Emilio Rodrigo, MD, PhD, and colleagues at Hospital Marqués de Valdecilla in Santander, Spain, studied 397 recipients of deceased-donor kidneys who had a mean follow-up of seven years. They estimated subjects’ sodium intake by urinary sodium excretion on 24-hour urine collections one year after transplantation. Compared with patients in the lowest tertile of sodium intake, those in the highest tertile had a significantly higher percentage of patients with hypertension (89.5% vs. 81.1%) and were on a greater number of antihypertensive drugs (1.60 vs. 1.32).
In addition, the investigators found that a systolic blood pressure of 160 mm Hg or higher was associated with a nearly twofold increased likelihood of death-censored graft loss, independent of recipient age, acute rejection, and serum creatinine level at one year.
Of the 397 patients, 341 (85.9%) exceeded the World Health Organization recommended target of less than 5 g/day. The researchers reported that diminishing salt intake to less than 5 g/day can help to reduce systolic BP by about 2.4 mm Hg.
“Applying salt restriction to kidney transplant recipients can help to control blood pressure and perhaps improve graft survival,” the authors concluded.