Neuropsychological Assessment of Pain Patients

Greg J. Lamberty et al. Neuropsychological Assessment of Patients

8 NEUROPSYCHOLOGICAL ASSESSMENT OF PAIN PATIENTS

Greg J. Lamberty, Carly R. Anderson, and Laura E. Krause

Introduction Chronic pain, and many of the clinical disorders associated with it, is a vexing clinical challenge. The influence of pain on cognitive functioning and how to best characterize pain with psychometric measures has become a more common referral question in neuropsychology practice. This is likely due to persistent efforts to identify the underlying causes of disorders like fibromyalgia and complex regional pain syndrome (CRPS). A simple biological explanation of these conditions would presumably allow a straightforward therapeutic approach, but the clinical reality is that chronic pain is usually associated with many complex and interacting factors, particularly where the issue of disability is concerned. Therefore, neuropsychologists are often asked to assist in evaluating patients with pain disorders, regardless of the presumed etiology. Today’s psychology practice environment is increasingly characterized by a bifurcation into clinical intervention and assessment practices. While this is difficult to quantify with practice surveys or other literature, personal experience and anecdotal accounts indicate that neuropsychologists are frequently called upon to perform assessments that are not strictly neuropsychological in nature. Because neuropsychologists conduct assessments, they receive referrals to assess the psychological readiness of individuals to go through complex medical procedures (e.g., bariatric surgery, implantation of medical devices), to determine fit- ness for duty in high-stress occupations, or to assess the psychological/emotional adjustment of individuals with chronic pain, as examples. Health psychologists have typically done these kinds of evaluations, but many neuropsychologists have branched out into these assessment areas. Neuropsychologists are trained to assess personality, emotional, and behavioral functioning, as these are so frequently impacted in neurologic disease and Neuropsychological Assessment of Patients 231 neuropsychiatric disorders. Part of the evolution of the practice patterns noted earlier involves the common finding that individuals without significant neurologic underpinnings to their clinical presentation nonetheless complain of cognitive difficulties. The regularity of somatoform symptoms in neuropsychological referrals has become more of a focus in neuropsychology practice in recent times (Binder & Campbell, 2004; Lamberty, 2008) and this has likely led to neuropsychologists seeing more individuals with pain disorders (Greiffenstein & Bianchini, 2013). The extent to which most neuropsychologists have received specific training in evaluating patients with chronic pain is unclear. While personality assessment is a routine part of the neuropsychological exam, this is usually done in the context of known or suspected neurologic or neuropsychiatric disorders and not necessarily as a means to facilitate treatment of specific clinical presentations. This distinction is critical in determining the nature of the evaluation to be conducted.

Role Clarification in Assessment of Patients With Pain Disorders

Neuropsychological Versus Psychological Assessments Even in well-established practices and hospital-based neuropsychology services there can be confusion about the nature of services provided by neuropsychologists. Ideally, referral sources are familiar with what neuropsychologists can deliver in terms of assessment services, but this is often an evolving process. It is beyond the scope of this chapter to discuss practice models, though it is important for neuropsychologists to be clear about their assessment services and the kind of specialty services they might offer. Attaining competence in assessing complex patient presentations is obviously essential and this will often involve extra read- ing, workshops, and consultation with colleagues. Neuropsychologists are strongly encouraged to clarify their role with referral sources. For the purposes of this chapter, we assume that most neuropsychologists are asked to evaluate patients with pain disorders to rule out neurologic underpinnings of reported cognitive difficulties. However, in the broader psychological context it is likely assumed that a more comprehensive psychological evaluation will also be conducted. Typical neuropsychological evaluations serve a descriptive or diagnostic purpose more so than a treatment planning purpose. While diagnosis and treatment planning should coincide, a range of more specific measures have emerged from the pain literature that seek to identify qualities of the pain experience and patients’ responses to intervention as a means of evaluating treatment efficacy.

Forensic Versus Clinical Assessments Distinctions between clinical and forensic practice in neuropsychology have been recognized for many years (Larrabee, 2011; Sweet, 1999). In forensic evaluations, neuropsychologists are typically asked to opine on the presence, nature, and severity 232 Greg J. Lamberty et al. of cognitive deficits, as well as significant personality, emotional, and behavioral dysfunction. The neuropsychologist’s role as an expert is to assist the trier of fact in making a determination about whether a claimant was injured or suffered dam- ages, and the extent to which other factors are involved. Broadly speaking, forensic evaluations are less likely to request specific information about treatment or intervention. As such, the neuropsychologist’s role is more purely evaluative. A clinical evaluation is more likely to include both a characterization of the patient’s functioning and recommendations for intervention. In this instance, the neuropsychologist will benefit from employing measures that are more descriptive and more associated with treatment outcome studies. The purpose of the evaluation will also determine what kinds of measures will be employed in the assessment process. If the neuropsychologist has a regular relationship with treating clinicians, it is more likely that specific questions about response to interven- tions will be a focus of the evaluation.

