People who habitually add salt to their meals at the table may unknowingly be risking their kidneys, according to a study utilizing UK Biobank data. Chronic salt additions are associated with an elevated risk of developing chronic kidney disease (CKD), as revealed by researchers led by Rui Tang, a doctoral candidate in epidemiology at Tulane University in New Orleans, Louisiana. The study was published in JAMA Network Open.
Large Study Sample
In a population-based cohort study comprising over 460,000 UK Biobank participants aged 37-73 years, Tang and colleagues explored the association between adding table salt to food and increased CKD risk.
Participants indicated how often they added salt to their meals: Never or rarely, sometimes, often, or always. The follow-up period exceeded a decade, and median duration was 11.8 years. During this time, approximately 22,000 new CKD cases were documented. Data analysis revealed a significantly higher CKD risk among those who frequently added salt.
The extent of risk elevation varied with the frequency of salt additions. Even occasional salters had a 7% higher risk than those who never or rarely added salt. For frequent salters, the risk increased by 12%, and for those who always added salt, it rose to 29%. These results were adjusted for age and gender.
Worse Overall Health
The research group noted that individuals who frequently added salt were generally less healthy, adopting an unhealthier lifestyle and having lower socioeconomic status. They exhibited higher body mass index (BMI), were more likely to smoke, had diabetes or cardiovascular diseases, and had reduced estimated glomerular filtration rate (eGFR) at the beginning of the study. Moreover, their Townsend Deprivation Index, indicating material deprivation, was higher.
Considering these factors, the researchers adjusted the results not only for age and gender but also for ethnicity, Townsend Deprivation Index, eGFR, BMI, smoking status, alcohol consumption, physical activity, elevated cholesterol levels, diabetes, cardiovascular diseases, hypertension, infectious diseases, immune system disorders, and the use of nephrotoxic medications.
Association Persists
Even after accounting for these factors, a significant, albeit attenuated, association between salt additions and CKD risk remained. The risk increased by 2% for occasional salters, 5% for frequent salters, and 6% for those who always added salt.
The research group led by Tang concluded that adding salt to meals could be associated with an increased risk for CKD in the general population. However, they highlighted several limitations that should be considered when interpreting the study results.
Reducing Salt
Primarily, self-reported frequency of salt addition doesn't precisely reflect actual salt consumption. While earlier studies validated the accuracy of this variable, the researchers acknowledged the possibility that frequent salt addition may merely be a marker for an unhealthy lifestyle.
Nevertheless, the authors speculated that reducing the frequency of salt additions to meals could contribute to lowering CKD risk in the general population. They suggested validating their results in post hoc analyses or follow-up studies from clinical trials.
This article was translated from the Medscape German edition.
Individuals who regularly sprinkle salt on their meals at the table may unwittingly jeopardize their kidney health, according to a study utilizing data from the UK Biobank. Researchers, led by Rui Tang, a doctoral candidate in epidemiology at Tulane University in New Orleans, found that habitual salt additions are linked to an increased risk of developing chronic kidney disease (CKD). The study, published in JAMA Network Open, involved a large-scale population-based cohort study with over 460,000 UK Biobank participants aged 37-73.
During the follow-up period of over a decade, with a median duration of 11.8 years, approximately 22,000 new CKD cases were recorded. Participants were categorized based on how often they added salt to their meals: Never or rarely, sometimes, often, or always. The analysis revealed a notable elevation in CKD risk for those who frequently added salt. Even occasional salt users had a 7% higher risk compared to those who seldom added salt, while frequent salt users faced a 12% increased risk. For those who always added salt, the risk rose to 29%. These findings were adjusted for age and gender.
The study also observed that individuals who frequently added salt tended to have poorer overall health, engaging in unhealthy behaviors and possessing a lower socioeconomic status. They exhibited higher body mass index (BMI), were more likely to smoke, had diabetes or cardiovascular diseases, and showed reduced estimated glomerular filtration rate (eGFR) at the study's commencement. Despite adjusting for various factors, including ethnicity, socioeconomic status, BMI, and health-related behaviors, a significant albeit attenuated association between salt additions and CKD risk persisted.
The research team, led by Tang, concluded that adding salt to meals could be linked to an increased risk of CKD in the general population. However, they acknowledged certain limitations in the study, such as the reliance on self-reported salt addition frequency, which may not precisely reflect actual salt consumption. Despite these limitations, the authors suggested that reducing the frequency of salt additions might contribute to lowering CKD risk and proposed further validation through post hoc analyses or follow-up studies from clinical trials.
No comments yet