Mediterranean diet on a salt restriction background in adults with high normal blood pressure or grade 1 hypertension: A randomized controlled trial

BACKGROUND & AIMS

Non-pharmacological measures are recommended as the first-line treatment for individuals with high-normal blood pressure (BP) or mild hypertension. Studies directly comparing the BP effects of the Dietary Approaches to Stop Hypertension (DASH) vs. the Mediterranean diet (MedDiet) on a salt restriction background are currently lacking. Thus, our purpose was to assess the BP effects of a 3-month intensive dietary intervention implementing salt restriction either alone or in the context of the DASH, and the MedDiet compared to no/minimal intervention in adults with high normal BP or grade 1 hypertension.

METHODS

We randomly assigned never drug-treated individuals to a control group (CG, n = 60), a salt restriction group (SRG, n = 60), a DASH diet with salt restriction group (DDG, n = 60), or a MedDiet with salt restriction group (MDG, n = 60). The primary outcome was the attained office systolic BP difference among the randomized arms during follow-up.

RESULTS

A total of 240 patients were enrolled, while 204 (85%) completed the study. According to the intention-to-treat analysis, compared to the CG, office and 24 h ambulatory systolic and diastolic BP were reduced in all intervention groups. A greater reduction in the mean office systolic BP was observed in the MDG compared to all other study groups (MDG vs. CG: mean difference = -15.1 mmHg; MDG vs. SRG: mean difference = -7.5 mmHg, and MDG vs. DDG: mean difference = -3.2 mmHg, all P-values <0.001). The DDG and the MDG did not differ concerning the office diastolic BP and the 24 h ambulatory systolic and diastolic BP; however, both diets were more efficient in BP-lowering compared to the SRG.

CONCLUSIONS

On a background of salt restriction, the MedDiet was superior in office systolic BP-lowering, but the DASH and MedDiet reduced BP to an extent higher than salt restriction alone.

Efficacy of comprehensive group-based education in lowering body weight, uric acid levels, and diuretic use in patients with chronic kidney disease: a retrospective study

BACKGROUND

Patient education for the management of chronic kidney disease (CKD) is attracting attention. Therefore, this study aimed to analyze changes in body weight, uric acid, and estimated-glomerular filtration rate (eGFR) in patients with CKD after a group-based education during admission.

METHODS

Overall, 157 patients with CKD, who were discharged from the nephrology department of our hospital between January 2015 and October 2019, received group-based education or individual-based education by nurses at admission. Deltas of body weight, uric acid, and eGFR, 6 months from baseline, were compared between group- and individual-based education using the Wilcoxon rank sum test.

RESULTS

In total, 60 patients receiving group-based education (G group, n =35) or individual-based education (I group, n =25) during admission were included in this retrospective study. The patient characteristics at baseline were as follows: age mean, 72 ± SD 9; 16 females and 44 males; body weight, 62 ± 17 kg; eGFR median, 21 (IQR: 14, 29) mL/min/1.73 m2; UA, 7 (6.1, 7.5) mg/dL; and estimated intake of salt 6.9 (6.2, 8.4) g/day. Delta eGFR (mL/min/1.73 m2) was -1 (-3, 3) for G group and -1 (-2.5, 2) for I group (p = 0.8039). Delta body weight (kg) was -0.4 (-1.6, 0) for G group and 0 (-0.45, 0.95) for I group (p = 0.0597). Delta uric acid (mg/dL) was -1.1 (-1.6, 0.1) for G group and -0.2 (-1.1, 0.5) for I group (p = 0.0567). In patients with higher sodium intake (≥ 117.4 mEq/day), delta body weight was significantly lower in the group-based education group than in the individual-based education group (p = 0.0398).

CONCLUSIONS

A comprehensive group-based education in patients with CKD may effectively suppress body weight and uric acid in 6 months along with less frequent diuretic use.

Nutritional management of heart failure

Nutrition in the cardiovascular field to date has focused on improving lifestyle-related diseases such as hypertension and diabetes from the viewpoint of secondary prevention. For these conditions, "nutrition for weight loss" is recommended, and nutritional guidance that restricts calories is provided. On the other hand, in symptomatic Stage C and D heart failure, it is known that underweight patients who manifest poor nutrition, sarcopenia, and cardiac cachexia have a poor prognosis. This is referred to as the "Obesity paradox". In order to "avoid weight loss" in patients with heart failure, a paradigm shift to nutritional management to prevent weight loss is needed. Rather than prescribing uniform recommendation for salt reduction of 6 g/day or less, awareness of the behavior change stage model is attracting attention. In this setting, the value of salt restriction will need to be determined to determine the priority level of intervention for undernutrition versus the need to prevent congestive signs and symptoms. In the Intensive Care Unit (ICU)/Cardiac Care Unit (CCU) for acute heart failure, nutritional intervention should be considered within 48 h of admission. Key points are selection of access route, timing of intervention, and monitoring of side effects. In nutritional management at home and in end-of-life care, food is a reflection of an individual's values, as well as a source of joy and encouragement. The importance of digestive tract should also be recognized in heart failure from oral flail to intestinal edema, constipation, and the intestinal bacteria called the heart-gut axis. Finally, we would like to propose a new term "heart nutrition" for nutritional management in patients with heart failure in this review. Compared to the evidence for exercise therapy in heart failure, studies assessing nutritional management remain scarce and there is a need for research in this area in the future.

