Urinary Sodium-potassium Ratio Research Articles

Elevated level of urinary tellurium is a potential risk for increase of blood pressure in humans and mice

BackgroundPeople worldwide are routinely exposed to tellurium mainly via dietary ingestion. There has been no study to clarify the contribution of tellurium to blood pressure in humans or animals. MethodsIn this cross-sectional study conducted in a general population of 2592 residents in Japan, the associations of urinary tellurium levels with blood pressure and prevalence of hypertension were investigated. The potential sources of tellurium were also investigated. An interventional study in mice confirmed the effect of tellurium exposure on blood pressure. ResultsLinear and logistic regression analyses with consideration of confounders including urinary sodium–potassium ratio showed significant positive associations of urinary tellurium level with prevalence of hypertension and blood pressure. Cereals/beans and vegetables/fruits were determined to be potential dietary sources of tellurium exposure. Intermediary analysis suggested that increased intake of cereals/beans, but not that of vegetables/fruits, is positively associated with the tellurium-mediated risk of hypertension. Correspondingly, the mouse study showed that exposure to a putative human-equivalent dose of tellurium via drinking water increased blood pressure with an elevated level of urinary tellurium. The temporally increased blood pressure was decreased to the normal level by a break of tellurium exposure with a reduced level of urinary tellurium. ConclusionsThe interdisciplinary approach provided the first evidence that tellurium exposure is a potential risk for increase of blood pressure. Since the human urinary tellurium level in this study is comparable with the levels in general populations in other Asian and European countries in previous studies, exposure to tellurium may be a latent universal risk for hypertension.

The Association between Urinary Sodium-Potassium Ratio, Kidney Function, and Blood Pressure in a Cohort from the General Population

Introduction: Subclinical kidney dysfunction may contribute to salt-sensitive hypertension. We assessed the association between the urinary sodium-potassium ratio (Na/K ratio) and blood pressure (BP) in a general population cohort without diabetes, chronic kidney disease, cardiovascular disease, or treated hypertension. We investigated whether any such association was mediated by the kidney function markers measured glomerular filtration rate (mGFR), urinary albumin-creatinine ratio (ACR), and urinary epidermal growth factor-creatinine ratio (EGF-Cr). Methods: The Tromsø Study is a population-based study of inhabitants of the municipality of Tromsø, Northern Norway. Participants aged 50–62 years, without diabetes, chronic kidney disease, or cardiovascular disease, were invited to the substudy Renal Iohexol Clearance Survey in Tromsø 6 (RENIS-T6; 2007–09). For the present study, we excluded participants reporting the use of 1 or more antihypertensive agents, leaving 1,311 RENIS-T6 participants for a cross-sectional analysis. We measured office BP, 24-h ambulatory blood pressure (ABP), and mGFR using iohexol clearance. Na/K ratio, ACR, and EGF-Cr were measured in morning urine samples. Results: Urinary Na/K ratio was significantly associated with systolic office BP and ABP independently of cardiovascular risk factors and kidney function markers. A one-standard deviation unit increase in the Na/K ratio was associated with increased systolic ABP by 1.0 (0.3–1.6) mm Hg. Urinary Na/K ratio showed a stronger association with office BP than ABP. EGF-Cr, ACR, and mGFR did not mediate the relationship between urinary Na/K ratio and systolic BP. Conclusions: In a representative sample of the middle-aged North-European population without diabetes, chronic kidney disease, cardiovascular disease, or treated hypertension, there was a consistent association between urinary Na/K ratio and BP. The association with BP was not mediated through kidney function measures, suggesting a relationship between a diet with high sodium and low potassium and higher BP regardless of kidney function.

Causal association of genetically predicted urinary sodium-potassium ratio and upper urinary calculi.