Epidemiology of Pain Disorders Prevalence estimates for pain disorders vary widely, mostly as a function of presumed etiology (e.g., chronic pain, fibromyalgia, CRPS). For the purposes of this chapter we will focus on the chronic pain literature, as this broad descrip- tor is the most prevalent and widely investigated in the realm of pain disorders. Further, many conditions involving pain are viewed as indistinct and subsumed under the umbrella of chronic pain. The reader is directed to the following studies and websites for prevalence statistics related to fibromyalgia (Bennett et al., 2007; Haviland, Banta, & Przekop, 2011; www.cdc.gov; http://fmaware.org) and CRPS (Bruehl & Chung, 2007; De Mos et al., 2007; www.ninds.nih.gov; Sandroni et al., 2003). A recent internet-based survey in a nationally representative sample of more than 27,000 adults in the United States demonstrated the prevalence of chronic pain to be 30.7% ( Johannes et al., 2010). This estimate is higher than that noted in a European sample, which demonstrated a 20% rate of chronic pain in adults (van Hecke, Torrance, & Smith, 2013). Despite differences in prevalence, current literature indicates similar cross-cultural patterns, societal concerns, and contribu- tory factors related to chronic pain. A major concern is that the vast majority of individuals suffering from chronic pain are managed in primary care rather than specialty pain clinics (see van Hecke, Torrance, & Smith, 2013). It is thought that a lack of specialized knowledge among primary care providers leads to a greater reliance on prescription narcotics as a primary means of pain management. Chronic pain is associated with significant financial burden worldwide. Recent US estimates of health care costs associated with chronic pain ranged from $560 to $635 billion annually; these estimates are higher than the annual costs of heart disease ($309 billion), cancer ($243 billion), and diabetes ($188 billion) (Gaskin & Richard, 2012). European studies report a similar financial impact, with estimates Neuropsychological Assessment of Patients 233

TABLE 8.1 Modifiable and Non-modifiable Influences on Chronic Pain

Modifiable Non-modifiable Pain Age Mental Health Sex Other Comorbid Conditions Cultural/Ethnic Background Smoking Socioeconomic Background Alcohol History of Trauma or Interpersonal Violence Obesity Heredity—Genetics and Environment Physical Exercise Nutrition Sleep Occupational Factors

Adapted from van Hecke, Torrance, & Smith, (2013). of €200 billion annually (Institute of Medicine, 2011). These estimates are likely conservative as the presence of chronic pain complicates the symptoms, treatment, and prognosis of many other health conditions. Consequently, individuals with chronic pain and comorbid mental or physical health conditions are likely to be high service utilizers who often fail to benefit from narrow, pharmacologically based approaches to pain management. Recent epidemiological reviews identify numerous biological, psychological, and social factors that contribute to the development, maintenance, and outcome of chronic pain. These factors, categorized as modifiable versus non-modifiable (van Hecke, Torrance, & Smith, 2013), are summarized in Table 8.1.

Non-modifiable Influences on Chronic Pain The prevalence of chronic pain is consistently higher in females (34.3%) than in males (26.7%) ( Johannes et al., 2010). Research examining the roles of sex (biological) and gender (role) has demonstrated that women have lower pain thresh- olds and tolerance, experience pain more intensely, and show different analgesic sensitivity (Craft, Mogil, & Aloisi, 2004; Greenspan et al., 2007; Unruh, 1996; Wiesenfeld-Hallin, 2005). However, women also tend to seek pain treatment at a higher rate than men, which may contribute to perceived gender disparity. Different ethnic backgrounds are associated with greater risk for chronic pain; however, prevalence is generally consistent between developed (37%) and developing (41%) countries (Tsang et al., 2008), suggesting more specific ethno- cultural differences in pain perception, sensitivity, and quality of treatment (see van Hecke, Blaire, & Smith, 2013). An inverse relationship between chronic pain prevalence and socioeconomic status is also well established (Blyth, 2008; Pole- shuck & Green, 2008) and likely relates to multiple factors such as living circum- stances, education, and access to care. 234 Greg J. Lamberty et al.

Genetic factors are often invoked to explain many of the non-modifiable risk factors for chronic pain. Despite impressive advances in genetic research, it has been difficult to parse the role of genes from broad environmental sources of variation (van Hecke, Torrance, & Smith, 2013). Aside from genetics, biological underpinnings of chronic pain may include hormonal contributions, peripheral effects of sex hormones, endogenous opioid systems, and N-methyl-D-aspartate (NMDA) receptor function. For complete review of the biological factors, see a recently published critical review of the literature by Fillingim et al. (2009).

