There is an apparent link between HIV and a lowered risk of developing multiple sclerosis (MS). Publishing their findings in the Journal of Neurology, Neurosurgery & Psychiatry, researchers conducted an observational study of people hospitalized in England between 1999 and 2011. They compared 21,000 HIV-positive people with a control group of nearly 5.3 million HIV-negative people.

The HIV-positive people were 62 percent less likely to develop MS when compared with the control group. The greater amount of time that passed following an HIV diagnosis, the greater the apparent reduction in risk when compared with the controls. After more than a year, the relative risk reduction increased to 75 percent; after more than five years, the figure increased to 85 percent.

The researchers can only speculate about the reason for the reduction in MS risk. It is possible that the virus itself fights MS, or that antiretrovirals (ARVs) to treat HIV attack other viruses that have been shown to spur the development of MS. Unfortunately, there was no information about whether the people living with HIV were taking ARVs.

To read the press release, click here.

To read the study abstract, click here.