Se leggiamo quanto scrive il redattore capo dell'American Journal of Hypertension, il dott. Alderman:
Sodium intake and mortality in the NHANES II follow-up study.
Cohen HW, Hailpern SM, Fang J, Alderman MH.
Source
Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, NY 10461, USA. hicohen@aecom.yu.edu
Abstract
PURPOSE:
US Dietary Guidelines recommend a daily sodium intake <2300 mg, but evidence linking sodium intake to mortality outcomes is scant and inconsistent. To assess the association of sodium intake with cardiovascular disease (CVD) and all-cause mortality and the potential impact of dietary sodium intake <2300 mg, we examined data from the Second National Health and Nutrition Examination Survey (NHANES II).
METHODS:
Observational cohort study linking sodium, estimated by single 24-hour dietary recall and adjusted for calorie intake, in a community sample (n = 7154) representing 78.9 million non-institutionalized US adults (ages 30-74). Hazard ratios (HR) for CVD and all-cause mortality were calculated from multivariable adjusted Cox models accounting for the sampling design.
RESULTS:
Over mean 13.7 (range: 0.5-16.8) years follow-up, there were 1343 deaths (541 CVD). Sodium (adjusted for calories) and sodium/calorie ratio as continuous variables had independent inverse associations with CVD mortality (P = .03 and P = .008, respectively). Adjusted HR of CVD mortality for sodium <2300 mg was 1.37 (95% confidence interval [CI]: 1.03-1.81, P = .033), and 1.28 (95% CI: 1.10-1.50, P = .003) for all-cause mortality. Alternate sodium thresholds from 1900-2700 mg gave similar results. Results were consistent in the majority of subgroups examined, but no such associations were observed for those <55 years old, non-whites, or the obese.
CONCLUSION:
The inverse association of sodium to CVD mortality seen here raises questions regarding the likelihood of a survival advantage accompanying a lower sodium diet. These findings highlight the need for further study of the relation of dietary sodium to mortality outcomes.
Evidence relating dietary sodium to cardiovascular disease.
Alderman MH.
Source
Albert Einstein College of Medicine, Dept. of Epidemiology & Population Health, Bronx, New York 10461, USA. alderman@aecom.yu.edu
Abstract
The expectation that dietary sodium intake might influence cardiovascular disease occurrence has been based upon its impact on blood pressure (BP). Solid experimental data confirms the ability of large (75-100 mmols/24 hours) changes in dietary sodium to reduce pressure by, on average, mid-low single digits. However, there is substantial inter-individual variation in BP response. In addition, sodium restriction generates other, sometimes undesirable effects, including increased insulin resistance, activation of the renin-angiotensin system, and increased sympathetic nerve activity. The health effects of salt restriction are, therefore, the sum of these recognized, and probably other unrecognized, intermediate effects. Ideally, salt restriction would be tested in a randomized clinical trial. In its absence, there are 9 observational studies linking baseline sodium intake, estimated by either 24 hour urine or dietary intake, to morbidity and mortality. The results have been inconsistent. The only study in hypertensive patients, there was an inverse relation of sodium to cardiovascular outcome. In a Japanese study, stroke incidence was increased among males with the highest salt intake. Two studies found a direct relation of sodium intake to cardiovascular mortality in an obese minority of the group studied. Taken together, these results suggest, not surprisingly given the genetic, behavioral, and environmental variety of humankind, that heterogeneity best describes the relation of sodium intake to cardiovascular morbidity and mortality. In short, the available data provides no support for any universal recommendation of a particular level of dietary sodium.
Naturalmente l'attuale caporedattore dell'American Journal of Hypertension è un ciarlatano senza titoli ne esperienza e la monumentale letteratura di senso contrario ci seppellirà. Amen [
]