Sexually transmitted infections (STIs) could lead to more than just an awkward chat with your latest fling.
Research suggests that certain STIs can increase your chances of developing dementia, a memory-robbing disease that affects one in 10 older adults in the US.
That’s troubling, considering STIs are booming across the country, with more than 2.4 million cases reported in 2023 alone. Even more concerning, infections in adults aged 65 and older have more than doubled over the past decade.
With research showing that older adults are less likely to get regular STI screenings and many healthcare providers neglecting to discuss sexual health with these patients, the age group may be particularly vulnerable to long-term effects like cognitive decline.
Here are four STIs that could increase your chances of developing dementia.
If you thought herpes was just a case of pesky cold sores, think again.
Between 50% and 80% of Americans have oral herpes (HSV-1), and 1 in 6 people aged 14 to 49 in the US have genital herpes (HSV-2), according to Johns Hopkins.
But here’s the kicker: The virus responsible for herpes can enter the brain and lie dormant, only to reactivate later. When it does, some studies suggest it could trigger inflammation in the brain, potentially damaging brain cells and increasing the risk of dementia.
In fact, people with HSV-1, HSV-2, or both, are up to 2.44 times more likely to develop dementia compared to those who have never been infected, according to a 2024 study from the University of Texas Medical Branch.
“These findings underscore the need for more research into the mechanisms underscoring HSV contribution to cognitive decline and whether such mechanisms can be targeted as a preventive strategy against dementia,” said Dr. Giulio Tagliatlalasenior author and director of the Moody Brain Health Institute at UTMB.
Syphilis is making a big comeback in the US, and it’s not just affecting the younger crowd: Cases among adults aged 55 and up have increased by nearly 700% since 2010.
While syphilis is treatable with penicillin and other antibiotics, if it’s not addressed, the infection can impact any and every organ system. One particularly serious complication is neurosyphilis, where the bacteria invade the brain and spinal cord, causing inflammation and damaging brain tissue.
In its later stages, neurosyphilis can lead to syphilitic dementia, which typically develops 10 to 25 years after the initial infection. Symptoms include memory loss, confusion, personality changes, trouble concentrating, depression and even delusions.
The good news? Experts say that neurosyphilis- dementia is “potentially reversible,” but only if it’s caught and treated early.
The CDC estimates that around 400,000 people in the US are living with genital warts at any given time.
Genital warts are a common STI caused by certain strains of the human papillomavirus (HPV). HPV can contribute to brain inflammation, a major factor in the development of dementia.
A 2020 study using health insurance data from 16,000 patients in Taiwan found that individuals with genital warts caused by HPV had a 49% increased risk of developing dementia. Research also shows that cervical cancer, linked to HPV, is associated with a heightened risk of dementia.
Luckily, the HPV vaccine protects against the strains responsible for the majority of genital warts, and it’s highly effective in preventing both genital warts and cervical cancer.
Nearly 1.2 million people in the US are living with HIV.
When the virus spreads to the brain, it triggers inflammation, damages brain cells and releases harmful toxins — all of which contribute to cognitive decline and, in severe cases, can lead to HIV-associated dementia.
In a 2022 studyresearchers compared 13,000 Kaiser Permanente patients with HIV to over 155,000 people without the virus. They found that 2.5% of those with HIV were diagnosed with dementia over a 16-year follow-up period, compared to just 1.3% of those without.
On average, people with HIV were diagnosed with dementia 10 years earlier than those without the disease.
“Effective medications have transformed HIV into a manageable condition for most patients,” said Dr. Jennifer Lama research scientist for the Kaiser Permanente Division of Research who led the study. “That’s why it’s important to address the health concerns that come with aging.”