Modifiable Influences on Chronic Pain Modifiable risk factors for chronic pain do not occur in isolation. In a variety of clinical settings, a complex presentation that involves comorbid physical and mental health conditions and suboptimal health behaviors tends to be the rule rather than the exception. Consequently, similar to distinguishing between nature and nurture, specifying the variance contributed by each of these factors is a formida- ble task for researchers. In general, research demonstrates that each of these factors contributes to greater risk and poorer outcome for chronic pain (for review, see Smith, Macfarlane, & Torrance, 2007; van Hecke, Torrance, & Smith, 2013). Further, the specific relationship between mental health and chronic pain is bidi- rectional in etiology (Von Korff et al., 1993). Over time, a downward spiral can occur and conditions such as depression and anxiety can become indistinguish- able from, or augment the experience of, chronic pain (van Hecke, Torrance, & Smith, 2013). Similarly, sleep disturbance may precede onset of chronic pain or be a consequence of the condition; it may also relate to other modifiable factors (e.g., depression, obesity) and contribute to poor prognosis.

Psychological Assessment of Chronic Pain The complexity of relationships between physical, social, emotional, cognitive, and cultural aspects in chronic pain conditions such as fibromyalgia and CRPS can lead to difficult evaluative and diagnostic decisions. A recent systematic review of functional outcome measures for patients with CRPS concluded that there is a lack of reliable, valid, and consistently used measures across settings (Packham et al., 2012). Further, the difficulties inherent in attempting to quantify the subjective experience of pain is well documented and poses additional challenges, as the self-report of pain can itself be considered a pain behavior that often does not correlate with objective measures of functioning (Harden et al., 2013; Williams & Schilling, 2009). Barr (2013) provides a review of the history underlying psychological con- ceptualizations of pain as well as self-report measures that are commonly utilized to assess variables related to the pain experience, some of which are listed in Table 8.2. The inclusion of these measures was also informed by recommendations from the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) workgroup (Dworkin et al., 2005). Recommended Neuropsychological Assessment of Patients 235

TABLE 8.2 Psychological Assessment Measures for Patients With Pain Disorders

Pain Intensity Emotional Functioning Pain Numeric Rating Scale (NRS) Beck Depression Inventory—II (BDI-II) Pain Catastrophizing Scale (PCS) Health Survey, Short Form (SF-36) Visual Analog Scale (VAS) Profile of Mood States (POMS)

Functional/Pain Anxiety Measures Multidimensional Assessment Scales Pain Anxiety Symptoms Scale (PASS) Brief Pain Inventory (BPI) Tampa Scale of Kinesiophobia (TSK) McGill Questionnaire (MPQ) Fear Avoidance Belief Questionnaire (FABQ) Multidimensional Pain Inventory (MPI)

Personality Measures Minnesota Multiphasic Personality Inventory-2 (MMPI-2/MMPI-2-RF) Personality Assessment Inventory (PAI) NEO Personality Inventory (NEO-PI-3) measures may help to elucidate pain-specific variables while also exploring functional targets for behavior change and treatment recommendations (Harden et al., 2013; Williams & Schilling, 2009). In clinical settings, all such measures should be used in conjunction with a thorough clinical interview that includes psychiatric and substance use history, psychosocial stressors, expectations for pain management and overall well-being. In the context of a neuropsychological assessment, the inclusion of pain related measures needs to be weighed against the overall evaluation goals and time constraints. Several commonly utilized measures are described in the following paragraphs. The Multidimensional Pain Inventory (MPI; Kerns, Turk, & Rudy, 1985) con- sists of 52 items assessing pain intensity/subjective experiences, perceived impact of pain on support members, and interference of pain on activities of daily living. The MPI was designed from a cognitive-behavioral theoretical orientation and provides information relevant to a biopsychosocial conceptualization of chronic pain. Empirically derived subgroups have been developed from responses to the MPI to identify three coping styles: Adaptive Coping (AC), Interperson- ally Distressed (ID), and Dysfunctional (DYS) (Turk & Rudy, 1988). In a sample of patients with work-related musculoskeletal chronic pain disorders, those endorsing dysfunctional coping styles reported greater psychosocial distress and were found to terminate earlier from multidisciplinary chronic pain rehabilitation programs (Choi, Mayer, Williams, & Gatchel, 2013). Given that treatment recommendations for chronic pain conditions, including both fibromyalgia and CRPS, often include a combination of coping skills training along with medication, exercise, and functional rehabilitation (Carville et al., 2008; Goldenberg, Burckhardt, & Crofford, 2004; Harden et al., 2013), these empirically derived MPI coping styles may provide useful information to guide treatment recommendations for referring providers. 236 Greg J. Lamberty et al.

