A 12-year study presented at ESC Congress reported that more than 4,000 people suffer from risk of heart failure due to high salt intake
Estimation of individual salt intake is methodologically demanding and therefore suitable population-based cohorts are rare. The study examined link between salt intake and the development of heart failure. As a part of study, 24 hour sodium extraction was done, which is considered as the gold standard for salt intake estimation at individual level. This was a prospective follow-up study of 4630 randomly selected men and women aged 25 to 64 years at baseline who participated in the North Karelia Salt Study and the National FINRISK Study between 1979 and 2002 in Finland.
As a part of study, self-administered questionnaire on health behavior, measurements of weight, height and blood pressure, a venous blood sample for laboratory analysis, and 24 hour urine sample were collected. The study cohort was followed up for 12 years through computerized register linkage to National Health Records. Cases of incident heart failure were identified from the Causes of Death Register, the Hospital Discharge Register and drug reimbursement records. The association of salt intake in quintiles (<6.8g, 6.8-8.8g, 8.8-10.9g, 10.96-13.7g and >13.7g/day) and the risk of an incident new heart failure event was estimated.
During the follow-up, 121 men and women developed new heart failure. In an age, sex, study year and area adjusted model, hazard ratios in the 2nd, 3rd, 4th and 5th salt intake quintiles, compared to the 1st one, were: 0.83, 1.40, 1.70 and 2.10. After further adjustment for systolic blood pressure, serum total cholesterol level and body mass index the hazard ratios were: 1.13, 1.45, 1.56 and 1.75, respectively. However, study concluded that larger, pooled population cohorts are required to make more detailed estimations of the increased heart failure risk associated with salt consumption.