The causality between the urinary sodium-potassium ratio and upper urinary calculi has not been clarified and easily affected by confounders. We performed two-sample andmultivariable Mendelian randomization (MR) analysis to evaluate the potential causal role of the urinary sodium-potassium ratio in upper urinary calculi. Data of the urinary sodium-potassium ratio (N = 326,938), upper urinary calculi (N = 337,199), and confounding factors including BMI (N = 336,107), ever-smoke (N = 461,066), hypertension (N = 218,754), diabetes (N = 218,792), and alcohol intake frequency (N = 462,346) were obtained from the IEU OpenGWAS Project database. The inverse-variance weighted (IVW), weighted median, and MR-Egger methods were used to estimate MR effects. The MR-Egger intercept test, Cochran's Q test, MR-PRESSO, leave-one-out method, and funnel plot were used for sensitivity analysis. A causal relationship was found between the urinary sodium-potassium ratio and upper urinary calculi (OR = 1.008, 95% CI = 1.002-1.013, P = 0.011). FinnGen data supported this conclusion (OR = 2.864, 95% CI = 1.235-6.641, P = 0.014). The multivariable Mendelian randomization analysis result showed that after adjusting for the effects of five confounders, the urinary sodium-potassium ratio was still positively correlated with upper urinary calculi (OR = 1.005, 95% CI = 1.001-1.009, P = 0.012). This study demonstrated a positive causal association between the urinary sodium-potassium ratio and upper urinary calculi using MR analysis. Timely identification of changes in urine composition and dietary regulation of sodium and potassium intake could greatly reduce the incidence of future urinary calculi.

Urinary sodium, urine potassium and sodium-potassium ratio, and influencing factors of family cooks and family members in six regions of China

Objective: To investigate the sodium intake, potassium intake, sodium- potassium ratio and influencing factors of family cooks and members in six regions of China. Methods: Using the multistage random sampling method, a total of 1 576 family cooks and their family members were recruited from 6 regions in China. Questionnaire survey and physical examination were conducted to collect basic information. 24 h urine was collected to test 24 h urinary sodium and potassium levels. Results: After excluding unqualified urine samples, a total of 1 530 people were included in the study. For all participants, 24 h urine sodium value was (4.39±1.93) g, 24 h urine potassium value was (1.59±0.62) g and sodium-potassium ratio was 5.02±2.18. 24 h urinary sodium was negatively correlated with age, female, junior high school education or above, and annual family income (P<0.05), and positively correlated with perceived salty taste, BMI and SBP (P<0.05). The 24 h urine potassium value was negatively correlated with eating out almost everyday (P<0.05), but positively correlated with BMI and unwillingness to reduct salt (P<0.05). The sodium-potassium ratio was negatively correlated with age, female and junior high school education or above annual family income (P<0.05), and positively correlated with perceived salty taste, SBP and eating out 3-5 d/week (P<0.05). Conclusions: The 24 h urinary sodium value and sodium potassium ratio of family cooks and family members in six regions of China are still at high level, while the 24 h urine potassium value is low, with multiple factors. Therefore, it is necessary to carry out long-term comprehensive salt reduction intervention for family cooks and their members.

Renal and dietary factors associated with hypertension in a setting of disadvantage in rural India.

Using a case-control design, we determined risk factors associated with hypertension in a disadvantaged rural population in southern India. Three hundred adults with hypertension and 300 age- and sex-matched controls were extensively phenotyped. Underweight (29%, body mass index < 18.0 kg m-2), chronic kidney disease (25%, estimated glomerular filtration rate <60 ml min-1 1.73 m-2) and anemia (82%) were highly prevalent. The ratio of sodium to potassium excretion was high (8.2). In multivariable conditional logistic regression of continuous variables dichotomized by their median value, hypertension was independently associated with greater abdominal adiposity as assessed by waist-hip ratio [odds ratio (95% confidence interval), 1.89 (1.21-2.97)], lesser protein intake as assessed by 24 h urea excretion [0.39 (0.24-0.65)], and lesser plasma renin activity [0.54 (0.35-0.84)]. Hypertension tended to be independently associated with lesser serum potassium concentration [0.66 (0.44-1.01), P = 0.06]. Furthermore, those with hypertension reported less frequent intake of vegetables and urinary sodium-potassium ratio correlated positively with serum sodium-potassium ratio (r = 0.18). Hypertension was also independently associated with lesser blood hemoglobin concentration [0.48 (0.26-0.88)]. Blood hemoglobin concentration was positively associated with serum iron (r = 0.41) and ferritin (r = 0.25) concentration and negatively associated with total iron binding capacity (r = -0.17), reflecting iron-deficiency anemia. Our findings indicate potential roles for deficient intake of potassium and protein, and iron-deficiency anemia, in the pathophysiology of hypertension in a setting of disadvantage in rural India. Imbalanced intake of potassium and sodium may be driven partly by deficient intake of vegetables or fruit.

Urinary sodium potassium ratio is associated with clinical success after adrenalectomy in patients with unilateral primary aldosteronism.

