Reducing sodium intake may provide significant improvements in kidney and heart health among patients suffering from chronic kidney disease, new research has found.The study showed that in patients with chronic kidney disease, dietary sodium restriction reduced albuminuria -- an indicator of kidney dysfunction -- and blood pressure levels, whereas paricalcitol -- a vitamin D receptor activator -- in itself had no significant effect on these measures.However, the combination of paricalcitol and a low sodium diet resulted in the lowest albuminuria levels in patients."The study found that sodium restriction provided a relatively large beneficial effect, whereas the effect of paricalcitol was small. Thus, the impact of the combined intervention was largely due to the protective effect of sodium restriction," said Martin de Borst from University Medical Center Groningen, in The Netherlands.Urinary excretion of proteins, including albumin, is an indicator of chronic kidney disease. Therapies that reduce such albuminuria can slow kidney function decline and also have beneficial effects on the heart and blood vessels, the researchers said. Unfortunately, currently available therapies do not eliminate albuminuria in many patients, leaving these individuals with what is known as residual albuminuria.The findings appear in the Journal of the American Society of Nephrology.