Study of low salt diet in hypertensive patients with chronic kidney disease

@#Introduction: The efficacy of blood pressure (BP) reduction with salt restriction in CKD subjects and its sustainability is not well established. Methods: We enrolled 75 hypertensive patients with CKD into one-month salt restricting diet. 24-hour urinary sodium and potassium was measured to verify their salt intake followed by 1½ year follow-up. Results: Their creatinine clearance was 43 ± standard deviation 33ml/min/1.73m2. Urinary Na excretion (24HUNa) was 173±129mmol/day, reducing to 148±81 by 31±6 day. Mean, systolic and diastolic BP (MBP, SBP, DBP) were reduced from 102±9 to 97±11 (p<0.001), 148±10 to 139±16 (p<0.001), 78±12 to 75±12 mmHg (p=0.012) respectively. Moderate correlations were shown between reductions in 24-hour urinary Na and MBP, SBP, DBP: r=0.366, 0.260, 0.365; p=0.001, 0.025, 0.001; whereas 24-hour urinary Na-K ratio showed mild correlation. Subjects have some tendency to drift back to previous Na intake profile in follow-up and thus repetitive education is necessary. In subanalysis, 34 subjects with baseline 24HUNa >150 mmol/day, benefited significantly with MBP, SBP, DBP reduction from 102±9 to 95±9 (p=0.001), 146±10 to 135±14 mmHg (p=0.001), 80±11 to 75±11 mmHg (p=0.002) in line with 24HUNa reduction from 253±154 to 163±87mmol/day (p=0.004) and urinary protein-creation ratio reduction from geometric mean of 95 to 65 g/mol. Thirty five subjects with 24HUNa reduction of >20mmol/day have significant reduction in MBP, SBP, DBP: -8 vs -2, -15 vs -4, -5 vs -2 mmHg (p=0.027, 0.006, 0.218) and urinary protein-creatinine ratio: -82 vs 2g/mol (p=0.030) compared to the other forty subjects. Conclusion: Quantification of 24-hour urinary Na helps in predicting potential antihypertensive effect with dietary salt reduction of CKD subjects. Salt restriction reduces BP especially in patients with estimated daily sodium intake of >150mmol/day. Reduction in sodium intake beyond 20mmol/day reduced both BP and proteinuria.

Estimating the urinary sodium excretion in patients with chronic kidney disease is not useful in monitoring the effects of a low-salt diet

BACKGROUND: Several epidemiologic studies have suggested that the urine sodium excretion (USE) can be estimated in lieu of performing 24-hour urine collection. However, this method has not been verified in patients with chronic kidney disease (CKD) or in an interventional study. The purpose of this study was to evaluate the usefulness of estimating USE in a prospective low-salt diet education cohort (ESPECIAL). METHODS: A new formula was developed on the basis of morning fasting urine samples from 228 CKD patients in the ESPECIAL cohort. This formula was compared to the previous four formulas in the prediction of 24-hour USE after treatment with olmesartan and low-salt diet education. RESULTS: Most previously reported formulas had low predictability of the measured USE based on the ESPECIAL cohort. Only the Tanaka formula showed a small but significant bias (9.8 mEq/day, P < 0.05) with a low correlation (r = 0.34). In contrast, a new formula showed improved bias (−0.1 mEq/day) and correlation (r = 0.569) at baseline. This formula demonstrated no significant bias (−1.2 mEq/day) with the same correlation (r = 0.571) after 8 weeks of treatment with olmesartan. Intensive low-salt diet education elicited a significant decrease in the measured USE. However, none of the formulas predicted this change in the measured urine sodium after diet adjustment. CONCLUSION: We developed a more reliable formula for estimating the USE in CKD patients. Although estimating USE is applicable in an interventional study, it may be unsuitable for estimating the change of individual sodium intake in a low-salt intervention study.

