Prof Sam Nightingale

RAD Associate Fellow

University of Cape Town

Sam Nightingale is an Associate Professor of Neurology at the University of Cape Town. After training in the UK, Sam became interested in brain infections and global neurology. He is now based in South Africa where his research focusses on the effect of HIV on the brain. He has established a new framework to categorise cognitive impairment in people with HIV, chairs the International HIV-Cognition Working Group and is PI for the CONNECT study, investigating a large cohort of people with HIV in Cape Town. He is particularly interested is what studying ageing people with HIV can tell us about the mechanisms underlying Alzheimer’s disease.

Research summary

Despite extensive research, the cause of Alzheimer’s disease is still not known. Amyloid protein accumulates in the brain of those with Alzheimer’s disease, however we do not know why the body produces amyloid to start with. Whilst not yet proven, it has been proposed that amyloid is a response to inflammation and infection in our brains, trying to patch up damaged areas as we grow older. Examining older people with HIV provides a unique opportunity to test this theory.

Following the remarkable success of antiretroviral treatment, people with HIV are now living into older age. A recent study found 5% of people over 70 years old in South Africa are living with HIV. HIV can affect the brain, leading to chronic inflammation. It is not yet known whether this leads to a higher risk of Alzheimer’s disease for older people with HIV. If it does, this suggests something important about the cause of Alzheimer’s disease, which could lead to treatment or prevention for this devastating condition.

Professor Nightingale has designed a case-control study of 250 people over 70 years of age. Half will be people living with HIV (cases) and the other half will be HIV-negative people from a similar background (controls). The hypothesis is that those with HIV will have more amyloid protein in the brain as indicated by spinal fluid tests, and a higher prevalence of Alzheimer’s disease.