Urinary and dietary sodium to potassium ratio as a useful marker for estimating blood pressure among older women in Indonesian Urban coastal areas

BACKGROUND: Risk factors for hypertension (HT) are age, high sodium (Na) intake, and low potassium (K) intake, as well as the geographical location of a region such us coastal area. Calculation of the sodium-to-potassium (Na/K) ratio was more∼strongly associated with blood pressure (BP) than either Na or K alone. Dietary recalls and urine analyses are the most feasible methods for estimating electrolyte intake. OBJECTIVE: This study aims to analyze the association between both urinary and dietary (Na/K) ratio and BP among older women residing at urban coastal in Indonesia. METHODS: The cross-sectional study involved 51 older women aged ≥45 y post menopause in urban coastal dwellers. A single 24-h urine collection and food recall 2×24 h were used to assess sodium and potassium intake. RESULTS: Of the 51 subjects mean age 56.98±5.7 years completed the study, 37.3% of subjects were classified as hypertensive. The mean of urinary and dietary Na/K ratio were 5.28±1.68 and 1.12±0.74 respectively. Urinary Na/K ratio was independently associated with systolic BP (SBP), meanwhile, the association between dietary Na/K ratio and both SBP and diastolic BP (DBP) showed significant correlation only in the unadjusted model. CONCLUSION: Na/K ratio is a useful marker for estimating SBP and assessing populations at high risk for HT. The slightly low Na and substantially low K intake might cause the Na/K ratio become high enough to induce HT. Since the prevalence of HT is high enough, studies in this field may provide clues for the further understanding of its causes and get effectively ways to decrease Na/K ratio in urban coastal dwellers.