HIV and TB

It’s World TB Day today.

Worldwide, tuberculosis (TB) is the biggest single cause of illness and death amongst people with HIV. Its impact is especially severe in poorer countries that have been hardest hit by HIV. But TB is also one of the most common AIDS-defining illnesses diagnosed in the UK.

TB is treated with a combination of antibiotics. This treatment can cure TB. However, some strains of TB have become resistant to the drugs used to treat them, and these resistant strains may need more intensive therapy. New figures show that rates of drug-resistant TB are now at record levels, and many HIV-positive TB patients in South Africa have resistant strains.

Resistant TB is also a problem here in the UK. Recent research showed that a third of all TB cases in prisoners involve a strain of the infection that has resistance to at least one anti-TB drug.

As with HIV treatment, therapy for TB works best if you take your treatment properly. That means completing the full six to nine months of treatment, and taking all the doses correctly.

You can find out more about TB, HIV and treatment in NAM’s information booklet, HIV & TB . The booklet Adherence & resistance tells you more about taking your HIV treatment.

Body weight and HIV

How body-weight issues differ for HIV-positive patients in richer and poorer countries has been shown by two recent studies.

A study conducted in the US showed that obese patients have poorer gains in CD4 cell counts after starting HIV treatment than those of normal weight, or patients who are overweight.

By contrast, a study conducted in Zambia showed that low body weight is a real concern for people with HIV, and that patients who gained weight after starting HIV treatment had the best outcomes.

Wasting and a low body weight are linked to an increased risk of illness and death for people with HIV.

Muscle and modest amounts of fat provide reserves that help the body fight off, and recover from, infections.

But being obese (significantly over your ideal weight) has been linked to a number of serious health conditions. Some of these, for example diabetes, cardiovascular disease and kidney dysfunction, are now major causes of illness in people with HIV.

Rates of obesity are increasing in many western countries, most notably the US. Researchers from the US military wanted to see what impact obesity had on immune function in people taking HIV treatment.

They monitored the weight and CD4 cell count of over 1000 patients.

Their results showed that obese patients gained significantly fewer CD4 cells after starting HIV treatment than people who were of normal weight or who were moderately overweight.

About 1% of patients in the US study were underweight. Just like the people taking part in the study in Zambia, these patients did less well after starting HIV treatment than those with a healthy body weight.

Diet and exercise can help you achieve and maintain a healthy body weight.

There’s information about these subjects in the NAM booklet, Nutrition, and on namlife.org , a site especially for people with HIV.

Drug interactions

Like most medications, anti-HIV drugs can interact with other treatments.

This is because many anti-HIV drugs are processed by the body in the same ways as other medicines.

As a result, levels of drugs can be increased, meaning that there’s a greater risk of having some side-effects. Or levels of drugs can be lowered. This can mean that there isn’t enough of a drug in the blood to work properly.

Researchers have found that levels of the important drugs used to prevent malaria called atovaquone/proguanil (Malarone) are reduced by up to 75%  in people taking the anti-HIV drugs efavirenz (Sustiva, also in Atripla) , Kaletra (lopinavir/ritonavir) and boosted atazanavir (Reyataz).

The researchers are uncertain how important this finding is. There’s never been a recorded case of atovaquone/proguanil treatment failure in people who are also being treated with anti-HIV drugs.

But they recommend that people taking HIV treatment should make sure that they take all their doses of atovaquone/proguanil and ensure that they do this with their main meal of the day.

It’s usually possible to do something about interactions and the study underlines that it’s important to tell your HIV doctor or pharmacist about any other medicines or drugs that you are taking when you are prescribed a new drug.

This includes those prescribed by another healthcare professional, over-the-counter treatment (such as cold and flu remedies), herbal and alternative remedies, and recreational drugs.

You can find out more about interactions in the NAM booklets Adherence & resistance and Anti-HIV drugs, or on namlife.org .