During 12 years of follow-up (1996–2007), we observed a higher mortality risk for HIV-infected patients diagnosed with both psychiatric and SU disorders in comparison to patients with neither diagnosis. However, we observed that psychiatric and SU treatment, in general, reduced mortality risk in single and dual diagnosed patients, and remained statistically significant even after adjustment for age, race, immune status, HIV viral load, antiretroviral therapy use, and other potential confounders. Accessing psychiatric treatment reduced mortality risk among dual diagnosed patients who were treated or not treated for SU disorder.
Previous studies of individuals with HIV infection have found that those with psychiatric disorders are at elevated risk for poor medication adherence and clinical outcomes.20, 38
There is substantial evidence that depression, stressful life events and trauma affect HIV disease progression and mortality.15,39
This effect has been found even controlling for medication adherence, in a study that showed that HAART adherent patients with depressive symptoms were 5.90 times (CI
2.55–13.68) more likely to die than adherent patients with no depressive symptoms.41
Depressive symptoms independently predicted mortality among women with HIV,18
and also in a separate study of men.17
Similarly, in multivariate analyses controlling for clinical characteristics and treatment, women with chronic depressive symptoms were 2 times more likely to die than women with limited or no depressive symptoms (relative risk [RR], 2.0; 95% CI 1.0–3.8).16
Among women with CD4 cell counts of less than 200
10(6)/L, HIV-related mortality rates were 54% for those with chronic depressive symptoms (RR, 4.3; 95% CI, 1.6–11.6) and 48% for those with intermittent depressive symptoms (RR, 3.5; 95% CI, 1.1–10.5) compared with 21% for those with limited or no depressive symptoms. Chronic depressive symptoms were also associated with significantly greater decline in CD4 cell counts after controlling for other variables.16
These mechanisms could help to explain the greater risk of mortality observed in our sample.
Our findings strongly highlight the importance of access to psychiatric and SU disorder treatment for this population. It was estimated that during a 6-month period, 61.4% of 231,400 adults in the United States receiving treatment for HIV/AIDS used psychiatric or SU disorder treatment services.42
A significant number of HIV-infected patients report accessing psychiatric services.25
Such visits are associated with decreased risk of discontinuing HAART.25
Burnam et al.42
found that those with less severe HIV-related illness were less likely to access psychiatric or SU disorder treatment. One study found that engagement in SU disorder treatment was not associated with a decrease in hospital use by HIV-infected individuals with a history of alcohol problems.43
Improvement in depression was associated with increase in HAART adherence among injection drug users.26
Study strengths and limitations
A limitation of our study may have been the differences in timing of the psychiatric diagnosis and/or SU diagnosis. Some patients in our sample may have received their psychiatric diagnosis shortly after the onset of symptoms or in the initial phase of substance dependence or abuse, while other patients may have been diagnosed at a more advanced stage. Some patients may have met the criteria for a psychiatric or SU diagnosis without receiving one. In addition, some study subjects may have received psychiatric care or informal SU disorder services (e.g., Alcoholics Anonymous) or self-pay services outside of the KPNC health plan, and our study does not have information about those services. We also could not control for level of comorbidity (e.g., Charlson index) for other (not HIV-related) diseases and conditions at baseline, because many patients had insufficient health plan membership time prior to study entry.
This study examined mortality among HIV-infected patients with private health insurance who received medical care in an integrated health plan, who had full access to psychiatric and SU disorder services, and who had received diagnoses of psychiatric disorder and substance dependence or abuse by a clinician. Our study was conducted among one of the largest clinical cohorts of HIV-infected patients in the United States. Given the current movement towards healthcare reform, it is important to investigate survival patterns of HIV-infected individuals within a health plan with characteristics similar to those plans that may result from health reform.
In summary, higher mortality occurred among HIV-infected patients diagnosed with psychiatric and SU disorders for whom access to medical services and ability to pay for care are not significant factors. In this analysis we did not observe significant differences in cause of death by psychiatric disorder status. The occurrence of higher mortality among these dual diagnosed patients receiving HIV/AIDS care may indicate that even when psychiatric treatment and SU treatment is available but not accessed, HIV-infected patients with psychiatric and co-occurring substance problems remain vulnerable to less than optimal health outcomes. Our study findings suggest that screening for psychiatric disorder and for SU problems at the initiation of HIV/AIDS treatment (and throughout the course of HIV/AIDS patient care) and providing psychiatric and SU disorder treatment may prove beneficial and extend life for these heavily burdened patients.