Less than half of people living with HIV in the United States are being retained in ongoing medical care, according to a new analysis by U.S. Centers for Disease Control and Prevention (CDC) investigators published online ahead of print by the Journal of Acquired Immune Deficiency Syndromes. The sobering statistics, which include the finding that only two thirds of people testing positive for HIV are being successfully linked to medical care within a year of their diagnosis, help explain those of another recent CDC analysis indicating that only 28 percent of U.S. residents living with HIV have undetectable viral loads.

It is well established that antiretroviral (ARV) therapy substantially improves disease-free survival rates among people living with HIV and shows potential as a method to reduce HIV transmission rates. Yet these positive health outcomes depend heavily on consistent engagement of people living with HIV in medical care, which is an integral component of the National HIV/AIDS Strategy.

It is also well known that an individual’s health outcomes are associated with that person’s being linked to and retained in medical care. In at least two studies, missed clinic appointments were independently associated with a decreased likelihood of receiving ARV therapy and poorer rates of viral load suppression after one year of commencing treatment.

Connections between entry and retention in medical care and ongoing transmission of the virus have also been documented. In one 2008 study, for example, people living with HIV presenting for medical care at least three times in a one year period were less likely to engage in risky sexual behavior compared with those with fewer visits.

More recently, analyses conducted by researchers in British Columbia and Washington, DC, have suggested a correlation between ARV therapy–associated community viral load reductions and the rate of new HIV infections. These findings are further realized with the completion of a prospective study involving 1,763 HIV-serodiscordant couples, which documented a relative reduction of 96 percent in the number of HIV transmissions resulting from the early initiation of ARV treatment, as compared with delayed therapy.

But for these benefits to be realized on a national and global scale, maximizing entry and retention in medical care needs to be a priority, H. Irene Hall, PhD, MPH, and her colleagues of the CDC note in their new JAIDS report.

Yet a large swath of U.S. residents living with HIV is not receiving appropriate medical care. Of the 1.1 million people estimated to be HIV positive in the United States, 21 percent are unaware of their serostatus (CDC, 2008). And according to a 2010 analysis reviewed by Hall’s group, only 69 percent of those aware of their positive serostatus have entered medical care, whereas 59 percent been retained in care.

To further explore the issue of entry and retention in care, Hall and her colleagues used data from 13 areas—Delaware, the District of Columbia, Iowa, Indiana, Kentucky, Missouri, Nebraska, New York State (excluding New York City), North Dakota, San Francisco, South Carolina, West Virginia and Wyoming—reporting relevant HIV-related tests to the CDC. 

Individuals were considered to have entered medical care if they had at least two HIV-related tests, notably CD4 cell counts or viral load testing, at least three months apart within 12 months after being diagnosed with HIV. Similarly, individuals were considered to have been retained in medical care if they had at least two HIV-related tests at least three months apart within the past year.

Among 100,375 people living with HIV included in the analysis, 45 percent met the criteria for being successfully retained in medical care. According to Hall and her colleagues, a higher percentage of whites was retained in care (50 percent) compared with blacks (41 percent) or Latinos (40 percent). And compared with heterosexual women, 50 percent of whom were retained in medical care, fewer men who have sex with men (48 percent), males infected with HIV though heterosexual sex (45 percent), and male and female injection-drug users (37 and 43 percent, respectively) were being adequately retained in medical care.

About two thirds, or 64 percent, of those who tested positive entered into clinical care within 12 months of their HIV diagnosis. Nearly 75 percent of whites testing positive for HIV met the criteria for having successfully entered care within one year of their diagnosis, compared with 54 percent of blacks and 69 percent of Latinos. Rates of establishment in care following diagnosis were also lower among younger (13 to 24 years old) and older (65 and older), compared with those between 25 and 64 years old. And similar to rates of retention in care, women who contracted HIV through heterosexual sex were more likely to have successfully entered into care, compared with the other risk groups among females and males.

Though the CDC’s data analysis was not able to explore reasons for the low clinical care entry and retention rates, a myriad of possible factors have been cited. Demographic characteristics include no or public insurance, lower socioeconomic status, rural residence and no usual source of medical care. Disease severity, notably less advanced HIV disease and fewer non-HIV illnesses, has also been found to be a predictor of poor medical care adherence, along with a variety of other characteristics, including substance use, low readiness to enter care and less social support. Possible health care system failures include poor utilization of social services and other shortcomings in addressing unmet patient needs.

A key limitation of the study was the size of its population. By including only 13 areas within the United States, Hall and her colleagues note, the researchers were only able to assess the entry and retention statuses of 12 percent of all people living with HIV in the country. “As additional areas improve laboratory reporting to CDC,” the authors comment, “future estimates of care utilization will be more representative.”

Still, the conclusion is disappointing. “In summary,” Hall’s team notes, “we found a large proportion of people with HIV are not in continuous care and such care is lower among blacks/African Americans, Hispanics and specific risk groups such as injection-drug users compared with their counterparts.” They add: “Assuring [that people living with HIV] receive HIV care benefits the individual and can reduce transmission risk by reducing infectiousness among those with suppressed viremia and by reducing behavioral risk through prevention services in the health care setting, including risk screening, counseling and condom distribution. Implementation of effective linkage and care retention interventions is needed to raise the percentage of [people living with HIV] in continuous HIV care.”