Hyponatremia in patients with chronic kidney disease

Hyponatremia is a common condition encountered in clinical practice. A number of studies have associated low serum sodium levels with increased mortality in various patient populations, such as hospitalized patients and patients with various comorbid conditions; recent studies have shown that individuals with chronic kidney disease also are afflicted by hyponatremia. However, few studies have focused on patients with hemodialysis. Evidence supporting the incidence and prevalence of hyponatremia, clinical characteristics and the association with patient outcomes with hemodialysis is limited. In the present review, we examined the physiology and pathophysiology of water and sodium balance with a special emphasis on changes occurring during end-stage renal disease. The outcomes in patients undergoing hemodialysis were associated with low serum sodium. We evaluated the associations between hyponatremia and mineral bone abnormalities and discussed the elevated incidence and prevalence of difficult clinical outcomes associated with hyponatremia. We also provided specific recommendations for hemodialysis treatment in hyponatremic patients.