Background:The urinary sodium potassium (NaK) ratio is associated with dietary sodium and potassium intake and blood pressure, and it also reflects the activity of aldosterone. Herein we evaluated the value of the urinary NaK ratio in predicting the surgical outcomes of patients with unilateral primary aldosteronism (uPA).Methods:This non-concurrent prospective cohort study was conducted from 2011 to 2017 and included 241 uPA patients who had undergone adrenalectomy. Predictors of successful clinical outcomes were analyzed using logistic regression.Results:Among the 241 uPA patients, 197 (81.7%) achieved clinical complete or partial success. A urinary sodium potassium ratio <3 (odds ratio (OR): 2.5; 95% confidence interval (CI): 1.2–5.4; p = 0.015), body mass index <25 kg/m2 (OR: 2.82; 95% CI: 1.31–6.06; p = 0.008), renin <1 ng/mL/h (OR: 2.51; 95% CI: 1.01–6.21; p = 0.047) and mean preoperative blood pressure >115 mmHg (OR: 5.02; 95% CI: 2.10–11.97; p < 0.001) could predict clinical success after adrenalectomy. Furthermore, higher pre-treatment plasma aldosterone (OR: 1.014; 95% CI 1.005–1.024; p = 0.002) or lower serum potassium (OR: 0.523; 95% CI: 0.328–0.836; p = 0.007) were correlated with lower urinary NaK ratio (<3), and log urinary NaK ratio was positively correlated with serum C-reactive protein (β value 2.326; 95% CI 0.029–4.623; p = 0.047).Conclusions:uPA patients with a lower urinary NaK ratio, due to high plasma aldosterone and low serum potassium concentrations, were more likely to have clinical success after adrenalectomy. uPA patients with a higher urinary NaK ratio were associated with more severe inflammatory status, and possibly more resistant hypertension post-operatively.

Urinary sodium potassium ratio is associated with clinical success after adrenalectomy in patients with unilateral primary aldosteronism.

Urinary sodium potassium ratio is associated with clinical success after adrenalectomy in patients with unilateral primary aldosteronism.

Authors' response to a letter to the Editor from Zhu et al. re: Urinary sodium potassium ratio is associated with clinical success after adrenalectomy in patients with unilateral primary aldosteronism.

Authors' response to a letter to the Editor from Zhu et al. re: Urinary sodium potassium ratio is associated with clinical success after adrenalectomy in patients with unilateral primary aldosteronism.

980 Renal Resistive Index at the Level of Renal Arcuate Artery as a Predictor of Natriuresis in Cirrhotic Patients

INTRODUCTION: It has been postulated that the vasoconstriction at the level of renal arcuate artery plays a key role in the development of Hepatorenal syndrome(HRS). However, the measure of renal resistive index at the level of renal arcuate artery can provide a direct measure of renal hemodynamics among cirrhotics. The aim of this study is to determine the difference in the renal resistive index amongst both compensated as well as decompensated cirrhotics and to evaluate its association with natriuresis. METHODS: This prospective study included all consecutive cirrhotic patients visited gastroenterology clinic of our hospital from May 2018 to May 2019. After obtaining informed consent, the demographic parameters were noted along with a detailed drug history (Dose and duration of diuretics and beta blocker). Later on an ultrasound abdomen was also performed for documenting the features of chronic liver disease and the renal resistive index was noted. These patients were then stratified into two groups i.e. compensated cirrhosis and decompensated cirrhosis. Chi square test was applied and P value was calculated. RESULTS: A total of 60 patients were included in the study. The mean age of the patients was 40.3 ± 18.1, and were predominantly males 31(51.7%). Hepatitis C was the most common etiology for liver disease seen in 22 patients (36.7%).The mean CTP score, MELD and MELD sodium score were as follows: 7.9 ± 1.93, 15.2 ± 6.6 and 13.3 ± 4.2 respectively. Compensated liver disease was present in 16(26.7%) patients, while decompensated liver disease was present in 44(73.3%) patients. Mean renal resistive index of patient with compensated cirrhosis was 0.59 ± 0.04, while with decompensated cirrhosis was 0.62 ± 0.04. Patients with a higher RI had poor natriuresis as manifested by low urinary sodium potassium ratio &lt; 1.0 and AROC is 0.775. At the cut off value of RI = 0.615 sensitivity, specificity, positive predictive value and negative predictive value for nartriuresis was 65.0%, 70.0%, 73.3% and 60.1% respectively. Patient with higher RI value were having decompensated cirrhosis (P = 0.06, 0.62 vs 0.59) CONCLUSION: The renal resistive index at the level of arcuate artery were found to be higher among patients with decompensated cirrhosis. At a higher RI value ( &gt;0.615) patients had poor natriuresis. Therefore, RI can be used to predictor of natriuresis among cirrhotic patients. Key words:

An association of urinary sodium-potassium ratio with insulin resistance among Korean adults.