Relationship between salt consumption and iodine intake in a pediatric population

Purpose

The World Health Organization recommends reduction of salt intake to < 5 g/day and the use of iodized salt to prevent iodine deficiency states. A high prevalence of excess salt consumption and an inadequate iodine intake has been previously shown in an Italian pediatric population. It was appropriate, therefore, to analyse in the same population the relationship occurring between salt consumption and iodine intake.

Methods

The study population was made of 1270 children and adolescents. Estimates of salt consumption and iodine intake were obtained by measuring 24 h urinary sodium and iodine excretion.

Results

The iodine intake increased gradually across quartiles of salt consumption independently of sex, age and body weight (p < 0.001). Median iodine intake met the European Food Safety Authority adequacy level only in teenagers in the highest quartile of salt consumption (salt intake > 10.2 g/day). We estimated that approximately 65–73% of the total iodine intake was derived from food and 27–35% from iodized salt and that iodized salt made actually only 20% of the total salt intake.

Conclusion

In this pediatric population, in face of an elevated average salt consumption, the use of iodized salt was still insufficient to ensure an adequate iodine intake, in particular among teenagers. In the perspective of a progressive reduction of total salt intake, the health institutions should continue to support iodoprophylaxis, in the context of the national strategies for salt reduction. In order for these policies to be successful, in addition to educational campaigns, it is needed that the prescriptions contained in the current legislation on iodoprophylaxis are made compelling through specific enforcement measures for all the involved stakeholders.

Electronic supplementary material

The online version of this article (10.1007/s00394-020-02407-w) contains supplementary material, which is available to authorized users.

Dashing away hypertension: Evaluating the efficacy of the dietary approaches to stop hypertension diet in controlling high blood pressure

The dietary approaches to stop hypertension (DASH) diet has been developed and popularized as a non-pharmaceutical intervention for high blood pressure reduction since 1995. However, to date, a comprehensive description of the biochemical rationale behind the diet’s principal guidelines has yet to be compiled. With rising interest for healthy and reliable life-style modifications to combat cardiovascular disease, this review aims to compile the most recent and relevant studies on this topic and make an informed assessment as to the efficacy of and underlying mechanisms operant in the DASH diet. Specifically, the merits of lowering dietary intake of sodium and saturated fat, as well as increasing the intake of fruits, vegetables, fiber, and dairy, have been shown to attenuate hypertension individually. Upon review of this evidence, we conclude that the combination of dietary patterns proposed in the DASH diet is effective in attenuating high blood pressure. We also suggest that efforts to more widely implement adoption of the DASH diet would be beneficial to public health.

Factors affecting the progression of renal dysfunction and the importance of salt restriction in patients with type 2 diabetic kidney disease

BACKGROUND

Type 2 diabetic kidney disease (DKD) is the most common cause of end-stage renal failure, and the prevention of its progression has been a topic of discussion.

METHODS

Sixty type 2 DKD patients were retrospectively evaluated for 1 year. Factors independently affecting the annual Ccr decline were examined by multivariable linear regression analysis. Patients were further divided into 2 groups based on their degree of renal function, and between-group differences at study initiation were evaluated.

RESULTS

Ccr values were 21.0 ± 11.8 mL/min/1.73 m(2) at study initiation, and 15.7 ± 10.9 mL/min/1.73 m(2) after 1 year of observation. The multivariable linear regression analysis indicated salt intake (standardized coefficient: -0.34, P = 0.010) and urinary protein excretion (standardized coefficient: -0.33, P = 0.011) to be factors independently affecting the annual Ccr decline. Although decliners (-9.8 ± 4.7 mL/min/1.73 m(2)/year) had a significantly higher salt intake than non-decliners (-1.1 ± 3.8 mL/min/1.73 m(2)/year) at study initiation, this difference disappeared at the end of the study as a result of intensive dietary education. In 21 decliners with an additional year of follow-up, the annual Ccr decline significantly improved from -10.1 ± 5.3 to -5.3 ± 7.4 mL/min/1.73 m(2)/year (P = 0.02).

CONCLUSION

Salt intake and urinary protein excretion were associated with annual Ccr decline in type 2 DKD patients. Furthermore, dietary education covering salt intake may have positively affected the change in Ccr.

Intravenous salt supplementation with low-dose furosemide for treatment of acute decompensated heart failure

BACKGROUND

Theoretically, salt supplementation should promote diuresis through increasing the glomerular filtration rate (GFR) during treatment of acute decompensated heart failure (ADHF) even with low-dose furosemide; however, there is little evidence to support this idea.

METHODS AND RESULTS

This was a prospective, randomized, open-label, controlled trial that compared the diuretic effectiveness of salt infusion with that of glucose infusion supplemented with low-dose furosemide in 44 consecutive patients with ADHF. Patients were randomly administered 1.7% hypertonic saline solution supplemented with 40 mg furosemide (salt infusion group) or glucose supplemented with 40 mg furosemide (glucose infusion group). Our major end points were 24-hour urinary volume and GFR. Urinary volume was greater in the salt infusion group than in the glucose infusion group (2,701 ± 920 vs 1,777 ± 797 mL; P < .001). There was no significant difference in the estimated GFR at baseline. Creatinine clearance for 24 h was greater in the salt infusion group than in the glucose infusion group (63.5 ± 52.6 vs 39.0 ± 26.3 mL min(-1) 1.73 m(-2); P = .048).

CONCLUSIONS

Salt supplementation rather than salt restriction evoked favorable diuresis through increasing GFR. The findings support an efficacious novel approach of the treatment of ADHF.