Strategies for treating depression in patients with hepatitis C

CASE CONTINUED: Motivated and compliant

Since joining the MMTP 6 months ago, Mr. P has been motivated and compliant with all appointments and treatments. Routine urine toxicology screening supports his claim of abstinence. Mr. P begins HCV treatment while continuing follow-up with addiction medicine and psychiatric clinicians and maintains open communication with all treatment providers.

For many years the standard HCV treatment was pegylated interferon-α (IFN-α) and ribavirin. IFN-α is a proinflammatory cytokine with antiproliferative, antiviral, and immunoregulatory properties. The half-life of IFN-α significantly increases with pegylation, which allows for weekly injections.^10,11 IFN-α usually is combined with ribavirin, which increases its efficacy as measured by the sustained virological response (SVR) compared with IFN-α alone. Depending on the virus genotype, treatment lasts 24 to 48 weeks; SVR rates range from 40% to 82%.^11-13 In 2011, the FDA approved 2 agents—telaprevir and boceprevir—for adjunctive treatment of HCV genotype 1 infection. These 2 agents are protease inhibitors that when added to IFN-α and ribavirin increase the SVR rate in genotype 1 infection from 40% to 50% to approximately 75%.^14,15

Although the neuropsychiatric side effects of telaprevir and boceprevir have not been determined, treating chronic HCV with IFN-α and ribavirin has been associated with multiple psychiatric symptoms, including depression, mania, suicidality, anxiety, and psychosis.^11-14 Psychiatric symptoms are a common reason for discontinuing or reducing HCV treatment. Because of the high frequency of neuropsychiatric complications, some clinicians believe HCV patients with preexisting affective, psychotic, or substance use disorders should be excluded from HCV treatment. This has led to many HCV patients being untreated despite a lack of prospective, controlled data to support this opinion.¹² To improve outcomes and decrease morbidity, providing appropriate psychiatric services appears to be more important than attempting to select lower-risk patients for antiviral therapy.^1,12,16 The goals of psychiatric treatment should be to alleviate symptoms and allow patients to complete IFN-α therapy without interruption.^16,17

Studies of high-risk patients who attend multidisciplinary treatment programs that can monitor adherence and efficacy and control side effects before and during HCV treatment have found psychiatric patients have similar adherence, compliance, and SVR rates and were not at increased risk of worsening depressive or psychotic symptoms compared with patients without a psychiatric history.^12,18 Additionally, HCV patients with a psychiatric history are not at an increased risk of suicide.^13,16 Similar findings have been observed in patients with active IV drug use or those receiving opioid agonist therapy. When HCV and substance use are treated simultaneously, patients can successfully complete HCV treatment with SVR rates comparable to those of patients not receiving opioid agonist therapy.^19-21

CASE CONTINUED: Worsening symptoms

During a psychiatric follow-up 12 weeks after starting HCV treatment, Mr. P reports worsening depressive symptoms with low mood, decreased enjoyment of activities, poor sleep, low appetite, and fatigue. He shows no evidence of psychosis and denies suicidal ideation. We continue his HCV treatment, schedule more frequent psychiatric visits, and initiate citalopram, titrated to 40 mg/d.

Depressive symptoms, the most common neuropsychiatric manifestation of HCV, typically begin early in treatment, usually within the first 12 weeks. Two distinct symptom clusters are noted. A neurovegetative cluster characterized by reduced energy, anorexia, and psychomotor retardation typically begins within the first few months of treatment. Months later, a depression-specific syndrome appears that includes depressed mood, anxiety, and cognitive impairment.²²

Depressive symptoms may occur in up to 60% of patients treated with IFN-α.¹¹ When more rigorous depression measures are used, rates decrease to approximately 20% to 30%.^11,13 Accurate diagnosis and treatment of emerging depressive symptoms is essential because untreated depression can lead to postponing or excluding patients from antiviral treatment.² Screening instruments such as the Beck Depression Inventory-Second Edition (BDI-II) can be used to measure depressive symptoms in HCV patients with high sensitivity. However, because specificity has been low and somatic symptoms of chronic illness and depression often overlap, the BDI-II and other inventories may overestimate depression. Some researchers have suggested that focusing on questions targeting cognitive and affective symptoms rather than somatic ones may be a more valid measure of depression in patients undergoing immunotherapy for HCV.²

The immune system is implicated in IFN-α-induced depression because depressive symptoms share many features with a constellation of somatic and behavioral symptoms termed “sickness behavior.”¹¹ These behaviors can occur when patients are exposed to cytokines that lead to a depressed level of functioning, which may allow the body to devote more energy to fighting illness. IFN-α, a cytokine, stimulates the immune system, which can lead to increases of interleukin (IL)-2, IL-6, and IL-10. Increased circulating levels of these ILs have been correlated with higher depression scores. Additionally, studies have found that patients who develop depression during IFN-α treatment have higher SVR rates, suggesting a more robust immune response.^11,22 For a discussion of how serotonin metabolism and genetic polymorphisms also may help explain the prevalence of depression in patients with HCV, see Box 2.