Psychiatric Times 
November 2005
Vol. XXII
Issue 13
Patients with HIV infection are at risk of developing psychiatric symptoms and disorders similar to those seen in the general population. Even before infection, people at risk for HIV may come from certain populations--such as injection-drug users and others with substance abuse or dependence--in whom there is a higher than average risk for psychiatric illness (Pillard, 1988; Rounsaville et al., 1982). Symptoms of anxiety and depression may be related to apprehension about disease progression and death and sadness from the loss of health, friends and income (Forstein, 1984; Nichols, 1985; Ostrow, 1987).
Several studies have found a substantial risk for DSM-III major depression and adjustment disorders with anxious or depressed mood, which may occur during asymptomatic infection (Dilley et al., 1985; Holland and Tross, 1985). In addition, patients living with an underlying mental illness--especially severe and persistent mental or mood disorders--are at a disproportionately increased risk of developing infection with HIV due to sexual and substance use behaviors (Carey et al., 2004).
HIV and the Brain
Shortly after the initial HIV infection, the virus enters the central nervous system and may cause meningitis or encephalitis. Other serious CNS complications tend to occur late in the course of disease, when immune function has significantly declined, though studies have reported conflicting results as to the predictive value of CD4 counts in assessing cognitive and motor performance (Bornstein et al., 1991; Goethe et al., 1989; Koralnik et al., 1990; McArthur et al., 1989; Miller et al., 1990; Saykin et al., 1988). Viral load is more closely associated with the degree of cognitive impairment. Patients with serum viral loads ≥30,000 copies/mL are 8.5 times more likely to develop dementia compared to patients with viral loads <3,000 copies/mL (Childs et al., 1999). In another study, a cerebrospinal fluid viral load >200 copies/mL was predictive of progression to neuropsychological impairment (Ellis et al., 2002).
HIV-Associated Dementia
Patients infected with HIV are at risk of developing dementia as a direct result of viral infection. This syndrome has been referred to by various names: HIV-associated dementia complex (HAD) (Working Group of the American Academy of Neurology AIDS Task Force, 1991), HIV encephalopathy, subacute encephalitis (Snider et al., 1983), AIDS encephalopathy and AIDS-dementia complex (Navia et al., 1986b). HIV-associated dementia is defined as acquired cognitive abnormalities in two or more domains and is associated with functional impairment and acquired motor or behavioral abnormalities, in the absence of another etiology (Table 1).
