Rates at which HIV-positive people in the United States entered care, stayed in care, started antiretroviral therapy, and reached a viral load below 200 copies differed by sex, age, race, and year in a study of more than 18,000 people across eight states and Washington, D.C.1 Once in care, women remained in care more often than men, but men entered care more often than women in two of the three study years. Older people stayed in care, filled antiretroviral prescriptions, and reached a low viral load more often than younger people. And Latinos stayed in care significantly more often than whites or blacks.
To understand trends in HIV care, researchers study how often people who test positive for HIV enter care, stay in care, start antiretroviral therapy, and reach an undetectable viral load. But much of this research has not recorded changes in these trends over time or determined whether trends differ between men and women, between older people and younger people, and between blacks, whites, Hispanics, and Asians.
Also, studies use different methods to determine what proportion of HIV-positive people fall into each stage (enter care, stay in care, take antiretrovirals, reach a low viral load, Figure 1). Some studies use a dependent method in which a person has to meet the definition for one stage to be considered in the next stage (Figure 1). Other studies use an independent method, which considers each stage independently. For example, a person might not meet the study definition for staying in care yet still start antiretroviral therapy and reach a low viral load.
Researchers with the Kaiser Permanente healthcare system conducted this analysis using both dependent and independent methods to determine how many HIV-positive Kaiser patients entered care, stayed in care, started antiretrovirals, and reached a viral load below 200 copies over the course of 3 years.
How the Study Worked
The study involved HIV-positive people at least 13 years old receiving care with Kaiser Permanente in one of eight states or Washington, D.C. in 2010, 2011, or 2012. Researchers checked Kaiser's electronic medical records for each study participant to determine age, sex, and race and whether they met definitions for the four stages of care (Figure 1):
- Linked to care: (1) For new patients, one medical visit or CD4 count within 90 days of testing positive for HIV. (2) For established patients, one or more medical visits each year.
- Stayed in care: Two or more medical visits at least 60 days apart in each year.
- Filled antiretroviral prescription: One 90-day prescription fill or three 30-day prescription fills.
- Viral load control: Viral load below 200 copies when last measured in each year.
Researchers used both the dependent method and the independent method (Figure 1) to determine proportions of HIV-positive people in each of the four stages of care in each study year: 2010, 2011, and 2012. They used only the independent method to calculate proportions of people in each of the four stages according to sex (male or female), age group (13 to 34, 35 to 54, or 55 or older), and race or ethnic background (white, black, Latino, Asian or Pacific Islander, or other or unknown). The researchers used a standard statistical method to see whether differences between groups were statistically significant (meaning the difference cannot be explained by chance).
What the Study Found
The analysis focused on 16,835 HIV-positive people in 2010. That number rose to 17,738 in 2011 and to 18,270 in 2012. Overall 87% of these people were men. About 10% were younger than 35, about 60% were 35 to 54, and about 30% were 55 or older. While 46% of study participants were white, 24% were black, 18% Latino, and 5% Asian or Pacific Islander. About 95% of people who took antiretroviral therapy took their drugs on time, as their clinician prescribed.
With both the dependent method and the independent method (Figure 1), the same proportions of people were linked to care (about 97% in all three study years) and about the same proportions stayed in care (about 80% in all study years). But the independent method figured much higher proportions who filled antiretroviral prescriptions (87% versus 71% with the dependent method in 2012) and much higher proportions who reached a viral load below 200 copies (86% versus 66% with the dependent method in 2012). For all analyses comparing care rates by sex, age, and race or ethnic background, researchers used only the independent method.
Using the independent method, the Kaiser researchers determined that 96% of people who tested positive for HIV started care in 2012, 80% stayed in care, 87% filled their antiretroviral prescription, and 86% reached a viral load below 200 copies. Staying in care, filling antiretroviral prescriptions, and reaching a viral load under 200 copies all improved significantly from 2010 to 2012.
In 2010 and 2011 a significantly higher proportion of men than women entered care, but in 2012 a slightly higher proportion of women than men entered care. Once in care, women stayed in care at a significantly higher rate than men in all 3 study years. Despite this higher rate of staying in care, women filled antiretroviral prescriptions significantly less often than men in all 3 study years. And a lower proportion of women than men reached a viral load below 200 copies in all 3 study years. The gap between men and women in antiretroviral prescription filling and reaching a sub-200-copy viral load narrowed substantially from 2010 to 2012 (from 9.6% to 6.5% for prescription filling and from 10.2% to 5.0% for viral load).
Rates of entry to care did not differ much between the three age groups (under 35, 35 to 54, and 55 or older) in any of the 3 study years. But the oldest age group had significantly higher proportions staying in care and reaching a viral load below 200 copies than the younger age groups in each of the 3 years studied. And the oldest age group had a significantly higher proportion filling antiretroviral prescriptions than the youngest age group in all 3 years. Each of the three age groups improved over the 3-year period in filling antiretroviral prescriptions and in reaching a viral load below 200 copies (Figure 2).
