Phd ceremony A.J. Kwakernaak: Pathophysiological aspects of lifestyle and the kidney

The general aim of this thesis was to explore the relevance of selected lifestyle factors in the establishment, progression and treatment of chronic kidney disease. First we investigated the association between body composition parameters - muscle mass, fat mass and body fat distribution - as a proxy of lifestyle, and outcome in renal patients. We found that lower muscle mass is independently associated with a higher mortality risk, and that overweight/obesity and body fat distribution are associated with an increased risk of renal damage. We furthermore found that subjects with obesity or a central body fat distribution have an increased blood pressure in the small renal arteries which contributes to long-term renal damage. This is the first human evidence of an association between renal blood pressure and renal outcome. To test whether intervention in lifestyle can alter renal disease progression, we studied the effect of sodium restriction. We found that sodium reduction has a pronounced effect on blood pressure and albuminuria, as well as on inflammation/fibrosis and lipoprotein metabolism in renal patients. Taken together, we conclude that lifestyle intervention is a feasible and elegant measure to treat disease progression in renal patients.