HIV and cardiovascular disease
Many people (estimates suggest about half of the UK’s general population) are infected with cytomegalovirus (CMV), which is a herpes virus. In most people it doesn’t cause any symptoms, but it can cause serious illnesses in people with a suppressed immune system, including HIV-positive people with a very low CD4 cell count.
Research conducted in HIV-negative people has shown that infection with CMV can increase the risk of cardiovascular disease.
Researchers in the US wanted to see if there was a link between the infection and some early warning signs of cardiovascular disease in HIV-positive women.
They used ultrasounds of the carotid artery to check for key early warning signs of cardiovascular disease. Blood tests were used to monitor levels of antibodies to CMV.
They found a clear relationship between antibody levels and hardening of the arteries. The doctors believe that CMV could be causing inflammation, therefore increasing the risk of cardiovascular disease.
Their results also showed that higher levels of CMV antibodies were associated with lesions in the carotid artery, but only for women taking HIV treatment who had an undetectable viral load.
The researchers think this could be due to immune reconstitution inflammatory syndrome (IRIS). This is a temporary worsening of pre-existing and often latent diseases during the early stages of HIV treatment, particularly seen in people starting treatment when their CD4 count is already very low.
Further research is needed into this apparent association between CMV and cardiovascular disease.
Monitoring of cardiovascular health is an important part of HIV care. This means that problems can be spotted early and appropriate treatment and advice can be offered. There are several ways you can improve your cardiovascular health and reduce the risk of problems developing – these include stopping smoking; taking regular exercise and eating a balanced diet.
HIV and TB
With the right treatment and care, TB can almost always be cured, but TB is still the single most important cause of serious illness and death in people with HIV. So it’s important that doctors have a clear understanding of its risk factors.
Therefore, researchers looked at the medical records of approximately 65,000 people who received HIV care in Europe and the US between 1996 and 2007.
During a period lasting a little over two years, approximately 700 people developed TB.
Results showed that people who started HIV treatment were 44% less likely to develop TB than people who were not taking HIV treatment.
However, they found rates of the infection were much higher in people with the lowest CD4 cell counts (below 50), compared to people with stronger immune systems. It’s well known that a weak immune system is a major risk factor for TB.
Older age – defined as above 50 years – was also associated with an increased risk of TB.
There was also evidence that some patients developed TB in the first three months of HIV treatment because of IRIS (see above). This form of TB needs expert management and care. Longer-term HIV treatment was associated with an overall reduction in the risk of the infection.
For more information on tuberculosis, you can find our HIV & TB booklet online at www.aidsmap.com/booklets.