Sodium intake may be linked with the changes that occur in the heart’s left ventricle of patients with chronic kidney disease (CKD). Interventions that reduce sodium intake, such as reducing the use of salt, might improve cardiovascular outcomes in these patients.
The study with these findings, “Skin Sodium Concentration Correlates with Left Ventricular Hypertrophy in CKD,” was published in the Journal of the American Society of Nephrology (JASN).
CKD patients have an extremely high risk of developing cardiovascular disease (CVD) compared to the general population, so much so that in the early stages of CKD, patients are more likely to die of heart disease than they are to progress to end-stage renal disease.
The increased risk of cardiovascular disease in patients with CKD is in part related to left ventricular hypertrophy (LVH), an enlargement and thickening (hypertrophy) of the walls of the heart’s main pumping chamber (left ventricle). But the biological mechanisms that lead to LVH in patients with CKD have not been fully understood.
Increased sodium intake is associated with increased blood pressure, and some studies suggest that sodium intake might be associated with left ventricular hypertrophy in patients with CKD.
Recent studies have shown that the skin and muscle may store sodium. In light of these findings, a research team led by Markus Schneider, MD, at the University of Erlangen-Nuremberg in Germany questioned whether sodium deposits in the skin would be associated to the degree of LVH in CKD patients.
The research team examined the content of sodium in the skin of 99 patients with mild to moderate CKD (42 women; average age of 65), and evaluated patients’ total body water levels, 24-hour blood pressure, and left ventricular mass.
They found that skin sodium content was associated with systolic blood pressure, whereas total body water was not. They also found that skin sodium content was more strongly associated with left ventricular mass than total body water.
Moreover, the team found that skin sodium content explains left ventricular mass, and this was not affected by patients’ blood pressure or total body water.
“We believe that skin sodium reflects deposition of excess sodium,” Schneider said, according to a news release. “Our finding of a strong relationship between skin sodium and changes in the structure of the heart suggests that interventions that reduce skin sodium content — for example, dietary sodium restriction or medications that lead to increased sodium excretion — may have beneficial effects on the heart in patients with kidney disease.”