The Pain Catastrophizing Scale (PCS; Sullivan, Bishop, & Pivik, 1995) is a 13-item scale with three subscales: rumination, magnification, and helplessness. The PCS is utilized to tap into maladaptive thought patterns that negatively impact and exacerbate the pain presentation. For example, rumination about general physical health complaints has been found to result in magnification of perceived symptoms, and pain catastrophizing has been linked with poorer response to medical treatment (Block, Gatchel, Deardorff, & Guyer, 2003; Sansone & San- sone, 2012). In addition, higher levels of pretreatment rumination have been correlated with higher pain intensity ratings, higher opioid use, activity avoidance, suicidal ideation, and longer hospital stays (Keefe et al., 2004; Sullivan, Bishop, & Pivik, 1995). Cognitive responses such as catastrophizing have been found to mediate the effects of neuroticism on pain anxiety, leading to increased anxiety, anger, and emotional distress along with fear of movement in patients with chronic pain (Martinez, Sanchez, Miro, Medina, & Lami, 2011). Several measures have been developed to assess fear and avoidance in patients with chronic pain, including the Tampa Scale of Kinesiophobia (TSK; Vlaeyen, Kole-Snijders, Boeren, & Van Eek, 1995), the Fear Avoidance Belief Question- naire (FABQ; Waddell, Newton, Henderson, Somerville, & Main, 1993), and the Pain Anxiety Symptoms Scale (PASS; McCracken, Zayfert, & Gross, 1992). Pain- related fear has been associated with reduced effort on cognitive tasks, as well as decreased physical activity and prediction of long-term disability status (Vlaeyen & Linton, 2000). Further, in a sample of patients with chronic back pain, fear related to movement and possible reinjury was found to be more predictive of treatment outcome than was pain intensity (Crombez, Vlayen, Heuts, & Lysens, 1999). Pain- related fear of movement is often associated with activities related to the original injury as well as potential activities that could cause reinjury, leading to further decreases in physical and emotional functioning (De Peuter, de Jong, Crombez, & Vlaeyen, 2009; Vlaeyen et al., 1995). Consistent with this conceptualization, De Peuter and colleagues (2009) reviewed treatments for pain-related fear in chronic musculoskeletal pain, and found that exposure therapy (i.e., graduated activity) had the best long-term effects on reduction of severe disability. The relationship between various chronic pain diagnoses and corresponding personality measures continues to receive attention, as does the importance of identifying measures to adequately assess state-trait aspects of the cognitive, emotional, and social comor- bidities that have been associated with chronic pain (Torres et al., 2013). Broader measures of personality and psychopathology have been used to evaluate pain-related concerns. The Personality Assessment Inventory (PAI; Morey, 1991) has been found to be useful in identifying psychological and personality constructs within patients with chronic pain (Karlin et al., 2005), to identify malingered pain-related disability (Hopwood, Orlando, & Clark, 2010) and to predict early termination from comprehensive pain rehabilitation programs (Hop- wood, Creech, Clark, Meager, & Morey, 2008). Findings from the NEO Personal- ity Inventory (NEO-PI-R; Costa & McCrae, 1992) have been mixed, with some Neuropsychological Assessment of Patients 237 studies identifying no differences between patients with chronic pain and normal controls (Wade, Dougherty, Hart, & Cook, 1992). Several more recent studies have found support for the consideration of several of the “big five” personality domains (openness to experience, conscientiousness, extraversion, agreeableness, and neuroticism) as related to emotional functioning, pain catastrophizing, and reported pain intensity. For example, studies involving patients with fibromyalgia have found increased pain catastrophizing, pain anxiety, and pain preoccupation with associated elevations in neuroticism, conscientiousness, and agreeableness, and lower scores in openness (Martinez, Sanchez, Miro, Medina, & Lami, 2011; Torres et al., 2013). Goubert, Crombez, and Van Damme (2004) postulated neuroticism as a vulnerability factor, such that higher levels of neuroticism result in greater perception of pain threat and therefore, more pain catastrophizing. Eleva- tions on the neuroticism scale have also been correlated with greater levels of pain catastrophizing, depression, and pain severity at pre, post, and follow-up time points in a large sample (n = 966) of patients who participated in an interdisci- plinary chronic pain rehabilitation program (Hayes, Bretz, Townsend, Luger, & Hooten, 2012). In this same study, participants scoring low on agreeableness were more likely to terminate early from the pain program.

