The impact of daily sodium intake on posttransplant hypertension in kidney allograft recipients

Abstract

Introduction: Posttransplant hypertension is a well-known risk factor for long-term allograft failure and mortality in kidney recipients. Although dietary sodium restriction is a widely recommended nonpharmacological measure for control of blood pressure (BP), no detailed investigation has been conducted regarding the impact of dietary sodium restriction on this condition.

Methods: Thirty-two patients on antihypertensive treatment completed the study. They were randomly divided into two groups: controls (group 1) versus strict sodium diet (group 2; 80 to 100 mmol sodium daily). After randomization, 24-hour urine for sodium measurement, BP, and allograft functions were recorded at baseline and after 3 months. BP treatment was reevaluated at each visit throughout the study.

Results: At baseline, there was no significant difference in age, sex, serum creatinine, systolic and diastolic BP, antihypertensive drugs, or 24-hour urinary sodium levels between the groups. After 3 months, daily urinary sodium excretion (from 190+/-75 to 106+/-48 mEq/d, P<.0001), systolic BP (from 146+/-21 to 116+/-11 mm Hg), and diastolic BP (from 89+/-8 to 72+/-10 mm Hg) had significantly decreased in group 2, while no significant changes were observed in group 1.

Conclusion: Low sodium intake in combination with antihypertensive treatment appears to efficiently control BP in kidney allograft recipients with hypertension. Twenty-four-hour urinary sodium excretion should be checked regularly in these patients as a useful marker to indicate whether the patient complies with low sodium intake.