BACKGROUND/OBJECTIVESThis study was conducted to investigate the effects of sodium-potassium ratio on insulin resistance and sensitivity in Korean adults.SUBJECTS/METHODSSubjects were 3,722 adults (1,632 men and 2,090 women) aged 40–69 years participating in the Korean genome and epidemiology study_Ansan and Ansung study. Insulin resistance was assessed using homeostasis model assessment of insulin resistance (HoMA-IR) and fasting insulin, and insulin sensitivity was assessed by using the quantitative insulin sensitivity check index (QUICKI). The 24-h urinary sodium and potassium excretion were estimated from spot urinary samples using the Tanaka formula. The generalized linear model was applied to determine the association between urinary sodium-potassium ratio and insulin resistance.RESULTSHoMA-IR (P-value = 0.029, P-trend = 0.008) and fasting insulin (P-value = 0.017, P-trend = 0.005) levels were positively associated with 24-h estimated urinary sodium-potassium ratio in the multivariable model. QUICKI was inversely associated with 24-h estimated urinary sodium-potassium ratio in all models (P-value = 0.0002, P-trend < 0.0001 in the multivariate model).CONCLUSIONThe present study suggests that high sodium-potassium ratio is related to high insulin resistance and low insulin sensitivity. Decreasing sodium intake and increasing potassium intake are important for maintaining insulin sensitivity. Further studies are needed to confirm these findings in longitudinal studies.

The salt-taste threshold in untreated hypertensive patients

BackgroundThe salt-taste threshold can influence the salt appetite, and is thought to be another marker of sodium intake. Many studies have mentioned the relationship between the sodium intake and blood pressure (BP). The aim of this study was to evaluate the relationship between the salt-taste threshold and urinary sodium excretion in normotensive and hypertensive groups.MethodsWe analyzed 199 patients (mean age 52 years, male 47.3%) who underwent 24-h ambulatory BP monitoring (ABPM). Hypertension was diagnosed as an average daytime systolic BP of ≥135 mmHg or diastolic BP of ≥85 mmHg by the ABPM. We assessed the salt-taste threshold using graded saline solutions. The salt-taste threshold, 24-h urinary sodium and potassium excretion, and echocardiographic data were compared between the control and hypertensive groups.ResultsThe detection and recognition threshold of the salt taste did not significantly differ between the control and hypertensive groups. The 24-h urinary sodium excretion of hypertensive patients was significantly higher than that of the control group (140.9 ± 59.8 vs. 117.9 ± 57.2 mEq/day, respectively, p = 0.011). Also, the urinary sodium-potassium ratio was significantly higher in the hypertensive patients. There was no correlation between the salt-taste threshold and 24-h urinary sodium excretion.ConclusionsThe salt-taste threshold might not be related to the BP status as well as the 24-h urinary sodium excretion.

PP.05.01] EFFECT OF LONG-TERM ENRICHED POTASSIUM SALT INTAKE ON SALT REDUCTION IN CHINESE LIVING IN NURSING HOUSES

Objective: To explore whether long-term enriched potassium salt intake (KCL/NACL = 1:1 by weight) can achieve the purpose of salt reduction in Chinese living in nursing houses. Design and method: Participants were recruited from 28 nursing houses in 4 Northern provinces and Beijing City in 2012. The nursing houses were then randomized into 2 groups: normal salt (control group) and enriched potassium salt (intervention group), Health education about the benefits of salt restriction were provided for all participants. The follow-up visits including questionnaire and spot urine collection were carried out in 24–31 month and 48 month. The contents of questionnaire included the consumption of various high salt materials and number of dinners in the last month, the average salt intake per person per day at baseline and follow-up visits were calculated according to food composition table. The results of spot urine electrolytes and the salt consumption at baseline and follow-ups were used for data analysis. Results: Totally 2779 participants (intervention group 1336, control group 1443) were included in this study. The average salt intake per person per day for intervention group and control group at baseline were 12.86 ± 4.80 g and 12.58 ± 2.85 g respectively p = 0.85. No difference were found between average salt intake of two follow-up visits of control group with that at baseline (p = 0.69 and p = 0.59). But, the salt consumption were decreased in intervention group to 6.89 ± 1.78 g (24–31 month follow-up), 8.75 ± 3.34 g (48 month-follow-up), p < 0.001 compared with baseline. Urinary sodium potassium ratio (UNA/K) between control and intervention groups at baseline were 7.86 vs. 8.22, p = 0.12. While, at 48th month follow-up, the UNA/K of intervention group was significantly lower than control group 2.46 ± 1.71 vs. 4.21 ± 2.27, p < 0.001. Conclusions: Our study demonstrated that long-term enriched potassium salt intake can reduce dietary salt consumption and urine sodium potassium ratio. It might be an effective way for dietary salt restriction. Present data were from the cafeteria staff self-report and spot urine, further verification by 24 hours urine specimens were necessary.