Minnesota Multiphasic Personality Inventory-2-RF The Minnesota Multiphasic Personality Inventory-2 (MMPI-2; Butcher et al., 1989) and the MMPI-2-Restructured Form (MMPI-2-RF; Ben Porath & Tell- egen, 2008) are familiar to most neuropsychologists as invaluable tools in clinical and forensic assessments. The primary drawback of the MMPI has always been its length, which was remedied significantly by the MMPI-2-RF revision, reducing the number of items by approximately 40%. The body of literature amassed on the various versions of the MMPI is vast and the number of scales developed over the years is easily in the hundreds. The MMPI-2-RF introduces a number of new scales, including validity scales with a high level of somatic focus, highlighting the importance of assessment of the nature of pain and somatic symptoms. A brief summary of these measures is provided next. Over the years, many MMPI validity scales were developed to assist with determining the interpretability of the MMPI profile. In the MMPI-2-RF there are nine validity scales and the Cannot Say (CNS; the number of items not answered) scale (Ben-Porath, 2012). Two of these scales emerged largely from the neuropsychology and forensic literatures and assess for over-report of cognitive and physical symptoms (FBS-r and RBS), and another scale examines the reporting of infrequently endorsed physical complaints (Fs). The Symptom Validity (FBS-r) scale includes 30 of the original 43 items from the Fake Bad Scale (Lees-Haley, English, & Glenn, 1991) and has been shown to be a strong index of noncredible responding in general. Many of the items are somatically oriented and high scores suggest over-reporting of symptoms, particularly those comprising the Somatic/ 238 Greg J. Lamberty et al.

Cognitive Scales (Ben-Porath, 2012). The Response Bias Scale (RBS; Gervais et al., 2007) was developed in a forensic evaluation setting and has been found to be sensitive to noncredible memory or cognitive concerns. Finally, Infrequent Somatic Responses (Fs) was developed to assess the credibility of somatic symptom reporting, including pain. High scores (T > 100) on Fs suggest that the Somatic Scales are not likely interpretable (Ben-Porath, 2012). Among the Substantive Scales from the MMPI-2-RF are several somatically focused indices. Somatic Complaints (RC1) is the Restructured Clinical (RC) scale that assesses the reporting of general somatoform symptomatology. Elevations on RC1 are often associated with elevations on several of the Specific Problem scales that assess somatic and/or cognitive difficulties. Ben-Porath (2012) suggests that the Somatic/Cognitive scales should be interpreted relative to scores obtained on the three validity scales described earlier (Fs, FBS-r, RBS). He notes that while Fs elevations cannot determine whether a subject is willfully over- reporting, T-scores greater than 100 suggest that there is not likely a reasonable physical explanation for the findings and the Somatic/Cognitive Scales should not be included in the interpretive report. Specific Problems Scales are a new addition to the MMPI-2-RF and include Somatic/Cognitive, Internalizing, Externalizing, and Interpersonal Scales. These scales tend to be associated with the various RC scales, but are brief and more focused. The Somatic/Cognitive Scales are of particular relevance to neuropsychologists, and in the context of evaluating patients with pain disorders. Briefly, Malaise (MLS), Head Pain Complaints (HPC), Neurological Complaints (NUC) and Cognitive Complaints (COG) will likely provide helpful information about the specific nature of a patient’s physical and cognitive concerns (Ben-Porath, 2012). There is scant literature examining the presentation of patients with pain disorders on the Somatic/Cognitive Scales as yet, but certainly descriptive clinical information about the nature of patients’ concerns can be gleaned from a review of these scales. The clinical case at the end of this chapter includes MMPI-2-RF data and provides an example of its clinical utility.

Neurocognitive Aspects of Chronic Pain Patients with chronic pain frequently report cognitive concerns that interfere with their daily life. Among the most common complaints are difficulties with attention, concentration, and memory/forgetfulness (Iverson & McCracken, 1997; Kreitler & Niv, 2007). These concerns typically bear no direct relationship to chronic pain. That is, there is no widely accepted underlying neural mechanism through which the experience of chronic pain might also adversely impact cognitive functioning. Research investigating cognition in chronic pain has increased in recent years, likely related to its pervasive negative impact on quality of life and general health. Establishing neurocognitive patterns associated with chronic pain is important not only to understand how these difficulties impact patients’ daily functioning but also how they may compromise engagement in treatment. Neuropsychological Assessment of Patients 239

Neuropsychological assessment in chronic pain populations is complicated by variable findings in studies seeking to assess the effects of pain on cognitive functioning. Several studies have failed to find differences in cognitive performance between pain and control groups after accounting for psychosocial factors (Brown et al., 2002; Landrø, Stiles, & Sletvold, 1997). In contrast, other studies have shown deficits on tests of attention, processing speed, memory, and executive function in pain patients relative to controls (see Ambrose, Gracely, & Glass, 2012; Hart et al., 2000; Libon et al., 2010; Sjøgren et al., 2005). Given the complexity of the clinical presentation in pain disorders and the heterogeneous nature of this population, it is not surprising that the literature fails to identify a specific pattern of neurocognitive difficulties. In summarizing the neuropsychological literature on fibromyalgia, Suhr and Spickard (2007) noted, “for any study finding impairment in a particular neuropsychological construct or with a specific neuropsychological measure, one can find another study that did not find impairment in that construct or with that measure” (p. 261).

