Objective: Sodium retention causes posttransplant hypertension, and sodium restriction is recommended in kidney transplantation recipients. We investigated the changes in salt intake and age-specific differences in salt intake over the posttransplant periods, and considered what are important to provide the guidance for salt reduction tailored to individual recipients. We also investigated the differences in blood pressure levels depending on the differences in the levels of salt intake.
Methods: We calculated salt intake for 38 recipients who underwent kidney transplantation from August 2013 to August 2018 using Tanaka’s equation, and also extracted their blood pressure levels.
Results: The rate of achieving the desired level of salt intake (less than 6 g a day) was 7.9％. Average salt intake was 7.8±1.4ｇ. Average BP(Systolic BP / Diastolic BP) by salt intake was, less than 6 g a day: 109 /71mmHg, 6g or over less than7g: 127 / 84mmHg, 7g or over less than 8g: 124 / 79mmHg, 8 g or over less than 9 g: 130 / 73mmHg, salt intake 9 or over less than 10 g: 133 / 83mmHg: salt intake over 10g: 137 / 81mmHg.
Discussion: The rate of achieving the desired level of salt intake (less than 6 g a day) was lower than expected, suggesting the need for reexamining the methods and contents of guidance. The awareness for salt restriction diminishes as the time passes after transplantations, leading to increased salt uptake; therefore, regular guidance for keeping salt intake low is necessary for the patients to be able to maintain the awareness for salt restriction. The guidance needs to consider the possibility that the taste sensitivity decreases with age. In addition, the recipients with higher salt intake had higher blood pressure, suggesting the need for the management of salt reduction.