Estimation of dietary salt intake from 24-hour and on spot urinary sodium excretion in Bangladesh.

Excessive salt intake is one of the main risk factors of hypertension. In Bangladesh, it is a significant contributor to the increased risk of non-communicable diseases. The study was conducted in 2012-2013 to estimate the salt consumption status and assess the relationship between excessive salt intake and high blood pressure among the middle-aged urban and rural Bangladeshi populations. Age, BMI, and blood pressure of the respondents were taken and expressed as Mean and SD or 95% CI. History of hypertension of the respondents and information regarding dietary salt intake patterns was gathered among the subjects by residence and expressed as frequency & percentage. Some urinary parameters like urinary sodium, potassium, creatinine, the ratio of sodium and potassium, and the urine volume were assessed among respondents by residence. The population salt consumption was estimated from both methods of 24-hour urinary sodium concentration and spot urine concentration like Tanaka, Kawasaki, and INTERSALT methods. Correlation between estimated salt intake by 24-hour urine and three spot urine methods were measured. Estimated consumed salt was measured by gram/day. Correlations between systolic and diastolic blood pressures and urinary parameters such as sodium (gm/day), Potassium (gm/day), and the ratio of Sodium and Potassium (mmol/L / mmol/L) were calculated. Salt intake from 24-hour urine and ratio of sodium and potassium excretion were divided into four quartiles to observe differences in blood pressure between quartiles. Multilinear regression was applied to observe correlations between blood pressure and salt intake estimated from 24-hour urine and ratio of Na: K excretion after adjusting for age and BMI. Here it is noted that the ratio of urinary Na: K excretion was positively correlated with both the systolic and diastolic blood pressure even after adjustment by age and BMI in multilinear regression. For this study, all analysis was done by using SPSS version 26.0, and the significance level was considered at a 95% confidence interval.