This thesis is submitted for the postgraduate degree of a Master of Science by Research. It was undertaken as part of an Academic Foundation Year 2 junior doctor post in Ysbyty Gwynedd, Wales. As well as answering a novel research question, the Academic Foundation programme was designed to allow me to develop both my academic research skills and to develop my clinical skills as a junior doctor. Thus, I completed three sequential clinical rotations of three days per week for four months each, and in parallel one academic rotation of two days per week for a period of one year.

This thesis answers the question, “Does physical exercise affect cognition in patients living with Chronic Kidney Disease?” It comprises of a brief general introduction to provide background and context, a single chapter describing the research carried out, and a brief general conclusion.

Cognitive impairment is a significant burden on health and social systems globally. Those with Chronic Kidney Disease are more likely to have cognitive impairment than those without. Regular physical activity has shown a correlation with maintaining cognitive function, both in the general population and in people living with Chronic Kidney Disease. Many trials have investigated a link between exercise and improving cognition, but with varying results. This thesis summarises this existing research, using a systematic review and meta-analysis of randomised controlled trials.

The thesis findings suggest there is no clear evidence of beneficial effects of exercise on cognition in Chronic Kidney Disease, though there may be benefit in pre-dialysis patients and in those with kidney transplants, who can complete aerobic exercise at higher intensities than those patients receiving dialysis. These findings are based on subgroup analyses which include subgroups of n = 1 studies.

Future research would benefit from further investigating those patients who do not require dialysis, those who have undergone kidney transplantation, and using exercise interventions at higher intensities. It would also be useful for studies to have a longer follow-up period post-intervention, to investigate whether there is lasting benefit from said interventions