Several risk factors predispose cancer patients to develop depressive disorders: Social isolation. Recent losses. ■ A tendency to pessimism. ■Socioeconomic pressures. A history of mood disorder. ■ Alcohol or substance abuse. ■ Previous suicide attempt(s). ■ Poorly controlled pain. The depressed patient with cancer must be assessed for suicidal risk. Suicidal risk factors include: A prior psychiatric diagnosis (especially depression). ■ Increasing age. Family history of suicide. Poor social support. ■ Delirium. ■ Advanced disease. ■ Disfiguring disease or surgery. ■Substance abuse. ■ Poorly controlled pain. Many drugs used to treat cancer are associated with depressed mood as a side effect (Lesko, Massie, and Holland, 1987). The practitioner is also advised to consider other concurrent medical conditions, medications, and uncontrolled pain, all of which can contribute to depressed mood, especially in the elderly. The prevalence of clinical depression in cancer patients ranges from 5 to 50 percent. The most systematic study of psychiatric disorders in ambulatory patients with cancer (200 patients) found that 53 percent were coping well and did not have a formal DSM-III diagnosis (American Psychiatric Association, 1980). Of the remaining 47 percent, 68 percent had an adjustment disorder; 13 percent had major depressive, dysthymic, or bipolar disorder; and 19 percent had organic mental, personality, or anxiety disorders. Adjustment disorders with depressed mood and major mood disorders were the most common psychiatric disorders identified in cancer patients. The highest rates of clinical depression are in those with advanced cancer and with a greater level of disability and discomfort. One study found that 77 percent of bedridden patients met criteria for major depressive syndrome, compared to only 23 percent of functionally independent patients (Bukberg, Penman, and Holland, 1984). Most studies suggest that 20 to 25 percent of cancer patients suffer major depression at some point during their illness. These percentages are remarkably similar to the rates of depression associated with other medical illnesses and a similar level of physical functioning. The finding that patients with cancer do not evidence a greater rate of major depression than do those with other medical disorders invalidates the common, but incorrect, assumption that persons with cancer should be depressed-an assumption that contributes to underdiagnosis and undertreatment of these depressions. Chronic Fatigue Syndrome Guideline: Nearly all depressed patients complain of fatigue and low energy. This symptom is associated with a 46 to 75 percent lifetime rate of major depressive disorder. Complaints of chronic fatigue must be differentiated from the formal chronic fatigue syndrome. (Strength of Evidence = B.) Only a small minority of patients with complaints of chronic fatigue meet the Centers for Disease Control (CDC) criteria for chronic fatigue syndrome. When the patient meets criteria for major depression, dysthymia, or other formal mood syndromes, the mood syndrome is diagnosed. The complaint of chronic fatigue per se is insufficient for the diagnosis of chronic fatigue syndrome. The symptom of chronic fatigue (not the syndrome) is the seventh most common complaint among adult patients in primary care settings and may be a significant problem in as many as 20 to 25 percent of these patients. Studies of patients with chronic fatigue symptoms reveal lifetime rates of psychiatric disorders in the 50 to 77 percent range, based on structured psychiatric interviews. In all studies, major depressive disorder was the most commonly reported illness (lifetime rates ranging from 46 to 75 percent). These studies also found that various anxiety disorders and somatization disorder occurred in 15 to 40 percent of patients with chronic fatigue symptoms (Hickie, Lloyd, Wakefield, et al., 1990; Kroenke, Wood, Mangelsdorff, et al., 1988; Kruesi, Dale, and Straus, 1989; Manu, Lane, and Matthews, 1988; Manu, Matthews, and Lane, 1988). Most studies that examined the temporal sequence of chronic fatigue symptoms found a 50 to 90 percent onset rate of psychiatric illness (most commonly, major depressive disorder) prior to the onset of chronic fatigue symptoms (Kruesi, Dale, and Straus, 1989; Manu, Matthews, and Lane, 1988). While the central feature of chronic fatigue syndrome is persistent, excessive fatiguability, it must be accompanied by various other somatic and psychological symptoms, including aching muscles and joints, headache, sore throat, painful lymph nodes, muscle weakness, sleep disturbance, mental fatigue, difficulty in concentrating, emotional lability, and sadness. In chronic fatigue syndrome, the somatic and fatigue complaints are out of proportion to physical and laboratory findings. According to the CDC criteria, the presence of a diagnosable formal psychiatric disorder, such as major depressive or dysthymic disorder, excludes the diagnosis of chronic fatigue syndrome. That is, patients who present with the formal symptomatic CDC criteria for chronic fatigue syndrome and who also meet the criteria for a formal mood disorder are treated for the mood disorder. Whether this mood disorder is etiologically connected to the chronic fatigue syndrome or whether it is an independent illness is unclear. Fibromyalgia Guideline: As with other medical conditions, patients with fibromyalgia may or may not have clinical depression. If present, it should be diagnosed and treated as a separate entity. (Strength of Evidence = B.) Fibromyalgia (fibrositis) is a syndrome of diffuse, aching, musculoskeletal pain associated with chronic insomnia, daytime tiredness, morning stiffness, dysesthesia in the hands, and symptoms of irritable bowel type. The American College of Rheumatology has published the currently accepted criteria for the diagnosis of fibromyalgia (Wolfe, Smythe, Yunus, et al., 1990). Two studies have compared fibromyalgia and rheumatoid arthritis patients in structured psychiatric interviews. In one, patients with fibromyalgia had significantly higher rates of lifetime major depressive disorder than did rheumatoid arthritis patients (71 versus 14 percent), and they had significantly more first-degree relatives with mood and anxiety disorders (Hudson, Hudson, Pliner, et al., 1985). The second study also found higher rates of mood disorders in patients with fibromyalgia than in those with rheumatoid arthritis (20 versus 8.7 percent). Statistical significance was not attained, probably because of the small sample size (Alfici, Sigal, and Landau, 1989). Guideline: Depression Associated 5 with Medications Various medications have long been reported to cause or to be associated with mood symptoms or formal disorders as side effects. The development of depression in some patients taking reserpine formed one of the bases for the biologic theories of depression. Most of the evidence rests on case reports of medications "causing" mood symptoms. Table 7 lists those agents reported to have been associated with depression in some patients. It is essential to recognize that idiosyncratic reactions to medications do occur. Even without data to suggest a causal relationship between a drug and mood symptoms, good clinical judgment dictates that it should be stopped or changed if a patient develops depression after beginning use. However, such an event does not suggest that the particular medication should not be used in other patients who appropriately require it, but may Cycloserine agents Ethambutol Disulfiram Anti-Infective Agents Nonsteroidal anti-inflammatory Cocaine (withdrawal) (++) Others Amphetamines (withdrawal) (++) L-dopa (±) Cimetidine Ranitidine Sulfonamides Baclofen Note: These medications have been reported to induce depression in some cases. Not everyone receiving one of these will necessarily be depressed. The cause of depression in a depressed person receiving treatment is not necessarily the medication. This list indicates some medications that should be evaluated as possible causes of depression in particular patients. The degree of certainty of a causal relationship is shown in parentheses for selected drugs. Source: Derived from Popkin MK. "Secondary" syndromes in DSM-IV: a review of the literature. In: Frances AJ, Widiger T, editors. DSM-IV sourcebook. Washington, DC: American Psychiatric Press; in press. |