Association Between Adding Salt to Food, CKD Risk

It is unknown whether a higher salt intake is associated with CKD, so researchers led by Rui Tang, MS, MPH, investigated the association of self-reported frequency of adding salt to foods with incident CKD risk in a general adult population. Participants self-reported their frequency of adding salt to foods as never or rarely, sometimes, usually, or always. 

The population-based study included UK Biobank participants aged 37 to 73 years who did not have CKD at baseline. There were 465,288 individuals in the cohort; 255,102 (54.83%) were female and 210,186 (45.17%) were male. Mean age was 56.32 (SD 8.08) years. 

A higher self-reported frequency of adding salt to foods was significantly associated with a higher CKD risk after adjusting for covariates. There were 2,231 incident events of CKD reported during a median (IQR) follow-up of 11.8 (1.4) years. Compared to those who reported never or rarely adding salt to foods, participants who reported sometimes adding salt to foods (adjusted HR [aHR], 1.04; 95% CI, 1.00-1.07), those who reported usually adding salt to foods (aHR, 1.07; 95% CI, 1.02-1.11), and those who reported always adding salt to foods (aHR, 1.11; 95% CI, 1.05-1.18) had an increased risk of CKD (P<.001). Participants who self-reported a higher frequency of adding salt to foods were also more likely to smoke, have diabetes or cardiovascular disease (CVD) at baseline, have a higher body mass index (BMI), have a higher Townsend Deprivation Index score, and have a weakened baseline eGFR compared to those who reported less frequently adding salt to foods.  

The results indicate that reducing the frequency of adding salt to foods could provide a strategy for lowering CKD risk in the general population. 

Source: JAMA Network Open