Inconsistency in the Pain and Cognition Literature Many factors contribute to the variable findings in the neuropsychological literature examining chronic pain samples. One such factor is the wide range of methodologies employed. For instance, studies vary in terms of patient and test selection, the definition of cognitive impairment, and the extent to which con- founds (such as comorbid diagnoses) are accounted for (Lamberty, 2008). Depres- sion, anxiety, and fatigue have significant impact on cognitive efficiency and memory, and disentangling these effects from pain is a complex endeavor (Lew et al., 2009). Cognitive effects of pain medication on opiate naïve patients without chronic pain have included slowed motor function and reaction time (Kerr, Hill, Coda, & Calogero, 1991; Zacny et al., 1994), while results for individuals with chronic pain have been mixed. It has been suggested that long-term opioid use may reduce cognitive impairment by relieving pain and activating the nervous system (see Jamison et al., 2003). In contrast, a recent meta-analysis demonstrated that chronic opioid use was associated with impairment in verbal working memory, cognitive impulsivity (risk taking), and verbal fluency (Baldacchino et al., 2012). Methodological flaws and inconsistencies have contributed to variable findings in the literature, making meta-analytic approaches dubious (Baldacchino et al., 2012). Individuals’ perceptions about their cognitive difficulties may contribute to variability in neuropsychological findings in pain samples. The concept of “cogniphobia” suggests that individuals may avoid tasks that they believe will trigger pain, and consequently results in diminished effort on cognitive tasks perceived as demanding (Martelli, Zasler, Grayson, & Liljedahl, 1999). Research in cogniphobia has demonstrated that individuals with greater pain-related fear perform worse on cognitive tasks (Martelli, Zasler, Grayson, & Liljedahl, 1999), even without the influence of secondary gain and after accounting for individuals who failed performance validity testing (Suhr & Spickard, 2012). 240 Greg J. Lamberty et al.

Effort and Performance Validity Findings Recent neuropsychologically oriented studies have highlighted the finding that inconsistent cognitive performance observed in patients with pain may in part relate to variable control of effort. Despite recommendations for incorporating effort assessment in clinical pain populations (Martelli, Zasler, Bender, & Nichol- son, 2004), the majority of early studies examining pain and cognition did not include performance validity tests (PVTs). Absence of PVTs is particularly prob- lematic as research indicates high rates of PVT failure in patients with fibromyalgia (Gervais et al., 2001, 2004; Johnson-Greene et al., 2013; Suhr, 2003), CRPS (Greiffenstein et al., 2013), and chronic pain (Meyers & Diep, 2000). Rates of symptom exaggeration or frank “malingering” tend to increase in the context of litigation (Bianchini, Greve, & Glynn, 2005; Gervais et al., 2004), though PVT testing is also warranted in routine contexts to assure interpretable data. Effort may vary or be insufficient for a multitude of reasons. In non-litigating contexts, practitioners need to be vigilant regarding the potential for secondary gain, as patients are not always forthcoming with this information or may not perceive its influence on their motivational state. More generally, level of pain preoccupation may interfere with task engagement, resulting in suboptimal or variable effort.

Assessment Recommendations Considering the foregoing, the task of assessing all potential contributing factors in the cognitive presentation of patients with pain may seem daunting. However, clinical neuropsychologists are well-equipped to address the complexity of cognitive complaints reported by patients with pain disorders. Neuropsychologists are often asked to distinguish among a range of medical and psychiatric comorbidi- ties with pain being one such comorbidity. In the modal clinical evaluation, the process of test/measure selection in a case involving a pain disorder diagnosis does not differ markedly from other complex clinical populations. Flexibility is required, as most neuropsychologists have limited time to collect their interview and test data. Strategies for optimizing task engagement are also important considerations. Next we offer some general suggestions for how to approach assessment for patients with chronic pain disorders.

• Pain assessment measures may be given at the outset to help the neuropsychologist better determine potential overlay of psychiatric factors if this is unclear from the interview and record review. • During the clinical interview, clinicians should clarify possible influence of medication effects by asking questions related to types of medications used (prescribed and over-the-counter), use on day of evaluation, and potential for addiction/misuse; confirmation of self-report with records and labs is also recommended. Neuropsychological Assessment of Patients 241

• Following the clinical interview, neuropsychologists must choose to optimize neurocognitive versus psychological assessment depending upon what they perceive to best account for the current symptom presentation. • Administration of a cognitive screening battery plus an MMPI-2-RF may be the best approach for a patient who presents with a long-standing history of neuropsychiatric or personality issues/diagnoses. • Conversely, a more comprehensive cognitive baseline battery with additional psychological screening instruments would be indicated for a patient with an unremarkable psychiatric history. • During the assessment, clinicians should monitor patients regarding level of fatigue, pain, and so forth, and provide breaks accordingly to optimize moti- vation and effort. • Clinicians should also attend to patients’ remarks or ask them about the perceived difficulty of various tasks and any consequences for their pain to gauge the potential influence of cogniphobia on test performance (Suhr & Spickard, 2012).

