Higher sodium intake increases risk for CVD in patients with CKD

Patients with chronic kidney disease who also consume a higher sodium diet have an increased risk for CVD, according to data presented at the 53rd European Renal Association – European Dialysis and Transplant Association Congress.

Jiang He, MD, PhD, of the Tulane University School of Public Health and Tropical Medicine, New Orleans, and colleagues assessed the association between urinary sodium excretion and CVD events in 3,757 patients with chronic kidney disease (CKD) from the Chronic Renal Insufficiency Cohort Study. Patients were followed from May 2003 to March 2013 and were required to provide urine specimens at baseline and at the first two annual visits.

Jiang He

The patients were stratified into four groups by sodium excretion: — less than 2,894 mg/24 hours, 2,894 mg/24 hours to 3,649 mg/24 hours, 3,650 mg/24 hours to 4,547 mg/24 hours and at least 4,548 mg/24 hours. The primary endpoint was a composite of CVD events (congestive HF, MI and stroke). The findings were simultaneously published in JAMA.

High sodium, high risk

According to the results, there were 804 composite CVD events during a median 6.8 years of follow-up. The cumulative incidence of composite CVD was 18.4% in the lowest quartile of urinary sodium excretion, 16.5% in the second-lowest, 20.6% in the second-highest and 29.8% in the highest (log-rank P < .001). Even after adjusting for potential confounders, the highest quartile was associated with increased risk for composite CVD events (HR = 1.36; 95%, CI, 1.09-1.7), HF (HR = 1.34; 95% CI, 1.03-1.74) and stroke (HR = 1.81; 95% CI, 1.08-3.02).

“These findings, if confirmed by clinical trials, suggest that moderate sodium reduction among patients with CKD and high sodium intake may lower CVD risk,” He and colleagues wrote.

Call for awareness

In a related editorial, Neil R. Powe, MD, MPH, and Kirsten Bibbins-Domingo, PhD, MD, MAS, both of the department of medicine and Center for Vulnerable Populations at the University of California, San Francisco, and the Priscilla Chan and Mark Zuckerberg San Francisco General Hospital, wrote: “Primary care physicians may not always recognize CKD. Arguably, physicians inform all patients, particularly those with hypertension and diabetes, about the risks associated with excessive salt intake. However, the high rate of [CV] events among patients with CKD may require more concerted attention, including periodic review of salt intake during physician visits.

“This is a call for awareness of the results of this important study ... Recommendations for sodium intake among patients with CKD should be based on replication of these results and most of all experimental studies. It is time to launch representative, large-scale clinical trials of dietary interventions for persons with CKD,” they wrote. – by Tracey Romero

References:

Mills K, et al. Salt on the Table. Presented at: 53rd European Renal Association – European Dialysis and Transplant Association Congress; May 21-24, 2016; Vienna.

Mills KT, et al. JAMA. 2016;doi:10.1001/jama.2016.4447.

Powe NR, Bibbins-Domingo K. JAMA. 2016;doi:10.1001/jama.2016.5985.

Disclosure: Mills reports no relevant financial disclosures. Please see full study for a list of all other researchers’ relevant financial disclosures. Powe and Bibbins-Domingo report no relevant financial disclosures. Bibbins-Domingo reports serving as chair of the U.S. Preventive Services Task Force.