SEASONAL CHANGES in salt intake among patients with chronic kidney disease (CKD) may influence blood pressure differently in men and women, with a particularly strong effect observed in men during summer, according to a new study.
Researchers followed 168 CKD patients over the course of a year, analysing detailed daily urine collections to estimate salt intake alongside clinical measurements. Of these, 147 patients had complete data for both summer and winter, enabling a direct comparison of seasonal variation within the same individuals, a key strength given the limited evidence in this area to date.
Seasonal Patterns in Salt Intake and Blood Pressure
Consistent with previous knowledge, blood pressure (BP) was generally higher in winter than in summer. However, the study also found that salt intake followed a similar seasonal pattern, increasing during winter months. Among male participants, winter was associated with higher body weight, body mass index (BMI), BP, and levels of certain blood markers including low-density lipoprotein (LDL) cholesterol and cholinesterase. In contrast, female participants showed more limited seasonal changes, with increases observed in BP and select biochemical markers, but not in salt intake.
The most notable finding emerged from regression analyses examining the relationship between salt intake and systolic BP. In men, a significant positive correlation was identified, with higher salt intake linked to higher systolic BP. Interestingly, this association was strongest during the summer, despite overall salt consumption being lower than in winter. No such correlation was observed in women in either season.
To account for potential confounding effects of medications, the researchers conducted a subgroup analysis of 90 patients not taking drugs that affect sodium excretion. The results remained consistent, reinforcing the robustness of the findings.
Implications for Personalised CKD Management
The authors suggest that these sex-specific differences could have implications for personalised dietary and hypertension management strategies in CKD patients. In particular, the heightened sensitivity of systolic BP to salt intake in men during summer highlights a potential window for targeted intervention. Further research is needed to understand the underlying mechanisms and to explore whether similar patterns exist in broader populations.
Reference
Ohashi N et al. Seasonal variation of salt intake in patients with chronic kidney disease correlates with that of systolic blood pressure in males in summer. Clin Exp Nephrol. DOI: 10.1007/s10157-026-02871-4.
Featured image: Maurice Yom on Adobe Stock