Case Presentation

Mr. N was a 54-year-old, left-handed, divorced, white male referred for neuropsychological evaluation secondary to concerns about general cognitive inefficiency that had reportedly evolved slowly since he experienced a fall at home approximately 10 years prior to the exam. At the time of the evaluation, Mr. N had been unemployed for 5 years. As a result of the fall, the patient stated that he experienced trauma to his shoulders and head, and injured his neck and back. He also fractured two fingers on his left hand. Mr. N recalls having experienced some somnolence and cognitive inefficiency following the accident though he returned to work shortly afterward. He eventually found it impossible to work because of chronic pain, an extensive pain management regimen, and perceived cognitive difficulties. There were no emergency room records to review and the patient had no previous neuropsychological evaluations. The present evaluation occurred approximately 13 years after the accident. Medical and developmental histories were reported to be unremarkable through the patient’s mid-thirties. Mr. N had some mild attention difficulties during grade school, but earned good grades in high school, undergraduate studies, and a graduate engineering program. Mr. N was diagnosed with adult attention deficit disorder in his early forties and also struggled with depression and anxiety symptoms throughout 242 Greg J. Lamberty et al.

his adulthood. Symptoms were treated pharmacologically mostly by primary care providers, with no counseling or psychotherapy. While he basically denied a history of psychiatric treatment, records indicated that the patient followed with a psychiatrist for approximately five years (with that treatment ending about four years prior to the neuropsychological assessment). Treatment was provided for major depression and attention deficit disorder with Zoloft and Adderall. Cel- exa was eventually settled upon as the most effective antidepressant medication, and he was taking this at the time of the evaluation. There were no reported issues with alcohol or other substance abuse. Other health issues included obstructive sleep apnea (OSA), erec- tile dysfunction, bilateral knee pain, and hypertension. Over the years, sleep difficulties were treated with many different medications including Ambien, Halcion, Lunesta, Nuvigil, and Remeron—none of which was regarded as having been very helpful. Mr. N’s sleep issues were extensively evaluated and treated by multiple providers, both before and after the patient’s psychiatric treatment, and prior to the accident that resulted in his pain concerns. Treatments included multiple medications for sleep difficulties (as noted earlier), periodic limb movement disorder (Mirapex), and uvulectomy for snoring and OSA. Most notable in Mr. N’s presentation and medical history was his pursuit of care for pain in his neck, shoulders, back, and head following the accident. Upon interview the patient described elaborate rituals for managing his pain that involved taking medication, stretching, walk- ing, use of a transcutaneous electrical nerve stimulation (TENS) unit, resting, avoiding certain kinds of foods, limiting cognitive activities, and attending appointments with different therapists and providers. Under- lying all of these management strategies was a built-in contingency for rest if he “overdoes it.” Aside from his daily routine, he described in great detail procedures that he has gone through to “tweak” the pain management regimen, including specific nerve blocks, radio frequency ablations, rhizotomy, ultrasound, and steroid/cortisone injections. The general sense conveyed was that his pain and the management of it was an encompassing pursuit that took up most of his time. A neuropsychological evaluation was completed and included the Pain Catastrophizing Scale (PCS) and the MMPI-2-RF. There were no neurocognitive deficits noted and Mr. N had a full-scale IQ in the supe- rior range. Despite general protestations regarding the difficulty of some tasks and the taking of frequent breaks to stretch and use the restroom, Mr. N tolerated the lengthy assessment well and passed all performance validity measures. Neuropsychological Assessment of Patients 243

Responses on the PCS suggested a high overall level of pain catastrophizing (Total score = 32, 80th percentile). The Rumination subscale was substantially elevated (Rumination = 14, 91st percentile), as was the Magnification subscale (Magnification = 8, 90th percentile). Helplessness was relatively lower (Helplessness = 10, 60th percentile), suggesting a level of adjustment to what remained a very high level of worry and concern about pain. Data from the PCS user manual indicates that among those with a Total score of greater 30 (75th percentile), 70% remain unemployed 1 year postinjury, and 70% describe themselves as “totally disabled” (Sullivan, 2009). A review of the MMPI-2-RF validity scales indicates that the profile was valid and interpretable (Figure 8.1). Elevations on FBS-r and RBS suggest a high level of unusual symptom acknowledgement, but not at a level that invalidates the profile. Further, the Infrequent Somatic Responses scale (Fs) was within normal limits, indicating that the Somatic/Cognitive scales could be interpreted. There were no elevations among the Higher Order scales, and only RC1 (Somatic Complaints) was elevated among the Restructured Clinical

