Association between 24-h urinary sodium to potassium ratio and mild cognitive impairment in community-based general population

Objective: To explore the relationship between parameters of Na and K excretion using 24-h urine sample and mild cognitive impairment (MCI) in general population. Design: This is a cross-sectional study. Setting: Community-based general population in Emin China. Participants: Totally, 1147 subjects aged >= 18 years were selected to complete the study, with a multistage proportional random sampling method. Cognitive status was assessed with Mini Mental State Examination (MMSE) questionnaire and timed 24-h urine specimens were collected. Finally, 561 participants aged >= 35 years with complete urine sample and MMSE data were included for the current analysis and divided into groups by tertiles of 24-h urinary sodium to potassium ratio (24-h UNa/K) as lowest (T1), middle (T2) and highest (T3) groups. Results: The MMSE score was significantly lower in T3, compared with the T1 group (26 center dot 0 v. 25 center dot 0, P = 0 center dot 002), and the prevalent MCI was significantly higher in T3 than in T1 group (11 center dot 7 % v. 25 center dot 8 %, P < 0 center dot 001). In multiple linear regression, 24-UNa/K (beta: -0 center dot 184, 95 % CI -0 center dot 319, -0 center dot 050, P = 0 center dot 007) was negatively associated with MMSE score. In multivariable logistic regression, compared with T1 group, 24-h UNa/K in the T2 and T3 groups showed 2 center dot 01 (95 % CI 1 center dot 03, 3 center dot 93, P = 0 center dot 041) and 3 center dot 38 (95 % CI 1 center dot 77, 6 center dot 44, P < 0 center dot 001) fold odds for presence of MCI, even after adjustment for confounders. More augmented results were demonstrated in sensitivity analysis by excluding individuals taking anti-hypertensive agents. Conclusions: Higher 24-h UNa/K is in an independent association with prevalent MCI.

Automated summary

The study explored the relationship between parameters of Na and K excretion using 24-h urine sample and mild cognitive impairment (MCI) in the general population. The results showed that higher 24-h UNa/K ratio was independently associated with prevalent MCI, even after adjusting for confounders. This suggests a potential link between sodium-potassium balance and cognitive function in older adults.