Results of a study by researchers from the US Department of Veterans Affairs indicate that HIV and hepatitis C co-infection increased the risk of cognitive impairment. The researchers compared cognitive function of 19 men co-infected with hepatitis C and HIV, 17 men infected with hepatitis C alone (mono-infection), 14 men with HIV mono-infection, and a control group of 28 healthy men. All participants were 45-65 years old, and those with HIV were taking antiretroviral therapy and had an undetectable viral load. None of the participants had liver cirrhosis or clinical depression, and none were drug or alcohol abusers. The study evaluated participants for symptoms of depression, evaluated cognitive function in seven domains, and calculated an overall global deficit score.
Participants with co-infection had more symptoms of depression than those with hepatitis C mono-infection and the control group. Researchers found a mild but significant impairment in cognition among the co-infected individuals. Approximately 65 percent of co-infected participants were classified as impaired compared to 42 percent with hepatitis C mono-infection, 29 percent with HIV mono-infection, and 18 percent of controls. The individuals with co-infection performed poorly on attention, working memory, executive function, verbal learning and memory, and visual learning and memory tests. Their scores were significantly lower than those of controls or mono-infected participants. In the hepatitis C mono-infected participants, a higher hepatitis C viral load was negatively associated with attention, executive function, and speed of information processing. The researchers concluded that the effect of HIV and HCV co-infection may result in neuropsychological deficits in co-infected individuals and that high viral load in HCV mono-infection may impact cognition.
The study, “Differential Cognitive Impairment in HCV Co-infected Men with Controlled HIV Compared to HCV Mono-infection," was published ahead of print in the Journal of Acquired Immune Deficiency Syndrome, (DOI: 10.1097/QAI.0b013e31827b61f1, 2012).