Was Your Cognitive Disorder Misdiagnosed? You're Not Alone

HIV-associated cognitive disorder is a significant concern for those living with the virus, but U.K. researchers argue it’s being widely overdiagnosed. Clinicians from Brighton, England collected data from patients attending an HIV memory clinic and published their findings in Brain Sciences.

The team discovered that only a third of those attending Orange Clinic, a collaboration between local memory services and the Brighton and Sussex Medical School, truly met the criteria for HIV-associated neurocognitive disorder (HAND).

“HIV clinics have always been active in adapting and innovating care models to provide for the changing needs of their patients,” the study authors noted in a report by NAM’s AIDSMap. “The Orange Clinic represents such a model — a novel, needs-driven, efficient, and coordinated service for the aging population of [people living with HIV] who experience neurocognitive issues.”

Though cases of HIV-associated dementia have decreased after the rise of highly effective antiretroviral therapy, previous studies suggested that as many as a quarter of HIV-positive people aged 50 years and older could have at least a mild version of HAND.

Assessment for HAND is made using the Frascati criteria, an analysis of neuropsychological testing results. However, some researchers have pointed to a lack of precision within the criteria, which also does not take into consideration the complexity of pathogenic mechanisms contributing to cognitive impairment.

Regardless of the precise diagnosis, HIV-positive people with cognitive and memory problems require specialist support. HIV clinicians in Brighton therefore collaborated with local memory services and the Brighton and Sussex Medical School to establish a specialist clinic to assess, manage, and support HIV-positive people with suspected cognitive impairment.

Orange Clinic patients underwent a range of neuropsychological tests, including assessment of IQ, memory, attention, language processing, visuo-spatial processing, and executive function. Diagnoses are based on clinical interpretation of each individual’s test results, along with factors that can affect cognitive performance — including mood, mental health, and sleep.

Researchers in this study followed 52 people who received care at the clinic between June 2016 and May 2018. The median age of participants was 55 years old, while 79 percent were male, 83 percent were white, and the median time since learning their HIV diagnosis was 17 years. Only one person was not currently in treatment for HIV and only four others still had a detectable viral load. A third of the clinic’s clients reported recreational drug use. On average, the participants were taking five non-HIV medications. Additionally, 46 percent were also being treated with antidepressants.

According to the Frascati evaluation, a whopping 81 percent of those studied had HIV-associated neurocognitive disorder. However, when the clinicians used their own more sophisticated diagnostic criteria, the results were wildly different.

Under the newly refined criteria, only 31 percent were found to truly suffer from HAND while the others suffered from cognitive impairment due to other causes. Twenty-seven percent had a secondary mental health issue, such as depression, anxiety, drug/alcohol use, or poor sleep; 14 percent had a non-HIV-related cause, such as cerebrovascular disease or brain injury; and four percent were diagnosed with age-related dementia (one due to Alzheimer’s).

“It is significant that 27 percent of those who attended the clinic had a mental health condition, which was likely to be responsible for their objective cognitive impairment,” the study authors stated.

The authors suggest that HIV-related cognitive impairment has evolved along with the development of combination therapy. In the years before effective treatment, HIV-associated dementia was “characterized by progressive subcortical dementia with prominent degeneration of cognitive and motor functions.”

These days, people living with HIV are more likely to have their HIV in check — which leads to less cognitive damage — and they are less likely to be on medications that cause brain fog as a side effect. Researchers argue that those diagnosed with HAND have subtler memory impairments, as well as milder impairments to attention, visuospatial skills, and language.

The study’s conclusion immediately had real world consequences, when 23 people were determined to have been misdiagnosed and were discharged from the Orange Clinic. Nine were found to have no “objective” cognitive impairment; eight had impairment that was deemed due to mental health problems — which the clinic argued would be better treated more effectively elsewhere — and three were deemed to have such a mild form of HAND that they did not need treatment.