incorporating HIV testing in the routine battery of prenatal tests (CDC, 2003b).

Care of the HIV-infected individual requires specific attention to the interplay of co-occurring diseases of substance abuse and mental illness (Douaihy et al., 2003a, 2003b; Bruce and Altice, 2003; Bing et al., 2001; Altice and Friedland, 1998; CSAT, 1995, 2000). Several reasons support the need to provide care delivery strategies that are comprehensive and that meet the standards of care for these three diseases. First, adherence to antiretroviral treatment may be undermined by co-occurring substance abuse and mental illness and could lead to the development of drug resistance. Second, the clinical management of HIV-infected individuals must take into account the impact of substance abuse and mental illness and their treatment on the expression of symptoms, the development of drug interactions, progression of HIV disease, the utilization of care services, and high-risk HIV behaviors (see Box 3-4).

Drug treatment adherence. As noted in Chapter 2, adherence to antiretroviral therapy is critical for therapeutic effectiveness (Harrigan et al., 2003; Garcia de Olalla et al., 2002; Bangsberg et al., 2001; McNabb et al., 2001; Paterson et al., 2000). However, an individual’s ability to adhere to a treatment regimen may be related to co-occurring substance abuse and mental illness (Ferrando et al., 1996; Sternhell and Corr, 2002; Starace et al., 2002). A longitudinal study of the effects of continued drug use on the treatment of HIV infection in patients who attend an urbanized HIV clinic (Lucas et al., 2002) found that switching from non-use to substance abuse was strongly associated with worsening antiretroviral therapy use and adherence, less frequent HIV-1 RNA suppression, and blunted CD4 cell increases. The researchers also found that switching from substance abuse to non-use was strongly associated with improvements in antiretroviral therapy use and adherence, and HIV-1 treatment.

Tucker and colleagues (2003) analyzed data from the HCSUS study to investigate the association of antiretroviral medication nonadherence with specific types of psychiatric disorders and drug use, and with varying level of alcohol use. The researchers found that patients with depression, generalized anxiety disorder, or panic disorder were more likely to be nonadherent than those without a psychiatric disorder. Nonadherence was also associated with use of cocaine, marijuana, amphetamines, or sedatives in the previous months. Moderate and heavy alcohol use compared with no alcohol use was also found to be associated with nonadherence (Tucker et al., 2003). Researchers in Canada (Palepu et al., 2003) made similar find-