HIV/AIDS

What Is HAART?

The availability of HAART since 1996 has had a dramatic effect on the face of HIV/AIDS. HAART is a customized combination of different classes of medications that a physician prescribes based on such factors as the patient's viral load, CD4⁺ lymphocyte count, and clinical symptoms. CD4⁺ lymphocytes are white blood cells that HIV infects and kills, leading to a weakened immune system and AIDS. Though not a cure, HAART controls viral load, helping to delay the onset of symptoms and achieve prolonged survival in people diagnosed with HIV/AIDS.⁵

With HAART, the medical consequences associated with HIV/AIDS have changed. New diagnoses of HIV-associated infections and some neurological complications, such as HIV dementia, have decreased since its introduction.^5,6 However, other neurological problems, such as peripheral nerve damage, have increased with the use of this therapy. HAART is also reported to be associated with increased lipid levels (including cholesterol) in the blood, abnormal glucose metabolism, and other clinical complications such as heart disease.

Potential interactions between HAART and medications used to treat drug addiction may decrease the effectiveness of either or both treatments. For instance, when methadone, a treatment for heroin and other opioid addictions, is administered with certain antiretroviral medications that are components of HAART therapy, the concentration of methadone in the blood is significantly decreased,⁹ potentially compromising its effectiveness. Research is under way to determine if buprenorphine, a newer medication for the treatment of opioid addictions, has similar liabilities.

One of the challenges for patients treated with HAART is adhering to the medication routine needed for maximum benefit from this therapy. Adherence can be particularly problematic for drug abusers with chaotic lifestyles, which can interfere with their ability to follow prescribed regimens. In addition, because HAART reduces viral load, some patients mistakenly believe that they do not need to adhere to the treatment regimen or that reduced viral load means elimination of the risk of transmitting HIV.^10,11,12 This belief can, in turn, lead to complacency about risk behaviors and resumption of unsafe sex and injection practices.¹³ NIDA-supported research has helped to improve HIV outcomes among injecting drug users (IDUs) and has advanced new discoveries and approaches for treating medical consequences resulting from living longer with the disease.

Which Populations Are Most Affected?

While all groups are affected by HIV/AIDS, not all are affected equally. The first populations to be affected by AIDS were primarily men who have sex with men (MSM) and IDUs. In fact, injection drug use has been associated directly or indirectly (e.g., through sex with IDUs, mother-child transmission) with more than one-third of AIDS cases in the United States. IDUs continue to be at increased risk of HIV and other infections associated with drug abuse, including the hepatitis C virus (HCV), hepatitis B virus (HBV), endocarditis, skin infections, and abscesses. Over the past several years, however, the proportion of AIDS cases attributable to injection drug use has declined significantly, while AIDS cases attributable to heterosexual transmission have increased. From 1999 through 2003, the annual number of AIDS diagnoses attributable to heterosexual contact increased 28 percent among women and 20 percent among men. In 2003, MSM and those exposed through heterosexual contact together accounted for 73 percent of cases, with MSM accounting for nearly 42 percent of the total cases.¹⁴

African-Americans experience striking disparities in HIV-infection rates compared with other populations, and they are at particularly high risk for developing AIDS. To illustrate, while African-Americans make up just 12 percent of the U.S. population, they accounted for half of the total AIDS cases diagnosed in 2003. Moreover, African-American females accounted for 69 percent of the female HIV/AIDS diagnoses from 2000 through 2003 -- 19 times the rate for White females and 5 times the rate for Hispanic females.¹⁵ And although African-Americans ages 13-19 represent only 15 percent of U.S. teenagers, they accounted for 66 percent of new AIDS cases reported among teens in 2003.¹⁶

Young people (ages 13 to 24) are also at risk for HIV/AIDS, with minority youth at particularly high risk. According to the Centers for Disease Control and Prevention (CDC), an estimated 38,490 young people in the United States had been diagnosed with AIDS, approximately 4 percent of the cumulative AIDS cases through 2003. Moreover, between 1999 and 2003, the proportion of young people diagnosed with AIDS increased from 3.9 percent to 4.7 percent. Particular HIV risk behaviors of this group, including sexual experimentation and drug abuse, are often influenced by strong peer group relationships and diminished parental involvement that can occur during adolescence.

Compounding this adolescent vulnerability today is the notion of "generational forgetting," which is a diminished view of the dangers of HIV/AIDS among certain members of today's generations. Studies show that today's youth may be more likely to hold this view than older Americans who witnessed a higher AIDS mortality rate associated with the rapid progression from HIV to AIDS early in the epidemic. In addition, one study comparing youth living with HIV before and after the era of HAART found that post-HAART youth were more likely to engage in unprotected sex and substance abuse; however, whether this outcome is a direct result of the availability of HAART is not known.¹⁹