Hospital del Mar leads the way in avoiding fractures in HIV patients
Barcelona hospital develops technique to show bone problems in people with virus caused by infection and not antiretroviral treatment
Researchers and doctors from Barcelona's Hospital del Mar and its Medical Research Institute (IMIM) have that shown for the first time that bone problems and fractures in HIV sufferers are caused by the infection and not antiretroviral treatment, as was believed.
The study, published in the 'Journal of Antimicrobial Chemotherapy', used a bone-quality measuring technique designed in the US, and developed by Hospital del Mar staff, to show that the risk of fractures is related to the inflammation caused by the chronic infection.
The life expectancy of HIV sufferers has increased significantly thanks to antiretroviral treatments, but a side effect is that patients also develop other pathologies associated with the medication they have to take, such as cardiovascular, renal, or bone problems.
In these cases, tests show a decrease in calcium levels in the bone, which is an indicator of fracture risk. However, the new study indicates that this test by itself is not enough to predict whether the patient will go on to develop problems.
Dr. Güerri: "Antiretroviral treatment improves bone state"
According to Dr. Robert Güerri, an attending physician in the hospital's Infectious Diseases Service and the article's main author, the results of the work show that "it is the HIV itself that affects the bone, while the antiretroviral treatment improves bone state in patients."
"It is the HIV itself that affects the bone, while the antiretroviral treatment improves bone state in patients"
Dr. Robert Güerri · Researcher at Hospital del Mar
The researchers tested the bone health of 20 patients in treatment for HIV for over a year, and compared the results to that of non-sufferers. The conclusion is that the virus causes a chronic infection that triggers an immune system response involving inflammation.
It is this response that affects the health of the patients' bones, the researchers discovered. By lowering the viral load, antiretrovirals also reduce inflammation and, therefore, the risk of bone fracture.
"The antiretroviral treatment lowers bone mineral density, but bone quality, as we are improving the inflammatory state, actually improves," said Dr. Güerri.
The tests, performed for the first time, showed that the state of the patients' bones went from an average of 86, four points below that of the people in the control group without the disease, to reaching the same level as this group a year after starting treatment.
Pioneering microindentation test
The test uses a microindentation system, called OsteoProbe®, which measures bone hardness by hitting the tibia with a microneedle. Although invented by a physician in the US, it was Hopital del Mar that took the technique, adapted and developed it.
The study, which included research from Johns Hopkins University in the US, also indicates a possible therapeutic target, the Wnt (β-catenin) signalling pathway, to avoid bone problems in these patients, without the need to change their antiretroviral treatment.
Hailed as a change in how this problem is conceived and approached, a number of hospitals in other countries have already shown an interest in adopting the system and its application protocols, and have asked the Hospital del Mar staff for their help in using it.