Binit J. Shah, MD December 8, 2011 Psychiatric and Psychological Consideration for SCS

Psych vs. Psych  Psychological  Trying to understand the patients current mental state  The ability to follow through on instructions  Realistic expectation of results, coping skills  Psychiatric  Capacity to give consent for the procedure  Substance abuse  Underlying Axis I or II pathology that needs to be treated before they can undergo a trial or would preclude them from trial/implant for the foreseeable future

History of Psych eval in SCS  C. Norman Shealy recognized the importance of psychological screening for SCS:  Absence of elevations on the MMPI (except depressive scale)  Emotional stability  Involvement in a rehabilitation program

Current state of psych eval  Centers for Medicare and Medicaid Services (CMS)  “Patients must undergo a careful screening, evaluation and diagnosis, by a multidisciplinary team prior to implantation. (Such screening must include psychological as well as physical evaluation)”

What is a psychological evaluation?  American Psychological Association  “Psychologists provide opinions of the psychological characteristics of individuals only after they have conducted an examination of the individual adequate to support their statement or conclusions.”  “When interpreting assessment results, including automated interpretations, psychologists take into account the purpose of the assessment and various factors, test- taking abilities, and other characteristics of the person being assessed such as situational, personal, linguistic, and cultural differences that might affect the psychologists' judgment or reduce the accuracy of their interpretation.”

Who should I refer to? SSomeone good SSomeone who is timely and responsive to you SSomeone who understands pain, the patient’s diagnosis SSomeone who understands what SCS really involves SSomeone who doesn’t approve all of your patients

Assessment begins in your office  You will (should) know the patient better than the person you are referring to  Give information that is relevant  Pt overly sedated in the office  Pt told by workman’s comp this is the next step of treatment  52 yo surgeon who wants to avoid all meds and stay functional  Give your impression of whether they are suitable

Don’t underestimate the reports of office staff  Patient calls multiple times a day to complain of pain  Patient repeatedly calls for refills early or after hours  Staff notice the patient walking vigorously in the hallway or outside the office  Other people are calling on behalf of the patient

What (should) happens during psych evaluation?  Review of medical records  Psychological testing/screening forms  Beck Depression Inventory, Hamilton Depression Rating Scale, Beck Anxiety Inventory, McGill Pain Questionnaire  Clinical interview  → This is really what the patient is being sent for  Assessment of risk factors/predictors of trial success

Psychological Tests  MMPI  Symptom Checklist 90-R  Derogatis Affects Balance Scale  Chronic Illness Problem Inventory  Spielberger State-Trait Anxiety Inventory (STAI) Scale and State- Trait Anger Scale  Absorption Scale  Locus of Control Scale  Sickness Impact Profile  Oswestry Disability Index  Roland Morris Questionnaire  Fear-Avoidance Beliefs Questionnaire

Clinical Interview

Risk Factors – patient beliefs  Pain is purely physical  Psychological/social factors aren’t important  Pain can only be relieved if the medical cause is eliminated  Medical technology holds the key to treatment

Risk Factors – physician beliefs  Failure of intervention is the patient’s fault  Trial outcome is the only predictor of success  Because a procedure is reversible or non- destructive, patient selection can be less stringent  Relief of pain will automatically lead to improvements in all other areas (psychological well being, increased function)

Price D, Finniss DG, Benedetti F: A comprehensive review of the placebo effect: recent advances and current thought, Annu Rev Psychol 59: , Expectation  Can contribute significantly to patient outcome  Overall, placebo effect is 2 on NRS of 0-10  When patients are given the expectation of benefit, the can have as much as a 5-point reduction in pain.

Clinical Summary  At this time, there are no contra-indications to the use of spinal cord stimulation in this patient. There is no evidence of severe untreated Axis I disorder, no evidence of somatoform disorder, no severe Axis II pathology that needs to first be addressed. Patient has a logical thought process free of psychotic influences and is able to understand the risks, benefits and alternatives of the procedure as well as what is expected from a patient perspective. Has a realistic goal regarding pain improvement, and understands limitations such as subsequent MRI and is able to verbalize understanding of wound care instructions during the trial and post-op period.

Be specific in your request  Psychological/psychiatric evaluation for appropriateness for SCS trial/implant  Evaluate for severe or untreated Axis I diagnoses and somatoform disorders  Evaluate for Axis II diagnoses  Evaluate capacity to give consent for the procedure

North R, Shipley J: Practice parameters for the use of spinal cord stimulation in the treatment of chronic neuropathic pain, Pain Med 8(suppl 4): S200-S275, What is the value of psych eval?  “We lack sufficient information to predict SCS outcome from the result of a pretreatment psychological evaluation, but SCS, as is the case for every interventional pain treatment, is reserved for patients with no evident unresolved major psychiatric co-morbidity.”  “…provides patient selection information by identifying the small percentage of patients who might benefit from psychological treatment before undergoing SCS therapy or in whom SCS therapy might be complicated by psychological factors.”

Long DM et al: Electrical stimulation of the spinal cord and peripheral nerves for pain control: a 10-year experience, Appl Neurophysiol 44(4):207–217, What is the value of psych eval?  70% success rate in those who had a psych eval vs. 33% in those who did not