Patrones de excreción urinaria de Sodio en población adulta en muestras de orina espontánea / Urinary sodium excretion patterns in adult population in spot urine samples

Introducción: El presente estudio describe los patrones de natriuresis según las características clínicas y sociodemográficas en una población adulta de Asunción. Métodos: Estudio transversal tipo encuesta y toma de muestra de orina a personas que acudieron al Mercado de Abasto y al Policlínico Municipal durante los meses de junio-setiembre del 2014. Se estimó natriuria en muestras de orina espontánea a primera hora de la mañana y en ayunas. Se incluyeron sujetos de 18 a 65 años. Se compararon las medianas de los valores de natriuria en mmol/L, utilizándose el test U de Mann-Whitney para comparar las variables de dos categorías y Kruskal-Wallis para las que tienen más de dos categorías. Resultados: Se aplicó la encuesta y se tomó muestra de orina a 463 personas. El 69,5% (322) eran mujeres. La media de edad fue 50,5 años (DE: 14,2). El 26,6% (123) negó antecedentes patológicos. La mediana de natriuria global fue 97,5 mmol/L (RIC: 59,3­139,3). Los niveles de natriuria no presentaron diferencias por sexo. Las personas menores de 30 años, con bajo consumo de verduras y mayor consumo de frituras presentaron valores de natriuria altos y estadísticamente significativos. El grupo de sujetos sanos mostró mayor excreción de sodio que los que refirieron diabetes o hipertensión arterial. Conclusiones: La mayor excreción de sodio en orina observada se presenta en personas jóvenes, sin antecedentes patológicos y, al mismo tiempo son los que también presentan los peores hábitos alimenticios. Estos resultados muestran la necesidad de intervención en el ámbito de la salud pública a fin de prevenir la patología cardiovascular y renal del futuro.

Introduction: The present study describes natriuresis patterns according to clinical and sociodemographic characteristics in adult population of Asuncion. Methods: Cross-sectional study of convenience sampling to people who attended the Mercado de Abasto and the Municipal Polyclinic during June to September 2014. People from 18 to 65 years old were included. Sodium was estimated from urine samples of spot urine taken in the morning and fasting. Median values of natriuresis in mmol/L were compared using the test Mann-Whitney and Kruskal-Wallis. Results: 463 people participated. 69.5% (322) were women. The mean age was 50.5 years (SD 14.2). 26.6% (123) denied pathological medical history. The median overall natriuresis was 97.5 mmol/L (IQR: 59.3-139.3). Natriuresis levels did not differ by sex. High values with statistically significant were presented in people under 30 years old, with low consumption of vegetables and increased consumption of fried food. The group of healthy subjects showed increased sodium excretion than those who reported diabetes or high blood pressure. Conclusions: The increased natriuresis occurs in young people without having pathological medical history and also having the worst eating habits. Public health policies must focus at this level to prevent future cardiovascular and renal disease it is at this level where public health must intervene to prevent future cardiovascular and renal disease.

Salt intake of patients undergoing maintenance hemodialysis and their knowledge and behaviour / 现代临床护理

Objective To study the salt intake of patients undergoing maintenance hemodialysis and explore their knowledge and behaviour. Methods The patients undergoing maintenance hemodialysis were offered salt spoon and soy sauce cup. Their diaries on home meals for 3 consecutive days were collected to calculate their salt intake. Meanwhile, a one to one interview was done to evaluate the accuracy of patient′s diet diary and the knowledge and behavior of low salt diet and find out related factors of salt intake. Results The average salt intake was (6.49 ± 1.64)g/d. The average composition rate in the low salt diet knowledge in low salt diet behavior was 51.00% and 47.00% respectively. Age and education level were the influencing factors of salt intake. Conclusions The average salt intake is much higher than the standard for the patients undergoing maintenance hemodialysis. Their low salt diet knowledge is in the middle level and their low salt diet behavior is in the middle or lower level. The related factors include age and education among patients undergoing maintenance hemodialysis.

Effect Evaluation of Comprehensive Intervention with Low-salt Diet in Elderly Patients with High Blood Pressure / 昆明医科大学学报

Objective To investigate the role of the extended-care in improving the compliance with low-salt diet in elderly patients with hypertension.Methods We selected 100 cases of elderly patients with hypertension in hospital.The 100 cases were divided into control group (50 cases) and observation group (50 cases) randomly.Observation group was given comprehensive intervention in low-salt diet education and control group was given traditional low-salt diet education.Tow groups were divided into three stages (on the day of admission,seven days after admission,one month after discharge).We analyzed low-salt cognitive scores,low-salt behavioral scores and salt-intake/d comparably.Results On the day of admission,tow groups had no statistically significant difference (P＞0.05) in low-salt cognitive scores,low-salt behavioral scores and salt-intake/d;seven days after admission,tow groups had statistically significant difforence (P＜0.05) in low-salt cognitive scores,low-salt behavioral scores and salt-intake/d;one month after discharge,tow groups had statistically significant difference (P＜0.05) in low-salt cognitive scores,low-salt behavioral scores and salt-intake/d.Conclusion We use comprehensive intervention method to elderly patients with hypertension in low-salt diet education,through personalized low-salt diet education following evidence-based nursing,we can increase the compliance with low-salt diet in elderly patients with hypertension after discharge and improve blood pressure control effectively and to promote the image of the hospital and achieve the higher satisfaction from patients and families.

