Effect of Salt Intake on Plasma and Urinary Uric Acid Levels in Chinese Adults: An Interventional Trial

Abstract

Uric acid (UA) has been proposed as an important risk factor for cardiovascular and renal morbidity. We conducted an interventional trial to assess effects of altered salt intake on plasma and urine UA levels and the relationship between UA levels and salt sensitivity in humans. Ninety subjects (18–65 years old) were sequentially maintained on a normal diet for 3 days at baseline, a low-salt diet for 7 days (3.0 g/day, NaCl), and a high-salt diet for an additional 7 days (18.0 g/day of NaCl). Plasma UA levels significantly increased from baseline to low-salt diet and decreased from low-salt to high-salt diet. By contrast, daily urinary levels of UA significantly decreased from baseline to low-salt diet and increased from low-salt to high-salt diet. The 24 h urinary sodium excretions showed inverse correlation with plasma UA and positive correlation with urinary UA excretions. Additionally, salt-sensitive subjects presented significantly higher plasma UA changes in comparison to salt-resistant subjects, and a negative correlation was observed between degree of salt sensitivity and plasma UA difference. The present study indicates that variations in dietary salt intake affect plasma and urine UA levels, and plasma UA may be involved in pathophysiological process of salt sensitivity.

Association between urinary sodium excretion and uric acid, and its interaction on the risk of prehypertension among Chinese young adults

“…Thus, it is possible that decreased renal reabsorption of sodium from excess sodium intake contributes to a decrease in urate reabsorption. This hypothesis has been evidenced by our interventional study showing that urinary UA excretions were markedly increased during high-salt intake, which was further reinforced by the observation that urinary UA positively correlated with urinary sodium excretion 37 . Furthermore, a Spanish study also found a directly correlation between the clearance of UA and fractional excretion of sodium, indicating the potential interaction of sodium and UA excretion 38 .…”

Dietary pattern analysis among stone formers: resemblance to a DASH-style diet

“…The reduction of oxalate excretion by decreasing sodium intake has been previously ascribed to a reduction in intestinal oxalate absorption 38 . More recently, it has been shown that urinary uric acid was significantly decreased by a low-salt diet 39 .…”

Uric acid and the cardio‐renal effects of SGLT2 inhibitors

“…46 notably higher carotid-femoral and carotid-radial pulse wave velocities and impaired flow-mediated vasodilation. [57][58][59][60][61] However, the extent to which excess uric acid might contribute to these effects is unclear. [57][58][59][60][61] However, the extent to which excess uric acid might contribute to these effects is unclear.…”

“…55,56 Hyperuricaemic hypertension is also typically associated with increased activity of the reninangiotensin-aldosterone system (RAAS), including increased plasma renin activity and increased aldosterone secretion, and hyperuricaemia has been linked with increased salt-sensitivity in some individuals. [57][58][59][60][61] However, the extent to which excess uric acid might contribute to these effects is unclear. 62…”