Psychiatric comorbidity in depressed HIV-infected individuals: common and clinically consequential

Abstract

Objective

To report on the prevalence of psychiatric comorbidity and its association with illness severity in depressed HIV patients.

Methods

As part of a multi-site randomized controlled trial of depression treatment for HIV patients, 304 participants meeting criteria for current Major Depressive Disorder (MDD) were assessed for other mood, anxiety and substance use disorders with the Mini-International Neuropsychiatric Interview, a structured psychiatric diagnostic interview. We also assessed baseline adherence, risk, and health measures.

Results

Complicated depressive illness was common. Only 18% of participants experienced MDD with no comorbid psychiatric diagnoses; 49% had comorbid dysthymia, 62% had ≥ 1 comorbid anxiety disorder, and 28% had a comorbid substance use disorder. Self-reported antiretroviral adherence did not differ by the presence of psychiatric comorbidity. However, psychiatric comorbidity was associated with worse physical health and functioning: compared to those with MDD alone, individuals with ≥ 1 comorbidity reported more HIV symptoms (5.1 vs. 4.1, P= .01), and worse mental health-related quality of life on the SF-12 (29 vs. 35, P< .01).

Conclusion

For HIV patients with MDD, chronic depression and psychiatric comorbidity are strikingly common, and this complexity is associated with greater HIV disease severity and worse quality of life. Appreciating this comorbidity can help clinicians better target those at risk of harder-to-treat HIV disease, and underscores the challenge of treating depression in this population.

Introduction

Twenty to thirty percent of HIV-infected patients have depression or depressive symptoms, and these states have been associated with decreased access to antiretroviral therapy (ART) [1], [2], [3], [4], decreased likelihood of initiation of and retention in HIV care [5], [6], poor antiretroviral adherence [7], worse psychiatric outcomes [8], and worse medical outcomes, including lower likelihood of virologic suppression, faster HIV disease progression, and higher mortality rates [9], [10]. HIV care providers and researchers have argued that increased access to effective depression treatment would lead to substantial improvements in HIV clinical outcomes for affected individuals [8], [11], although current evidence is somewhat mixed on this point [12], [13], [14], [15], [16], [17], [18].

A key consideration in determining whether improved depression care can lead to improved HIV outcomes in HIV-infected individuals with Major Depressive Disorder (MDD) is how comorbid psychiatric illness might confound this relationship. Indeed, few studies have thoroughly considered the role of psychiatric comorbidity, i.e., the co-occurrence of other psychiatric disorders with depression, in explaining the observed association between depressive symptoms and adverse HIV outcomes. For psychiatric illness in general, and MDD in particular, having more than one concurrent psychiatric diagnosis is common [19]. This psychiatric comorbidity is strongly related to both greater psychiatric severity [19] and worse psychiatric outcomes (including greater fatigue and functional impairment [20] and higher rates of suicide attempts [21]). In addition, psychiatric comorbidity is associated with greater medical symptomatology [22] and worse medical outcomes [23]. Finally, MDD that is comorbid with dysthymic, anxiety, or substance use disorders is likely to be more difficult to treat, which might complicate efforts to reduce depressive severity and improve HIV outcomes through depression treatment interventions.

However, documentation of psychiatric comorbidity in HIV patients receiving treatment in limited. Indeed, while studies have reported on the heavy burden of psychiatric illness in HIV-infected populations [24], [25], no prior study has specified psychiatric comorbidity in a sample of HIV-infected patients with a confirmed diagnosis of MDD, nor whether this comorbidity is associated with greater illness severity. In this paper, our team assesses the prevalence and correlates of psychiatric comorbidity among a population of HIV-infected patients with confirmed MDD who enrolled in a depression treatment study. We examine the extent to which depression treatment interventions for HIV-infected individuals needs to consider psychiatric comorbidity for maximal reach and effectiveness. Accordingly, our goals for this paper are 1) to describe the prevalence of comorbid psychiatric disorders in persons with MDD enrolling in a depression treatment study in a representative sample of HIV outpatients, and 2) to identify sociodemographic and clinical/behavioral features associated with the number and type of concurrent psychiatric conditions.