Dietary Sodium-Potassium Ratio in Low-Sodium Diet Population and Its Association with Stroke: Insights from NHANES Database.

OBJECTIVE: To delve into the potential association between the dietary sodium-potassium ratio and stroke in the low-sodium diet population. METHODS: Cross-sectional analysis was done utilizing data from the National Health and Nutrition Examination Survey (NHANES) spanning 7 cycles from 2003 to 2016. 7141 samples were selected. Participants were categorized into stroke and non-stroke groups following population characteristics, and the association between dietary sodium-potassium ratio and stroke was analyzed across various categorical variables. Stratification of the dietary sodium-potassium ratio was done using quartiles. Weighted logistic regression models were constructed by adjusting various confounders to examine the sodium-potassium ratio's relationship with stroke. ubgroup analyses stratified by BMI were performed; interaction terms were evaluated with significance threshold p < 0.1. The relation between the sodium-potassium ratio and stroke risk was explored by Restricted Cubic Splines (RCS). RESULTS: Among the 7,141 participants with a dietary sodium intake ≤ 2,300 mg, the dietary sodium-to-potassium ratio was significantly higher in those who had experienced a stroke (ratio = 1.19 (0.51)) compared to those who had not (ratio = 1.11 (0.52)) (p < 0.05). An increased sodium-to-potassium ratio was associated with a higher risk of stroke in the following subgroups: women (Odds Ratio (OR) = 1.31, 95% CI: 1.05-1.62, p = 0.013), individuals with a BMI of 25-30 kg/m² (OR = 2.02, 95% CI: 1.40-2.91, p < 0.001), those with a history of smoking (OR = 1.79, 95% CI: 1.20-2.67, p = 0.004), alcohol consumers (OR = 1.29, 95% CI: 1.00-1.67, p = 0.047), those without coronary heart disease (OR = 1.33, 95% CI: 1.10-1.62, p = 0.003) or diabetes (OR = 1.33, 95% CI: 1.08-1.63, p = 0.006), but with hypertension (OR = 1.28, 95% CI: 1.03-1.59, p = 0.022). Stratified analysis by BMI indicated that the association between the sodium-to-potassium ratio and stroke was strongest and most consistent among overweight individuals (BMI 25-30 kg/m²), with all ORs exceeding 2 and p < 0.001. Additionally, a U-shaped relationship was observed between the dietary sodium-to-potassium ratio and stroke risk. A ratio within the range of 0.46-1.00 was associated with a reduced risk of stroke, with the lowest risk observed at a ratio of 0.76. CONCLUSION: In low-sodium diet population, association between dietary sodium-potassium ratio and stroke risk follows a "U" shaped correlation. However, prospective investigations are warranted to provide additional evidence to support findings.