The Effects of Sasang Constitutional Diet for Essential Hypertension on Blood Pressure, Fat, and Serum Lipid: on the subjects with aerobic exercise and low salt diet at the same time / 간호학회지

PURPOSE: This study was conducted to evaluate the effects of SaSang constitutional diet for essential hypertension on blood pressure, fat, and serum lipid on the subjects with aerobic exercise and low salt diet at the same time. METHOD: A non-equivalent control group time-series design was used. For the experimental group, aerobic exercise and SaSang constitutional diet were taught by researcher at health center. Test for hypothesis was done by repeated measured ANOVA. RESULT: There was significant decrease in systolic, diastolic, and MAP between the experimental group and control group over three different times. There was significant decrease in body weight, BMI, and body composition over three different times. But, there was no significant difference between groups and interaction by groups or over time. There was significant decrease in T/G and cholesterol over three different times. But, there was no significant difference in T/G, HDL, LDL, and total cholesterol between groups and interaction by groups or over time. CONCLUSION: Findings indicate that this study will contribute to develop nursing strategies for the regulation of the blood pressure as a means of alternative- complementary nursing intervention.

Comparative Study of Gingival Changes in Cyclosporine-Induced Nephrotoxicity with Normal and Low Salt Diet / 대한치주과학회지

Cyclosporine A(CsA) is a widely used immunosuppressant for transplant patients and is also used for the treatment of a wide variety of systemic diseases with immunologic disorders. However, its use is frequently limited because of complications such as nephrotoxicity or gingival hyperplasia. Although several hypotheses have been postulated for CsA-induced gingival hyperplasia, i.e. various cytokine effects of inflammatory cells, existence of plaque or CsA itself, but its pathogenesis is still unclear. For experimental chronic CsA toxicity, salt depletion has been shown to increased susceptibility of rodents to the effects of CsA, and this maneuver facilitates production of arteriolopathy and interstitial fibrosis in kidney that mimic the changes found in human. The purpose of this study was to evaluate pathogenesis of CsA-induced gingival hyperplasia by comparing changes between CsA administration groups of normal standard diet and those of low salt diet group. Specific pathogen-free, 20 to 25 days old(120 to 150 g), male Fisher-344 rats(KIST, Korea), 120 to 150g of body weight, were assigned to four groups of six animals each after one week of adaptation period for powder food. Group 1 received olive oil(300microliter/g of diet) with normal standard diet(0.4% of sodium)(NSD). Group 2 received CsA(Cypol-N, Jonggundang, Korea; 300microgram/g of diet) with normal standard diet(NSD+CsA). Group 3 received same amount of olive oil with low salt diet(0.05 % of sodium, Teklad Premier, U.S.A.)(LSD). Group 4 received same dose of CsA with low salt diet(LSD+CsA). Rats were pair fed and were sacrificed after six weeks. Renal histologic lesions associated with CsA, consisted of cortical interstitial fibrosis, tubular atrophy and hyalinization of arterioles and the impairment of renal function including increase of serum creatinine and decrease of glomerular filtration rate was more severe in low salt diet group. These were proved as the results of activated of renin-angiotensin system in the kidney by low salt condition. Meanwhile the degree of gingival hyperplasia at incisor and molar tooth was less severe in low salt diet group compared with normal sodium diet group. Hyperplastic gingiva showed mild epithelial hyperplasia and expanded underlyng stroma which consisted of matrix increasement, capillary proliferation and dilatation. While the number and the activation of fibroblasts were increased, inflammatory cells were rare in the stroma. The immunohistochemistry for TGF-beta1 in the kidney and gingiva revealed stronger positive in LSD+CsA in kidney but in gingiva of NSD+CsA. These results suggested followings; Gingival hyperplasia can be developed without inflammatory cells infiltration and seemed not induced by CsA by itself. The major role for gingival hyperplasia by CsA would be the secondary effect of TGF-beta, which maybe upregulated by CsA administration. Low salt diet can attenuate this hyperplasia perhaps by decreasing the activation of TGF-beta.

