There are more than 1.2 million people living with HIV in the United States. An estimated 35,000 people will receive a new diagnosis each year. Many patients diagnosed with the virus when the epidemic first emerged are aging, and a new study finds that as they do, they have a higher risk of dementia.
Researchers with Kaiser Permanente say the overall incidence of dementias including Alzheimer’s has gone down in older Americans in recent years. The team wanted to see if HIV patients being treated with antiretroviral therapy (ART) were seeing similar numbers. Though these patients are also seeing a decreased incidence of dementia, the study – published in the journal AIDS – found that they still face nearly double the risk of developing dementia compared with the general population.
Dr. Jennifer Lam, first author and staff scientist with the Kaiser Permanente Division of Research, says, “People with HIV are getting older and aging-related conditions like dementia are becoming more common. It will be important to better understand factors that may be contributing to persistently elevated dementia risk among ART-treated people with HIV.”
To investigate the risk, the team looked at 16 years of Kaiser Permanente patient data from more than 13,000 HIV patients aged 50 and older on ART, with more than 154,000 people without HIV who were similar demographically. With these records, they discovered that 2.5% of the people in the HIV group had been diagnosed with dementia, compared with 1.3% of those without HIV.
The study didn’t uncover the reason for this difference. However, Dr. Lam said there could be a variety of factors, including length of HIV infection, type of HIV medication, HIV-related inflammation, or impacts of the disease that ART cannot treat.
Until the reason can be determined, the team says HIV patients should still be sure to follow recommendations for the general population.
Dr. Craig E. Hou, co-author and neurologist with The Permanente Medical Group, says, “Emerging data is confirming the higher risk of dementia in people with HIV. But the field does not yet know why that is or what is causing the higher risk. Therefore, advice regarding cognitive and brain health remains general and applicable to all people. We encourage people to eat a heart-healthy diet, stay physically active and engage in ongoing intellectual and mental activity.”
Though the higher risk is concerning, the study also found some good news. The incidence of dementia has gone down an average of 8% every two years for people with HIV, as the general population has seen a 3% decrease. The researchers say the decrease in HIV patients could be due to HIV treatment improvements, better chronic disease management, and efforts to get patients to stop smoking and get their blood pressure under control.
Dr. Michael Silverberg, senior author and research scientist with the Division of Research, says, “While the improvements are encouraging, there is still work to do given the persistently higher risk of dementia in this high-risk population.”
Going forward, the team plans to investigate HIV- and non-HIV-related risk factors for dementia, as well as how other conditions related to aging could play a role in HIV dementia risk.Whizzco