Monday, July 25, 2016

NOT SO FAST


Do people with HIV really experience accelerated aging?

by David Alain Wohl, MD

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Recent talk about HIV and aging has almost always been scary. A number of studies conclude that people living with HIV have so-called “accelerated aging”—meaning they will suffer heart attacks, strokes, cancers, and osteoporosis more often and sooner than those without HIV. Reading and hearing about these concerns can be disheartening, especially for those who have fought so hard, over so many years, to control their HIV.

Well, this is one article on aging and HIV that will challenge the concept of people living with HIV having an early expiration date. Instead, we can look at what we know and what we don’t, to get a better idea of what the risks are for HIV-positive people growing older—and what they can do about them.

FACT: HIV-positive people have higher rates of age-related conditions.

HIV-positive people are definitely at increased risk of cardiovascular disease, certain types of cancers, neurocognitive impairment, and weaker bones (collectively what I will call “age-associated badness”). I know, that is a pretty gloomy realization to start with when trying to argue that HIV infection does not lead to accelerated aging. However, what the statistics show us is that people living with HIV have a greater chance of these serious problems, to a large extent, because they are more likely to have the traditional risk factors for each of these conditions—the factors that are seen in the general population as the main drivers of such conditions. 

For example: People who smoke, don’t exercise, eat unhealthy diets, and live with high levels of stress are more likely to have cardiovascular disease than those without these risks. Rates of smoking alone are up to three times higher among HIV-positive people than in the general population. It is not a stretch to say that people living with HIV are also more likely to experience those other traditional risks. Therefore, it follows that people with HIV would have more heart attacks and strokes—and they do.

The same goes for cancer, cognitive concerns, and brittle bones. Mental illness, substance abuse, and head trauma can lead to cognitive issues, and those are risks that people with HIV more often have. While a number of studies have shown HIV to be associated with low bone density, a recent study of HIV-negative men enrolled in a study of pre-exposure prophylaxis (PrEP) found higher than expected rates of bone density problems in these men before they started on the study drug. Alcohol and methamphetamine use were both associated with more brittle bones.

Certainly, researchers try to account for imbalances in risk when comparing HIV-positive and HIV-negative people. The problem is that it is hard to account for all of the most potentially influential factors, let alone those that are less obvious. Depression, poverty, discrimination, and certain types of substance use have been linked to poor health outcomes, but are hard to measure and are not typically included in these adjustments. We are left with possibly comparing apples to oranges when comparing HIV-positive and HIV-negative people, and attributing excess risk to the virus or its therapies rather than an unaccounted-for imbalance in other risk factors.


FACT: The rIsk of age-related badness can be reduced.

In contrast to the notion that the development of age-related badness is a foregone conclusion, people living with HIV often have the power to tilt the odds in their favor by taking action. Not all risks can be eliminated, for sure. You can’t take back 30 years of smoking, but you can stop smoking. Moreover, you can also reduce your risks in very traditional ways. 



Heart disease risk

Like any aging American, people with HIV should have their risk of cardiovascular disease assessed by their clinician. Using cholesterol values, blood pressure readings, age, race, and diabetes and smoking history, the 10-year and lifetime risk for cardiovascular disease can be easily estimated based on data from huge numbers of people (yes, there is an app for that). This risk score can inform recommended interventions—from doing nothing, to making dietary changes and exercising, to starting medication. 

Cardiovascular disease risk can absolutely be reduced, with lifestyle changes, as mentioned; better control of blood pressure and blood sugars; and in many cases medication, particularly drugs like lipid-lowering statins or aspirin. Recent data even show that rates of heart attacks and strokes among HIV-positive people in care have dropped and are now about the same as those for HIV-negative people. This has been attributed to some of the factors I’ve mentioned, including smoking cessation, control of cholesterol and blood pressure, and the push for an earlier start of HIV medications.

Bone loss risk

For bone health, a similar calculator can be used to assess the risk of osteoporosis; and action can translate into risk reduction. There are guidelines for when to measure bone density using X-rays called DEXA scans. Older people living with HIV should ask their health care providers about whether they need a DEXA scan or not. When low bone density is identified, it can sometimes be explained by low vitamin D or testosterone levels. Simple supplementation with vitamin D and calcium can help improve bone health; stronger medications can be used for more severe cases.

