USA Today: 5 Facts about HIV on World AIDS Day.

Red Ribbon for AIDS Awareness

Today is not just Cyber Monday, today is also World AIDS day. A day for awareness of the continuing threat the disease poses to people all around the world. Today's article, from USA Today, is one of many that has come out today to help remind and educate people about HIV and AIDS.

The five facts today's article shares are that 34 million people world wide are HIV positive--with 1.2 million of those living in the US, 70% of new HIV cases occur in Sub-Saharan Africa, the rate of new infections in the US is down to about 50,000 per year from a height of 130,000 per year in the 1980s, advances in anti-retroviral treatments means that many people can live relatively normal lives after an HIV diagnoses even though there is still no cure, and though the death rate due to AIDS has dropped overall teens are still dying of AIDS at the same rate they were in 2005.

For my contribution to spreading awareness and understanding about AIDS, I would like to look into that last fact in more detail. What has research shown to be the cause of the consistent high death rate of HIV+ teens in spite of the dropping death rate overall?

To begin to better understand what is going on we will be looking at a research article published last week in the CDC's Morbidity and Mortality Weekly Report. While the work presented in this publication is done by known researchers of epidemiology (the study of disease spread) or medicine and public health, the work is considered preliminary and has not been subject to peer review. In many ways this makes reading this report much like attending a scientific conference; the information is presented in good faith, but occasionally further investigation may show the initial findings to be inaccurate. With that caveat out of the way, let's look at the research itself.

What did the authors of the CDC's Morbidity and Mortality Weekly Report article find out about the high death rate of HIV+ teens?

For this study researchers looked at a large sample of medical records for patients of HIV/AIDS treatment centers in seven African countries (Côte d'Ivoire, Nigeria, Swaziland, Mozambique, Zambia, Uganda, and Tanzania). They selected patients that began receiving treatment any time between 2004 and six months prior to the beginning of the experiment (2012). They collected information about the patients' age, sex, marital and employment status, and pregnancy while focusing on two primary measures of treatment failure: death and treatment-program drop out. Drop out was defined as a patient having no visits to the clinic in the last 90 days for an appointment, laboratory work, or a prescription refill.

For statistical analysis, researchers grouped the patients into three age categories: 15-24, 25-49, and 50+. They then compared these three groups. 9% of the total patient sample was in the youngest age group, the vast majority were in the middle age group. In all seven countries the young group was almost all female: 81-92% depending on country. The middle group was also mostly female: 60-68%. The oldest group, in contrast, was roughly evenly distributed between males and females.

In five of the six countries that provided pregnancy data, the pregnancy rate was higher in the youngest group (16-32%) than in the middle group (9-14%), in the sixth the pregnancy rate was the same. The opposite pattern was seen for marriage and employment. The marriage rate was higher in the middle group (43-60%) and oldest (43-65%) than in the youngest group (27-46%). Employment was only tracked in four countries and likely confounded by age and sex, but the employment rate was 14-47% for the youngest group compared to 49-63% for the middle group and 53-70% for the oldest.

To look at the differences in clinical outcome (rate of death or drop-out) all groups were compared to the oldest group from the same country.

In three of the seven countries researchers found a statistically significant difference in the rate of dropout between the youngest and oldest patients; in all cases the younger patients were more likely to drop out. The adjusted hazard ratio of dropping out was >1 for the youngest patients in all seven countries (i.e. even in the counties where the difference was not statistically significant, young patients dropped out more often than old patients).

In two of the seven countries there was a statistically significant difference in death rate. In both those countries, Swaziland and Uganda, the adjusted hazard ratio for the youngest patients was less than one: in those countries young patients died less often. In Mozambique, Zambia, and Tanzania the youngest patients were more likely to die (hazard ratio >1), but the difference was not statistically significant.

From these findings, the researchers conclude that these youngest HIV patients are a particularly socially vulnerable group: not only are they young, but most of them are female and many of them are pregnant, single, and unemployed. It is already well established in other research that being young, female, and unemployed increases the odds of sexual contact with older HIV+ men. This may explain the gender disparity in young diagnoses. The high drop out rate in this group could be the result of embarrassment (or denial),  lack of access to transportation, child care responsibilities, or migration (moving to find a job). Also, the high drop out rate is worrying from a prevention perspective. If HIV+ individuals are sexually active while not receiving treatment they are more likely to spread HIV to others. Also, with so many of the young patients women, mother-to-child transmission is also a concern.

What are my conclusions?

Even though a large number of medical records were examined, it was hard for the researchers to identify a single cross-country pattern in the data. This could be a side effect of the preliminary nature of these findings, or it may be due to complications and confounding factors beyond the scope of this study. But from what patterns we can see, it appears that young women are at much greater risk for contracting HIV than their young male counterparts. This could be the simple, unfortunate result of biology: it is much easier for the penetrating partner to give HIV than to get HIV, and this puts straight women at a disadvantage compared to straight men. But I worry that a large part of this disparity could be due to a lack of sexual agency among young women in these countries (compared either to straight men in these countries or women in western countries). These women could be less able to say "no thank you" or "wear a condom" to HIV+ men who want to sleep with them.

Based on these researchers' findings I think it is important to do more work to look at why different countries had different drop-out rates and why patients in each country are dropping out. A better understanding of these factors could lead to changes in how the treatment facilities function that could improve patient retention. If patient retention is improved the spread of HIV can be slowed. Though I think the most effective ways to slow (stop?) the spread of HIV in these countries will also have to include changes to the economic status of young women.  If economic policy changes can give young women more access to education and good jobs they will have more personal agency is all parts of life and be better able to protect themselves and their children (if/when they have them).

References

Auld, Andrew F., et al. "Antiretroviral Therapy Enrollment Characteristics and Outcomes Among HIV-Infected Adolescents and Young Adults Compared with Older Adults—Seven African Countries, 2004–2013."