Patients with chronic pain who have a mood disorder are likely to be prescribed opioids more often than those without a mood disorder, which can lead to doctor-patient conflicts. In a study of 50 Veterans Administration (VA) patients and 50 patients treated in outside primary care practices with opioids for noncancer pain, Reid and colleagues³⁶ found a 50% prevalence of major depression and a 20% prevalence of an anxiety disorder. In a similar study, Breckenridge and Clark³⁷ determined a high prevalence of mood disorder among patients with pain who were prescribed opioids. In a study of 191 patients examining factors that led pain physicians to prescribe opioids for noncancer pain, Turk and Okifuji³⁸ concluded that neither pain severity nor objective physical pathology influenced the decision to prescribe. Rather, greater affective distress and pain behaviors drove the decisions. Thus, patients with chronic pain and psychopathology are likely to be prescribed opioids, and these patients report greater pain intensity, more pain-related disability, and a larger affective component to their pain than those without psychopathology.³⁹

In terms of the impact of mood disorders on opioid response, a study examined the effects of intravenous (IV) opioid analgesia in patients with chronic pain with high and low levels of psychiatric comorbidity.⁴⁰ Sixty patients with low back pain stratified into three groups of severity of psychological symptoms (low, moderate, and high) were given IV morphine and placebo in random order on separate visits and completed pain ratings over 3 hours at each session. The low-psychopathology group had a 40% greater reduction in pain with IV morphine than the high-psychopathology group (P < .01). This study found that patients with chronic pain who had a high degree of negative affect benefited less from opioids in controlling their pain than those with a low degree of negative affect, a finding replicated by subsequent studies.⁴¹

Not all patients with difficult behavior exhibit significant psychopathology, such as major depression or anxiety or a personality disorder. Patients who are otherwise “normal” can be perceived as difficult, for example, when they arrive at a pain center for treatment with unrealistic expectations about what should happen. They may have had problems with previous health care settings in which they were accused of exaggerating their pain. Lack of sleep, extreme fatigue, poor eating habits, and long travel to their appointments can also contribute to volatile and unstable behavior. They may experience their physicians as dismissive or skeptical of their pain rather than being understanding and sympathetic. Even comparatively well-adjusted patients can sometimes develop the idea that their pain physician should be able to eliminate all of their pain and that failure to do so is tantamount to withholding treatment. This becomes critical when medication regimens involving opioids are concerned. Patients may worry about being prescribed adequate amounts of medication or undergoing withdrawal if they are to be tapered off opioids.

Some patients with pain are entitled consumers who are no longer willing to be passive in their treatment but rather prefer to take control of their medical care. Medical information through the Internet is more accessible than ever, and patients frequently come to their appointments armed with information about a particular therapy. Patients are increasingly opinionated about their care. They look to have a mutually respectful relationship with their health care providers and want to take an active role in the decision-making process. They become dissatisfied with their treatment when their provider is unresponsive to their suggestions and not willing to hear their own ideas. Cultural and ethnic differences can also act as barriers to an effective doctor-patient relationship.⁴²

Most persons with chronic pain also have significant medical conditions that impact treatment decisions. Some are medically challenging as well as being interpersonally difficult. Patients with pain may report asthma, chronic obstructive pulmonary disease (COPD), diabetes, coronary artery disease, hypertension, ulcers, kidney, bladder and liver problems, and history of cancer. Persons with chronic pain often smoke cigarettes, have gained weight, and have lost bone density. Multiple providers can prescribe multiple medications including blood thinners, blood pressure and heart disease medications, inhalers, and antidepressants. These patients are also noted for allergies and reactions to certain medications. Occasionally, they have implanted medical devices (e.g., pacemakers, rods, stimulators) or wear prostheses. Some of the most challenging patients tend to be older, take many medications, have multiple psychosocial problems, have poor social support, limited education, and come from disadvantaged backgrounds.³

Kenny⁴³ points out in a survey study of 20 patients with chronic pain and 22 pain specialists that differences in communication interactions—especially when patients embrace a medical model to explain their pain and physicians perceive
a psychogenic etiology of pain—can significantly negatively affect the doctor-patient relationship. In a study of how and why physicians dismiss patients from their practice, 25 general practitioners identified two types of patients who tend to be dismissed over others: (1) patients who break the rules of the doctor-patient relationship or clinic practice and (2) patients whose difficult personality makes it hard to care for them.⁴⁴

There are notable links between chronic pain and substance abuse.^45,46 Studies show that 10% to 16% of patients treated in a general practice and 25% to 40% of hospitalized patients have problems related to drug or alcohol addiction.^47,48 Other studies indicate that patients with pain and high rates of mood disorders are at high risk for alcohol or opioid abuse.^49,50,51 Hasin and Liu⁵² found some patients abuse opioid pain medication in an attempt to alleviate their psychiatric symptoms. Thus, comorbid depression and/or anxiety disorders are associated with greater opioid misuse, even in those with no history of a substance use disorder. Wasan and colleagues⁵³ also found that increased craving for prescription opioids was associated with a greater urge to self-medicate the anxiety and depression that precede the sensations of craving. These individuals with a mood disorder who self-medicate negative affective symptoms are at increased risk for substance abuse.^51,54 Physicians are often in the difficult position of providing appropriate pain relief while minimizing the inappropriate use of pain medications by being ever watchful of substance use disorders.⁵⁵ Inappropriate use can include the following: selling and diverting prescription drugs, seeking additional prescriptions from multiple providers, concurrently using other illicit drugs, and manipulating the formulation to snort or inject the medications or use them in a manner in which they were not intended. It is important for the successful treatment of chronic noncancer pain to be able to frequently monitor patients on opioid regimens and to identify those patients who exhibit ongoing abuse behaviors, which can be an added burden to providers.^56,57