Cancer risk

Another way that HIV-positive people can help make sure that the force of prevention is with them is to get the recommended routine cancer screenings. Recommendations are pretty clear about screening for cancer of the colon, breast, cervix, lung (for those with significant smoking history), and liver (for those with cirrhosis and hepatitis C or B). Early detection of these cancers can lead to early treatment and, in many cases, cure.

Too often people, with and without HIV, stall on getting potentially lifesaving colonoscopies or mammograms. Not a good idea. These screenings are notorious for causing discomfort, but you have gone through worse. Take a deep breath, and get screened.

A few more ounces of prevention

We should not short-change other interventions that help people stay healthy as they age. These include basic things, like vaccinations. Many people don’t get the influenza vaccine, believing it will make them sick—placing themselves and others, including children, at risk for this potentially devastating infection. The flu shot cannot cause the flu (it is an inactive vaccine—not alive!). We should all get it every year. Other important vaccines include those for strep pneumonia and shingles.

Other no-brainers when it comes to aging well with HIV include good recordkeeping of all medications, even over-the-counter and alternative ones. Bring a list of all your drugs and supplements to the clinic to help your health care providers avoid drug interactions or errors that could be harmful.

Older people also have sex, thank goodness, and no one should age out of asking about and being screened for sexually transmitted infections.

Lastly, depression is highly prevalent among people with HIV, as well as older folks. This needs to be looked for and addressed. Besides medicine, social support can help and is critical to well-being. (Check out the conversation between David Fawcett, PhD, LCSW, and Gina Brown, MSW, about social isolation among older adults living with HIV, later in this issue.)

Fact: Studies show higher levels of markers of inflammation in people living with HIV, and these are associated with age-related badness.

Inflammation is our body’s way of responding to damage or threats. Hit your thumb with a hammer and you get lots of inflammation in your thumb. This is because damaged cells sent signals to other cells that something harmful happened and needs to be dealt with. Less obvious is inflammation that occurs in response to more chronic insults like bad gum disease, high-fat diets, or infection with HIV. Here, too, signals are sent and can provoke responses that, unlike the sore thumb, persist, keeping the body in an active state of response that can hurt organs over time.

A number of studies have shown that HIV-positive people in general have higher levels of markers (signs) of inflammation than those without HIV. Studies of patients with undetectable viral loads on HIV medications show that levels of inflammation markers are closer to normal but, in general, are still somewhat higher than for those who are HIV-negative.

Note the use of “in general.” This is to make loud and clear that these studies do not show that all people with HIV have high levels of inflammation. In fact, the studies looking at this have found a range of inflammation among HIV-positive people with many (maybe most) having low levels of inflammation. It is only when they look at overall averages that they can see differences between groups. 

Additionally, it is unclear what these levels of inflammation really mean, as they can change over time and we don’t know for certain what is a good, concerning, or dangerous level of inflammation markers. It is also hard to know to what extent any of the inflammation seen in these studies is due to HIV, HIV medications, or something that is more unique to HIV-positive people. There may be a role that the virus continues to play, even when controlled, that contributes to age-related badness, but with so much else going on, it is hard to say how big this role is.

Actions that can help reduce inflammation include the usual suspects: good diet, good weight, good exercise, good control of diabetes, good control of blood pressure, and so on. HIV therapy itself (especially started early, before CD4+ cell count declines) reduces levels of inflammation markers—likely by controlling the virus—and that may be the most important intervention of all for HIV-positive people getting older.

Conclusion

People living with HIV are not powerless against the onslaught of age-related badness, and need to be proactive regarding their health as they get older. Ask your health care providers about assessments of risks for cardiovascular disease and low bone density. Screening for cancers is a must.

On the other side of the stethoscope: Older HIV-positive people must take good care of themselves, physically and mentally. This means eating healthily, exercising, managing problems such as obesity, diabetes, and high blood pressure, getting all recommended vaccinations, and using care to avoid sexually transmitted infections.

For all the handwringing about HIV and aging, we cannot lose sight of the facts: The survival rate for people living with HIV in the U.S. is now incredibly close to that of the general population. That does not mean we know it all, but it means a lot.

David Alain Wohl, MD, is a professor of medicine in the Division of Infectious Diseases at the University of North Carolina (UNC). He leads the UNC AIDS Clinical Trials Unit at Chapel Hill.

Read more articles here: Positively Aware

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