagnosis of anxiety who are medicated for that condition have a longer LOS than those with no diagnosis of anxiety and who are not medicated for the condition. Further prospective perioperative studies appear warranted.
The author(s) have no conflicts of interest to disclose.
Mary Corrado, ELS, provided editorial assistance.
1. Menendez DE, Neuhaus V, Bot AG, Ring D, Cha TD. Psychiatric disorders and major spine surgery: epidemiology and perioperative outcomes. Spine (Phila Pa 1976) 2014 Jan 15;39(2):E111-22. DOI: http://dx.doi.org/10.1097/BRS.0000000000000064.