The Effect of Angiotensin Converting Enzyme Inhibitor on Chronic Cyclosporine Nephropathyin Salt Depleted Rats

PURPOSE: Cyclosporine(CsA) is a potent immunosuppressant but the use of CsA is associated with various side effects, especially nephrotoxicity. In the kidney, salt depletion activates the renin-angiotensin-aldosteron(RAS) system and accentuates chronic CsA nephropathy. We postulate that angiotensin converting enzyme inhibitors(ACEI) can prevent chronic CsA nephropathy, since ACEI may inhibit this cascades. This study was aimed to assess the effect of ACEI on chronic cyclosporin nephropathy in salt depleted rats. METHODS: 36 Fischer-344 rats were divided into 6 groups. Group I received normal salt diet(NSD). Group II received a low salt diet(LSD). Group III received CsA with a NSD. Group IV received CsA with a LSD. Group V received NSD+CsA with ACEI. Group VI received LSD+CsA with ACEI. Rats were sacrificed after six weeks, and the glomerular filtration rate(GFR), serum sodium, potassium and whole blood cyclosporine levels were measured. Renal tissues were sampled for the observation of histological changes. RESULTS: No differences in blood CsA level and serum sodium were found between groups during the course of this experiment. Serum potassium in group VI was significantly increased compared with group IV and V(P<0.05). In groups treated with CsA only and in those where CsA was combined with ACEI, GFR was found to be significantly more decreased in LSD than NSD, and GFR in group V was significantly decreased in comparison with group III (P<0.05). Renal histologic lesions associated with CsA, which consisted of cortical interstitial fibrosis, tubular atrophy and hyalinization of arterioles, were more severe in the LSD group. But, no differences were observed between the groups treated with CsA and ACEI, and the groups treated with only CsA. CONCLUSION: Salt depletion associated with the activation of the RAS system accentuated chronic CsA nephrotoxicity, but, ACEI could not reduce the functional and morphological changes of salt depleted kidneys, in which nephropathy can be exacerbated in spite of the blocking of the angiotensin II pathway. Further studies are required to elucidate whether ACEI ameliorated the effect of salt-depleted CsA nephrotoxicity upon the effective renal blood flow.

Compliance with Low-Salt Diet and Related Factors in Essential Hypertension Patients / 성인간호학회지

The purpose of this study was to investigate the compliance with low-salt diet in essential hypertension patients, and to identify the related factors of compliance with low-salt diet. The subjects of this study were 177 hypertensive patients who have been followed at Seoul National University Hospital outpatient clinic. The data was collected from August 20, 1998 to September 22, 1998, through survey using a self-report questionnaires and chart review. 24-hour urine sodium excretion was measured for validation of self-reported low-salt diet compliance from 22 patients who agreed for 24-hour urine collection. The questionnaires consist of general characteristics, disease-related characteristics, diet-related characteristics, and 4 scales: (1) Numeric scale (2) Knowledge of low-salt diet (3) Family support for low-salt diet (4) Low-salt diet compliance. The results were as follows: 1) The mean score of low-salt diet compliance was 38.97 +/- 9.26. The mean salt intake converted from 24-hour urine sodium was 16.81g/day, which was much greater than recommendation. The percentage of patients who were taking salt 6-8g/day was only 13.6%, and 8-10g/day was 13.6%. 2) The mean score of knowledge of low-salt diet was 5.12 +/- 1.81. The mean score of family support for low-salt diet was 30.08 +/- 8.81. The patients received emotional, instrumental, evaluative, and informational aspect of family support in sequence of amount. 3) Several factors were found as significant factors which influence low-salt diet compliance. Those were knowledge(p=.015), family support(p=.000), age(p=.039), diastolic pressure(p=.014), previous dietary habit(p= .000), duration of low-salt diet(p=.000), recognition of importance of low-salt diet on hypertension control(p=.000), and recognition of necessity of low-salt diet while antihypertensive drug therapy(p=.030). 4) Four significant predictive factors of low-salt diet compliance were identified: (1) Family support accounted for 24.8% of low-salt diet compliance (2) Previous dietary habit, 14.4% (3) Recognition of importance of low-salt diet on hypertension control, 3.7% (4) Diastolic pressure, 2.1%. Therefore, these factors accounted for 45.0% of low-salt diet compliance. In conclusion, low-salt diet compliance in hypertensive patients was very poor, which call for nursing intervention for enhancing low-salt diet compliance. It is necessary to provide practical knowledge of low-salt diet for hypertensive patients and family members.