Since the early days of the AIDS pandemic, much of the focus has settled on the effect that the disease had on the young. When previously healthy, young adult gay men began showing up in hospitals around the country with a baffling, and usually fatal new disease, the tragedy of life lost early was palpable. When the disease soon appeared in newborns and children, even those unsympathetic to the plight of gay men felt the sting of HIV. While this sad dynamic remains all too real today in many areas of the world, a different HIV infected population is growing more prominent throughout the developed world -- older people living with HIV.
The aging population of people living with HIV in the US is the result of several factors. First and foremost, the advances in care and treatment have allowed people to live longer and healthier with HIV. Life expectancy for people with HIV is now measured in decades rather than years. In fact, at a recent Project Inform public meeting, a leading HIV doctor told the audience that there was no fundamental reason for people with HIV not to expect to live a normal life span.
Another important factor is the aging of the US population in general. According to the US Census, people over 50 made up over 27% of the population in 2000. This is expected to grow to over 35% by 2025 as the so-called "baby boomers" age. This is mirrored in the statistics of people living with HIV. In the first half of the 1990s, the number of AIDS cases in people over 50 grew at twice the rate of the general population. This trend is likely to continue, if not accelerate as the population ages.
Some also think that the widespread use of impotence drugs such as Viagra in this population contributes to new infections among older people. Few prevention efforts have been aimed at older people. Widely held assumptions about sexuality and drug use have contributed to a lack of targeted messages. New treatments for sexual dysfunction, as well as the recreational use of these drugs and other factors, have likely contributed to a growing of newly infected people over 50.
Whatever the causes, there's clearly a growing population of people over 50 living with HIV. With much of the focus of research and services having been on younger people, issues unique to this population are growing in importance. Several areas are of particular interest to Project Inform: the growing complexity of drug interactions in older people; the immune system and aging; the difficulty of distinguishing between the consequences of aging and HIV-related conditions; and access to care and treatment. Over the next few months, we will present more in-depth articles on each of these important areas.
There's a pressing need for more targeted medical research on HIV and aging. There are many areas appropriate for specific research in older people with HIV. Broadly, they can be put into two categories: the impact of aging on HIV disease and the impact of HIV on aging. Within these broad categories there are many possible avenues of research.
Fundamentally HIV/AIDS is a disease of immune dysfunction. It is a complex disease with many important areas not fully understood. Some of the most fundamental questions of how HIV causes disease are far from settled. This is further complicated when considering older people with HIV, as there has been too little research in this group.
It is well documented that a person's immune system declines with age. This decline is seen in all major areas of immune function, from how immune cells communicate with each other to wide scale changes in immune organs themselves. However, the study of the immune system lags well behind other areas of medicine -- a gap that has closed notably in large part due to research spurred by the AIDS epidemic.
How exactly do these two immunologic processes, aging and HIV disease, affect each other? This is an area ripe for research. Our understanding of the function and activity of the immune system grows over time, with careful and innovative research. To gain a meaningful and practical understanding of the interplay between aging and HIV on the immune system, this research is absolutely necessary. The insights gained are likely to benefit everyone living with HIV, as well as everyone growing older.
One area where aging and HIV treatment intersect is around drug interactions. As people age they tend to take more prescription drugs. Drugs for elevated cholesterol, hormone deficiencies, digestive problems, high blood pressure and other conditions are more widely used by older people. This makes avoiding and managing drug-drug interactions that much more challenging. This problem is likely to grow more difficult as the population of older people continues to grow -- and the pharmaceutical industry develops new therapies to address the health problems of aging.
Drug interaction studies need to be done between HIV drugs and drugs widely used by people over 50. However, this might not be enough. In general, drug interaction studies are done between two drugs at a time. This often does not reflect the real life situation of people taking many drugs together. Knowing how three, four or more drugs will interact is not always as simple as looking at whether any pair of those drugs is known to have an interaction. The interaction of HIV drugs and the drugs of aging are quite complicated when a person's HIV regimen includes a drug like ritonavir, which greatly changes the way the liver clears many drugs from the blood.
It is equally important to understand the role that HIV disease plays on the process of aging. HIV infection, as well as the treatments used against it, may significantly impact some of the normal processes of aging. This has already been suggested in that several of the diseases that continue to vex people living with HIV, despite successful anti-HIV therapy, are diseases of older age. Specifically, people with HIV are at an increased risk of heart disease, diabetes and cognitive dysfunction -- all hallmarks of aging. HIV itself and HIV drugs are also tied to metabolic syndromes, which increase in frequency and severity with age.
This is far from an exhaustive discussion of the needs of people over 50 living with HIV. There are many other issues -- including prevention methods, nutrition, psychosocial support, autoimmune illnesses like arthritis, stigma and sexuality. This article is meant to open a much wider and in-depth discussion of HIV and aging. Even the bio-medical topics mentioned are only a sampling of the many unanswered questions on this topic. Only dedicated research on these areas and others will get the answers that this growing population needs.
The bulk of research to date has focused on the disease in children and younger adults. The remarkable advances in treatment have led to many people living longer, healthier lives with HIV. As more people infected in their 40s now enter their 50s and beyond, the opportunity for specific research grows along with it. Project Inform advocates for research on this area of increasing importance, so people with HIV can live productive and healthy lives well into older age.
The National Association of HIV Over Fifty (NAHOF) is an organization dedicated to education and advocacy around all issues, from prevention to care and treatment, for people over 50 living with HIV. For more information, visit www.hivoverfifty.org or call 617-233-7107. You can also read Project Inform's article on HIV and Older Age.