MMPI-2-RF Validity Scales

120 110 100 90 80 70 60 50 40 30 20 VRIN-r TRIN-r F-r Fp-r Fs FBS-r RBS L-r K-r

FIGURE 8.1 MMPI-2-RF Validity Scales T-scores. VRIN-r = Variable Response Inconsistency-revised; TRIN-r = True Response Inconsistency- revised; F-r = Infrequent Responses-revised; Fp-r = Infre- quent Psychopathology Responses-revised; Fs = Infrequent Somatic Responses; FBS-r = Symptom Validity-revised; RBS-r = Response Bias Scale-revised; L-r = Uncommon Virtues- revised; K-r = Adjustment validity-revised. 244 Greg J. Lamberty et al.

scales, suggesting a high level of physical discomfort, preoccupation with somatic symptoms, and concerns about disability (Figure 8.2). Examination of the Somatic/Cognitive scales shows elevations for malaise, head pain, neurological, and cognitive complaints (Figure 8.3). The elevation of these scales, while clinically notable, is relatively mod- est compared to that seen in individuals with broader somatoform complaints. The remainder of the profile was fully within normal limits. MMPI-2-RF results were largely consistent with behavioral observa- tions and diagnostic impressions. That is, Mr. N was primarily focused on pain, what pain meant to him, and how it adversely affected his life and ability to work. There was relatively little exaggeration of other difficulties that is often seen in individuals with broader somatoform presentations. Further, the lack of significant issues with symptom and performance validity suggests that Mr. N has focused his attention and efforts on managing and reducing his pain. Indeed, he feels like he has successfully done so, refining his approach over many years. While he reported cognitive difficulties, Mr. N’s performance across a range of neuropsychological measures was quite strong. Mild relative weak- ness (average or low average performances) was noted on a couple of

MMPI-2-RF Higher-Order (H-O) and Restructured Clinical (RC) Scales 120

110 Higher-Order Restructured Clinical 100 90 80 70 60 50 40 30 20 EID THD BXDRCd RC1RC2 RC3RC4 RC6RC7 RC8RC9

FIGURE 8.2 MMPI-2-RF Restructured Clinical (RC) Scales. RCd = Demor- alization; RC1 = Somatic Complaints; RC2 = Low Positive Emo- tions; RC3 = Cynicism; RC4 = Antisocial Behavior; RC6 = Ideas of Persecution; RC7 = Dysfunctional negative Emotions; RC8 = Aberrant Experiences; RC9 = Hypomanic Activation. Neuropsychological Assessment of Patients 245

MMPI-2-RF Somatic/Cognitive Scales

120 110 100 90 80 70 60 50 40 30 20 MLS GIC HPC NUC COG

FIGURE 8.3 MMPI-2-RF Somatic/Cognitive Scales T-scores. MLS = Malaise; GIC = Gastrointestinal Complaints; HPC = Head Pain Com- plaints; NUC = Neurological Complaints; COG = Cognitive Complaints. isolated memory tasks, and was consistent with his reported concerns. All PVTs were well above recognized cutoff scores for suspect effort. During feedback, Mr. N acknowledged an understanding of the mind–body connection but had clearly developed an elaborate system that validated his belief in the disabling nature of his pain. This was true despite a general and wide-ranging lack of diagnostic evidence for more significant orthopedic findings that would have hastened recommendations for surgery. His beliefs were inarguably facilitated by numerous providers who persisted in offering different treatments and procedures for his chronic pain, including daily opiate medications for over 10 years. Finally, it was notable that Mr. N had not engaged in any kind of psychotherapy or psychoeducation. He took some yoga classes and con- tinued visits with physical therapy, but mostly for the modalities used to treat specific pain complaints. The patient was generally resistant to the notion that psychotherapy was likely to be of any benefit. Provid- ers, from primary care treaters to specialists in pain medicine, validated Mr. N’s very strong beliefs about the nature and severity of his pain issues over the years. They reified the notion that his pain was related to specific pathology, was severe, and was disabling. In contrast, Mr. N’s beliefs about his cognition were not yet so ingrained and provided an opportunity to work on a more conservative approach to managing clinical difficulties and improving coping and general mental health. 246 Greg J. Lamberty et al.

Summary Chronic pain is a commonly reported clinical issue in individuals referred for neuropsychological evaluation. Diagnoses including fibromyalgia and CRPS are claimed by patients and referral sources to be diagnostically and etiologically distinctive, though there is little in the neuropsychological literature to support such contentions. In contrast, personality and symptom measures can facilitate the description of patients with pain disorders and help to track progress in treatment and longitudinal outcomes. Many of the measures described in this chapter were developed by clinicians treating patients with pain disorders and they have not been routinely used in traditional neuropsychological assessment contexts. Neuropsychologists can utilize these measures, but care must be taken to clarify the nature of the assessment being conducted. As always, there is an opportunity for neuropsychologists to lead the way in standardizing the use of pain-specific measures in the context of neuropsychological practice.

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