Similar proportions of the four racial groups entered care after their HIV diagnosis (Table 1). Entering care improved from 2010 through 2012 in whites, Latinos, and Asians, but it dropped slightly in blacks over the 3 study years. Higher proportions of Latinos than whites or blacks stayed in care through the study period; whites and blacks did not differ from each other in proportions staying in care.
Higher proportions of whites than the other three racial groups filled antiretroviral prescriptions and reached a viral load below 200 copies in all study years (Table 1). Rates at which people filled antiretroviral prescriptions and reached a viral load below 200 copies improved from 2010 through 2012 in all four racial groups.
|Table 1. Rates of Care in Four U.S. Racial or Ethnic From 2010 Through 2012|
| ||Entered Care||Stayed in Care||Filled ART Rx||Viral Load Below 200 Copies|
|Whites||No difference from other groups||Worse than Latinos, similar to blacks||Better than all other groups||Better than all other groups|
|Blacks||No difference from other groups||Worse than Latinos, similar to whites||Worse than whites||Worse than whites|
|Latinos||No difference from other groups||Better than all other groups||Worse than whites||Worse than whites|
|Asians/Pacific Islanders||No difference from other groups||Worse than Latinos||Worse than whites||Worse than whites|
ART Rx, antiretroviral therapy prescription.
What the Results Mean for You
Today's antiretroviral combinations are stronger and much easier to take than the combinations used 10 to 20 years ago. As a result, most people with HIV infection can now lead long and productive lives. To enjoy the benefits of antiretroviral therapy, people with HIV have to do four things (Figure 1): They have to start care for HIV infection, they have to stay in care, they have to start antiretroviral therapy, and they have to take their antiretrovirals steadily to reach an undetectable viral load.
This 3-year study of more than 18,000 HIV-positive people in eight U.S. states and Washington, D.C. made many important findings about these stages of HIV care. Overall, more than 4 in 5 people who tested positive for HIV started HIV care, stayed in care, started antiretroviral therapy and filled their prescriptions, and reached a viral load below 200 copies. Among people who started antiretroviral therapy, about 95% took their antiretrovirals on time. All these findings show that most people in this eight-state healthcare plan were taking all the required steps to keep their HIV infection under control.
But rates at which people took these steps differed by sex (men versus women), age (under 35, 35 to 54, 55 or older), and race or ethnic background (white, black, Latino, Asian or Pacific Islander). Among the many differences, several stand out:
- Men started HIV care more often than women, but once in care women stayed in care more than men.
- Despite staying in care more often than men, women took antiretroviral therapy less often than men and -- as a result -- reached a viral load below 200 copies less often than men.
- The oldest age group stayed in care, took antiretroviral therapy, and reached a viral load below 200 copies more often than the younger age groups.
- Higher proportions of Latinos than whites or blacks stayed in care for HIV infection.
- Higher proportions of whites than the other three racial groups filled antiretroviral prescriptions and reached a viral load below 200 copies.
The researchers who conducted this study stress that HIV providers should take steps to determine which groups of their patients do poorly at each of these stages of care. Then providers can address problems that may prevent each patient group from getting the care they need to reach an undetectable viral load. At the same time, each individual with HIV infection has a personal responsibility to start care for their infection and to stay in care. The United States and many other countries now recommend that everyone with HIV should start antiretroviral therapy. And everyone who starts therapy should take their pills regularly and aim to reach an undetectable viral load.
Anyone with HIV may face obstacles in meeting all the requirements of care. This study and others found that younger people may have a particularly hard time staying in care, taking antiretroviral therapy regularly, and reaching an undetectable viral load. Talk to your HIV provider about problems you face in your care. Your provider may be able to solve some of these problems (for example, by finding an antiretroviral combination that's easier for you to take). Or your provider may put you in touch with a case manager or other health worker who can address other problems (like getting health insurance or using government insurance programs like Medicaid and Medicare).
The good news from this study is that rates of staying in care, taking antiretroviral therapy, and reaching a low viral load generally improved from 2010 through 2012 in all groups studied -- men and women, young and old, and all racial or ethnic groups. This improvement partly reflects efforts made by the Kaiser Permanente healthcare group to identify problems in steady HIV care and to find solutions for those problems. The improvement may also reflect a growing awareness among people with HIV that they will feel better and live longer if they get treatment for their infection and take their antiretrovirals regularly.
- Horberg MA, Hurley LB, Klein DB, et al. The HIV care cascade measured over time and by age, sex, and race in a large national integrated care system. AIDS Patient Care STDs. 2015;29:582-590.