|EVIDENCE-BASED MEDICINE: SUMMARY OF STUDY
|Year : 2016 | Volume
| Issue : 4 | Page : 126-127
Is low sodium intake beneficial?
Assistant Professor, Department of Biochemistry, Christian Medical College, Vellore, Tamil Nadu, India
|Date of Web Publication||22-Nov-2016|
Source of Support: Associations of urinary sodium excretion with cardiovascular events in individuals with or without hypertension: A pooled analysis of data from four studies. Mente A et al. Lancet. 2016 Jul 30;388(10043):465.75., Conflict of Interest: None
|How to cite this article:|
Anand R. Is low sodium intake beneficial?. Curr Med Issues 2016;14:126-7
Clinical Question: Is the association between sodium intake and incidence of cardiovascular events different between individuals with and without hypertension?
- High dietary sodium intake increases risk of cardiovascular disease in hypertensive subjects
- Low dietary sodium can increase risk of cardiovascular events in subjects irrespective of their hypertensive status
- Dietary recommendation for reducing sodium intake is best targeted at populations with hypertension who consume high sodium diets.
| Background|| |
Several studies in the past have observed an association between dietary sodium (Na) intake and risk of cardiovascular disease (CVD) events and mortality. ,,, Interestingly, an increased risk of CVD is noted with both low and high Na intake states depicting a U-shaped profile. However, whether these observed associations are different between those with hypertension or without hypertension are not known.
| Methods|| |
Investigators of the present study recruited individuals who were part of four different cohorts, namely, PURE, DREAM, ONTARGET, and TRANSCEND. ,,, This included 133,118 individuals from 49 different countries. Among the study participants, 63,559 were hypertensives (HT Group) and 69,559 were without hypertension (non-HT Group). The study aimed at correlating dietary Na intake with the risk of cardiovascular events as their primary objective.
Since, an accurate, direct quantification of dietary Na intake is difficult, the researchers used an indirect approach. A morning fasting urine specimen was collected from all participants for estimation of spot Na. From the obtained value, a 24 h urine Na excretion was calculated using Kawasaki et al. formula.  This was used a surrogate marker for dietary Na intake. The 24 h urine excretion was correlated with the incidence of CVD events over 4 years.
| Results|| |
The findings could be summarized in [Table 1]:
Financial support and sponsorship
- For each g change in intake of Na, the rise in systolic blood pressure was 2.08 mmHg in the HT group, while the rise was 1.22 mmHg in non-HT Group (P < 0.0001)
- In the HT Group, it was noted that high Na intake (>7 g/day) was associated with an increased risk of CVD in HT Group with a hazard ratio (HR) of 1·23 (95% confidence interval [CI] 1·11-1.37). On the other hand, low Na intake (<3 g/day) was also associated with an increased risk of CVD (HR 1·34 (95% CI 1·23-1·47)
- In the non-HT group, high Na intake was not associated with increased risk of CVD while low Na intake significantly increased the risk (HR 1·26 (95% CI 1·10-1·45)
- In both groups, moderate Na intake had no association with risk of CVD.
Conflicts of interest
There are no conflicts of interest.
| References|| |
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