The next assessment centers on his depression. Although bereavement is a possibility in the differential diagnosis, the extent and duration of his symptoms are consistent with major depression. Treatment of major depression in HIV/AIDS has been widely studied throughout the AIDS epidemic. The estimate of the lifetime prevalence of major depression in persons with HIV is 50%, greatly exceeding that of the general population. Medication management of depression usually results in 60-70% response within four to eight weeks and remission in eight to 12 weeks. Patients and clinicians alike often have expectations of faster outcomes. Antidepressant selection in HIV/AIDS patients is simpler than other psychotropic classes. Most selective serotonin reuptake inhibitors (SSRIs) and tricyclics (TCAs) have shown similar efficacy and side effect profiles to the general population. Although mild interactions between ritonavir-containing regimens and some antidepressants may occur, (generally leading to increased levels of the antidepressants) most clinicians should feel comfortable and safe in starting an antidepressant in this otherwise stable HIV patient. Since efficacy is essentially equivalent in the spectrum of antidepressants, formulary availability and side effect profiles usually dictate the selection. Drug selection is less important than duration of treatment. Antidepressant medications should be continued for at least six to nine months after remission of the depressive symptoms. The patient should be monitored for the development of side effects initially every two weeks and effectiveness of treatment assessed eight to 12 weeks after starting antidepressant therapy. Continued follow-up every three to four months thereafter is standard.
In addition to the challenge the dual diagnoses of HIV and major depression present to this patient, as well as his clinicians, HCV co-infection further complicates the situation. Interferon used in the treatment of HCV infection can exacerbate depression. However, a history of depression is not an absolute contraindication for HCV therapy and patients with well controlled depression may be candidates for such treatment in coordination with a psychiatrist.
Although the psychiatrist would prescribe the antipsychotic in this case, some important items are presented here. First, the history and collaborative information would be helpful to ensure the diagnosis of schizophrenia is correct. The current mental status exam and the remote last cocaine usage make a cocaine-induced psychotic disorder unlikely as the sole diagnosis. But in patients with more recent cocaine exposure, this diagnosis must be considered.
In regards to treatment, "typical" antipsychotics or "older" neuroleptics have a higher propensity for hyperprolactinemia, tardive dyskinesia, and extrapyramidal side effects (EPS) including dystonias (involuntary muscle contractions), akithisia (restlessness, fidgeting) and parkinsonism. In patients with HIV/AIDS, this rate may be increased three-fold, reportedly due to the predilection of the HIV virus for the basal ganglia and associated areas of the brain. Furthermore, medications to minimize EPS symptoms such as diphenhydramine (Benadryl) and benztropine (Cogentin) often worsen cognitive functioning due to the anticholinergic effects of these drugs. Newer, or "atypical", antipsychotic medications are considered treatments of choice for schizophrenia but may carry increased risks of the metabolic syndrome with hyperlipidemia and/or non-insulin dependent diabetes mellitus (NIDDM). In particular, studies have most closely linked olanzapine (Zyprexa) to these problems, although all agents in this class carry the warning in their package insert. The NIDDM is not directly associated with the increase in patient weight with the initiation of the drug. One of the six atypical agents (Clozaril) can cause agranulocytosis and is not usually considered in HIV patients. Two of the remaining five agents (Geodon and Abilify) are CYP p450 3A4 substrates, which may create challenges to future antiretroviral management, particularly ritonavir-containing regimens. Risperidone (Risperdal) or queitapine (Seroquel) might be the best choices in this patient. Risperidone is now available in a depot injection form (Risperdal Consta) that may be administered every two weeks in non-adhering patients. Due to the timing of antiretroviral treatment, potential drug interactions, and the need for metabolic monitoring (glucose/lipid), ongoing coordination between the HIV provider and the psychiatrist will continue to provide the best possible outcome for this patient.
Jeffrey Watts, M.D., is the Psychiatric Medical Director at CORE Center. He is on the Speaker's Bureaus for BMS Virology and Abbott Virology.