The September edition of the American Journal of Hypertension has an Interesting opening in a Commentary by Asayama, Stolarz-Skezypek, Persu and Staessen.
“Until recently, the salt debate remained dominated by a select group of highly vocal global leaders whose goal is to impose their views through an unbalanced interpretation of so-called compelling evidence.”
There are a number of papers in the issue aside from this commentary including:
Relationship Between Nutrition and Blood Pressure: A Cross-Sectional Analysis from the NutriNet-Santé Study, a French Web-based Cohort Study.
Helene Lelong, Pilar Galan, Emmanuelle Kesse-Guyot, Leopold Fezeu, Serge Hercberg, and
Hypertension is the most prevalent chronic disease worldwide. Lifestyle behaviors for its prevention and control are recommended within worldwide guidelines. Nevertheless, their combined relationship with blood pressure (BP) level, particularly in the general population, would need more investigations. Our aim in this study was to evaluate the relative impact of lifestyle and nutritional factors on BP level.
Cross-sectional analyses were performed using data from 8,670 volunteers from the NutriNet-Santé Study, an ongoing French web-based cohort study. Dietary intakes were assessed using three 24-hour records. Information on lifestyle factors was collected using questionnaires and 3 BP measurements following a standardized protocol. Age-adjusted associations and then multivariate associations between systolic BP (SBP) and lifestyle behaviors were estimated using multiple linear regressions.
SBP was higher in participants with elevated body mass indices (BMIs). Salt intake was positively associated with SBP in men but not in women. The negative relationship between consumption of fruits and vegetables and SBP was significant in both sexes. Alcohol intake was positively associated with SBP in both sexes; physical activity was not. The 5 parameters representing the well-accepted modifiable factors for hypertension reduction plus age and education level, accounted for 19.7% of the SBP variance in women and 12.8% in men. Considering their squared partial correlation coefficient, age and BMI were the most important parameters relating to SBP level. Salt intake was not associated with SBP in either sex after multiple adjustments.
BMI was the main contributory modifiable factor of BP level after multiple adjustments.
Systematic Review of Health Outcomes in Relation to Salt Intake Highlights the Widening Divide Between Guidelines and the Evidence
Kei Asayama, Katarzyna Stolarz-Skrzypek, Alexandre Persu and Jan A. Staessen
Until recently, the salt debate remained dominated by a select group of highly vocal global leaders whose goal is to impose their views through an unbalanced interpretation of so-called compelling evidence. Sailing against the tide, in this issue of the Journal, Graudal and colleagues published a comprehensive review of the literature1 that complied with the highest possible quality standards as proposed by the Meta-analysis of Observational Studies in Epidemiology group.2 Data from 23 cohort studies and 2 follow-up studies of randomized controlled trials (n = 274,683 participants) showed that the risks of all-cause mortality or cardiovascular disease were higher at low and high vs. usual sodium intake, congruent with a U-shaped association between health outcomes and salt intake.1 The hazard ratios of total mortality and cardiovascular disease for low vs. usual sodium intake were 1.10 (95% confidence interval (CI) = 1.01–1.22) and 1.11 (95% CI = 1.01–1.22), respectively. The corresponding hazard ratios for high vs. usual sodium exposure were 1.16 (95% CI = 1.03–1.30) and 1.12 (95% CI = 1.02–1.24).
Cardiovascular endpoints and 24-hour urinary sodium
Graudal et al.’s findings are in line with our cohort study in European populations published in 2011.3 Nearly 90% of the world’s populations have a mean usual sodium intake ranging from 115 to 215 mmol per day.4 This range nearly corresponds with the mean values of 24-hour urinary sodium excretion in the low (107 mmol) and high (260 mmol) thirds of the distribution in European populations.3 Moreover, Graudal et al. reported that in population-representative samples adjusted for multiple confounders the risk of all-cause mortality was higher at low vs. usual sodium intake but not at high vs. usual sodium intake, with hazard ratios of 1.16 (95% CI = 1.09–1.23) and 0.96 (95% CI = 0.84–1.10), respectively.
Compared With Usual Sodium Intake, Low- and Excessive-Sodium Diets Are Associated With Increased Mortality: A Meta-Analysis
Niels Graudal, Gesche Jürgens, Bo Baslund, and Michael H. Alderman