from suicide, inadequately treated comorbid medical problems like diabetes (Dixon et al., 2000; Sullivan et al., 1999), or from physiological interrelationships between MI and comorbid medical conditions (see later section on depression). On a separate disability measure that includes both mortality and disability,4 depression ranks directly behind HIV—yet both rank within the top ten (WHO, 2001). The loss of productivity to the United States economy from MI totals about $63 billion annually (DHHS, 1999). There are a range of effective treatments for most mental disorders—medications, psychotherapies, and other services and supports—but 50 percent of those with mental illness do not receive any treatment because of barriers to access (DHHS, 1999).
About 5–9 percent of United States adults and children have more severe forms of mental illness (Kessler et al., 2001; NHSDA, 2002; DHHS, 1999). For adults, the commonly used term is “serious mental illness.” Stemming from federal regulations, the term refers to a diagnosable mental disorder that impairs performance at work, home, or other area of social functioning. The analogous regulatory term for children is “serious emotional disturbance.” The disorders subsumed by either of these terms are typically severe depression, bipolar disorder, and schizophrenia. Their onset typically occurs in later adolescence or early twenties. Ninety percent of adults with serious mental illness are unemployed (DHHS, 1999).
This appendix focuses on the full range of mental disorders, from milder depression to serious mental illness, because most disorders are overrepresented in the HIV population, and the general barriers to MI or HIV treatment do not vary by mental disorder.
People with MI are at higher risk for HIV than those without MI (Cournos and McKinnon, 1997; Stoskopf et al., 2001). The comorbidity of MI-HIV has been largely studied in two different ways—in samples either receiving mental health care, or in samples receiving HIV care. Neither sample type is representative of the population with MI-HIV comorbidity, partly because so many are not in treatment. Among people with serious mental illness (SMI), the seroprevalence of HIV ranges from 4 to 23 percent, with an average of about 7 percent (Carey et al., 1995; Cournos and McKinnon, 1997). That average is much higher than the rate of HIV in the general United States population (0.3–0.5 percent). Among people in HIV care, the prevalence of MI is at least 50 percent (Bing et al., 2001). This rate