Viral heritability of neurocognitive performances in persons living with HIV and underlying viral residue variants
Can the genetic makeup of HIV influence brain health? New findings from the Swiss HIV Cohort Study
Modern HIV treatment allows people living with HIV to lead long and healthy lives. However, some people continue to experience difficulties with memory, concentration, or information processing, even when their HIV infection is successfully controlled by medication. Why some people develop these problems while others do not remains an important question.
A new study published in Brain Communications suggests that part of the answer may lie in the genetic makeup of HIV itself.
What did the researchers discover?
Researchers from the Swiss HIV Cohort Study (SHCS) and its associated Neurocognitive Assessment in the Metabolic and Ageing Cohort (NAMACO) investigated whether genetic differences between HIV strains are linked to brain function. The team studied 981 people living with HIV who underwent detailed assessments of their memory, attention, information processing, language, and other neurological functions. By comparing these results with genetic information from the participants’ HIV strains, the researchers found that people carrying genetically related viruses tended to show similarities in certain neurological abilities.
Their findings suggest that genetic differences between HIV strains may account for around one-quarter of the variation in certain neurological functions, particularly information processing speed, movement, and sensory abilities. This is an important discovery because it suggests that neurological health in people living with HIV may depend not only on individual factors, such as age, general health, or treatment history, but also on characteristics of the virus itself.
What does this mean for people living with HIV?
The results provide new insight into why some people experience neurological difficulties despite receiving effective HIV treatment.
Importantly, the study does not suggest that people carrying particular HIV strains will necessarily develop cognitive problems. Brain health is influenced by many factors, and the findings do not yet allow doctors to predict an individual’s risk. However, the research opens the possibility that, in the future, information about the genetic makeup of HIV could help doctors identify people who may benefit from closer neurological monitoring or targeted preventive measures. The findings also reinforce an important message: successful HIV treatment is essential, but understanding long-term health requires looking beyond viral suppression alone.
Why was the Swiss HIV Cohort Study essential?
This discovery was possible because of the unique research infrastructure of the Swiss HIV Cohort Study.
For decades, the SHCS has brought together people living with HIV, healthcare professionals, and researchers across Switzerland. Through regular medical follow-up, the systematic collection of health information, and the careful storage of biological samples, it provides an exceptional resource for investigating the long-term consequences of HIV infection.
In this study, researchers combined information from the SHCS with detailed neurological assessments collected through NAMACO and genetic analyses of HIV. This combination allowed them to investigate a question that would be extremely difficult to answer through routine clinical care or a short-term research project.
The study also builds on earlier SHCS research linking genetic differences between HIV strains to self-reported memory and concentration difficulties. The new findings strengthen this evidence by using standardized neurological tests.
The SHCS demonstrates how long-term collaboration between patients, clinicians, and scientists can generate knowledge that would otherwise remain out of reach.
Looking ahead
Further studies are needed to confirm these findings, understand how HIV genetic differences might affect the nervous system, and determine whether they can eventually improve patient care.
For now, the study represents an important step towards a more complete understanding of brain health in people living with HIV.
Above all, it highlights the lasting value of the Swiss HIV Cohort Study. The continued participation of people living with HIV makes it possible to answer increasingly complex questions, improve our understanding of the disease, and work towards better long-term health outcomes.