Pioneering research on drivers with HIV and metabolic syndrome

HIV and metabolic syndrome (MetS), specifically diabetes and hypertension, are highly prevalent among vocational drivers, for example truck drivers. These conditions have been associated with neurocognitive decline in the domains of attention, executive function and processing speed. As a result, these conditions can negatively impact driving performance and may lead to unemployment and early retirement.

UCT's Dr Hetta Gouse will tackle much-needed research and neuropsychological testing for these vocational drivers, thanks to a prestigious Emerging Global Leader Award from the Fogarty Institute for Innovation in the US.

The award is something of a coup for Gouse, a neuropsychologist who was recently promoted to chief research officer in the Department of Psychiatry and Mental Health. The award, which is rarely given to first-time applicants, required an exhaustive (and exhausting) proposal to get her to home base.

But she had seen the huge gap in knowledge and research in the area − and that was worth pursuing.

Impact on society

“As HIV and metabolic syndrome become more prevalent in South Africa, and may co-occur, we need to understand how they impact on society,” Gouse wrote in her grant proposal.

Because of the benefits of antiretrovirals and metabolic treatments, more and more people affected by these conditions are able to remain in, or return to, employment.

But the neurocognitive disorders associated with both conditions can still affect aspects of their daily functioning and work performance. It's here that the knowledge and research gap is most visible.

“Despite this lack of knowledge, occupational health professions are required to provide services to people living with these chronic conditions,” said Gouse.

The research bridges the divide between occupational health and neuropsychology. It addresses vital health questions around treatment, public safety and an enhanced quality of life among the affected drivers.

Although routine screening for these conditions rarely happens, they can improve with treatment, she says. With metabolic syndrome, timeous treatment may even prevent the early onset of cognitive impairment.

A fine art graduate and jewellery designer in an earlier chapter of her life, Gouse says that her abiding interest in psychology eventually saw her sell off her goldsmithing tools. She returned to UCT to learn a wholly new professional skills set and language, obtaining her PhD in research and clinical neuropsychology.

It was her work at primary health clinics that first alerted her to the medical staff's lack of knowledge and training around cognitive disorders − and particularly their knowledge about vocational and functional ability among people living with HIV/AIDS. This is an area traditionally addressed by occupational health practitioners.

Realising that there was a gap to be urgently filled, Gouse trained her focus on the impact of cognitive impairment associated with chronic conditions in the workplace.

Driving simulator

The starting point for developing effective treatment plans is determining the rates and presentation of cognitive impairment related to HIV and MetS in vocational drivers. A driving simulator is a safe and effective proxy for gaining insight into driving performance, so Gouse led efforts to secure a University Research Committee Equipment Grant for a driving simulator in the department.

Participants complete three interactive driving sessions on a simulator that's modelled on the inside of a VW Polo 1.4. Three side-by-side monitors provide participants with a 180-degree field of view. The simulations reflect real-world driving situations with South African road conditions. Each driving simulator assessment takes approximately one-and-a-half hours.

Previous simulator research by Professor Thomas Marcotte of the University of California, San Diego, showed that cognitively impaired individuals displayed greater 'swerving' within their lanes and caused more crashes. They also had poorer navigational skills. Impairment in the areas of executive function, attention and processing speed are associated with poor performance in simulator testing. During on-road driver testing, impaired participants were classified as unsafe at a higher rate than those who weren't.

The aims of Gouse's research are to guide the development of a standardised assessment instrument that can provide reliable and valid measurements of the neurobiological consequences of HIV and MetS; to provide screening guidelines that will ultimately result in improved treatment practices with employees being retained in the workplace for longer; and to develop rehabilitative interventions for employees with cognitive impairment.

“In turn, this has the potential to improve health, lengthen life and reduce the individual and social burdens of illness and disability,” she added. “I also want to emphasise that HIV and MetS are not themselves risk factors for driving. Only individuals who present with cognitive impairment associated with these conditions may be at risk, and then also only a sub-population of those individuals.”

Building capacity

Beside the funding component, the Emerging Global Leader Award targets research scientists in junior faculty positions in low-and-middle-income countries, providing capacity building where it's most needed. It provides salary and research support and ensures protected time for the researcher, which are all essential for career development.

But there's an even larger picture.

The Fogarty programme will also groom Gouse to become the first local expert in this pioneering, cross-disciplinary field, with the prospect of becoming a global leader in this research area.

“We'll be the first to develop a programme of research in this field and it will be the first study that is evidence-based rather than relying on anecdotal reports of the impact of HIV-associated neurocognitive disorders and MetS-associated neurocognitive disorders on professional drivers' performance.”

As Gouse wrote in her proposal, “It will inform patient care and employee management, resulting in better safety and enhanced quality of life.”

Mentors

Gouse will be supported by two primary mentors and four co-mentors.

The first is Marcotte, who is the manager of the HIV Neurobehavioural Research Centre (NHRC) at the University of California, San Diego. He is an expert in the neuropsychology of HIV infection, the impact of mild cognitive deficits on everyday functioning, and behavioural interventions that improve real-world performance.

The second is Professor Leslie London, Head of Public Health Medicine in the School of Public Health and Family Medicine. London is a specialist in public health medicine with research interests in the ethics of public health policy and conflicts of interest and human rights in health systems.

Gouse's co-mentors are Professor John Joska (UCT), Professor Kevin Thomas (UCT), Dr Greg Kew (UCT and EOH Health) and Professor Reuben Robbins (Columbia University, New York).

Story Helen Swingler. Photo Michael Hammond.