1107 RELATIONSHIP BETWEEN 24-HOUR URINARY SODIUM POTASSIUM EXCRETION AND BLOOD PRESSURE AND ARTERIAL STIFFNESS IN HYPERTENSION PATIENTS

Objective: To investigate the relationship between 24-hour urinary sodium potassium excretion and blood pressure and arterial stiffness in hypertension patients. Methods: 224hypertension patients who didn’t take any antihypertensive medicine were randomly recruited. 24-hour urinary sodium (Na), potassium (K) and sodium potassium ratio (Na/K) were measured and calculated through 24-hour urine specimens. According to the results of 24-hour urinary sodium, patients were divided into three groups, group A (urinary sodium ≤ 100mmol/24 h), group B (urinary sodium >100 and ≤200mmol/24 h), and group C (urinary sodium >200mmol/24 h). All the subjects underwent 24 hours ambulatory blood pressure monitoring and brachial-ankle pulse wave velocity (baPWV) examination. Results: The urine Na excretion of group A, B, and C was(84.9 ± 12.7)mmol/24 h, (147.0 ± 26.7)mmol/24 h, and(256.1 ± 42.6) mmol/24 h respectively, corresponding to daily salt intake 4.8 g, 8.46 g, 15.14 g. Group C who had the highest salt intake was significantly higher than group A in 24 hours, day, and night blood pressure. Multiple linear regression revealed urinary Na was independently associated with 24 hours, day, and night blood pressure. The baPWV of group A,B,C was (1621.6 ± 288.3)cm/s,(1645.7 ± 301.0)cm/s, and (1741.9 ± 307.0)cm/s respectively, with group C higher than group A and B (P = 0.032,P = 0.046). Multiple linear regression indicated urinary Na and Na/K were independently associated with baPWV (P<0.05), while urinary K was not (Table1). Table 1 Multiple linear regression for association between urinary electrolytes and baPWVConclusion: Not only urinary sodium and sodium potassium ratio are associated with blood pressure, but also are independently associated baPWV. Moreover, this relationship between urinary electrolytes and arterial stiffness is independent of blood pressure.

Oral contraceptive use in girls and alcohol consumption in boys are associated with increased blood pressure in late adolescence

Lifestyle behaviours established during adolescence may adversely affect blood pressure (BP) and contribute to gender differences in cardiovascular risk in adulthood. We aimed to assess the association of health behaviours with BP in adolescents, using data from the Western Australian Pregnancy (Raine) Study. Cross-sectional analysis on 1248 Raine Study adolescents aged 17 years, to examine associations between lifestyle factors and BP. Boys had 8.97 mmHg higher systolic BP, as compared with girls. The 30% of girls using oral contraceptives (OC) had 3.27 and 1.74 mmHg higher systolic and diastolic BP, respectively, compared with non-users. Alcohol consumption in boys, increasing body mass index (BMI) and the sodium-potassium ratio were associated with systolic BP. We found a continuous relationship between BMI and systolic BP in both genders; however, the gradient of this relationship was significantly steeper in boys, compared with girls not taking OC. In boys, systolic BP was 5.7 mmHg greater in alcohol consumers who were in the upper quartile of BMI and the urinary sodium-potassium ratio compared with teetotallers in the lowest quartile. In girls, systolic BP was 5.5 mmHg higher in those taking OC, in the highest BMI and urinary sodium-potassium ratio quartile as compared to those not taking the OC pill and in the lowest quartile. In addition to gender-related differences in the effects of adiposity on BP, we found lifestyle-related health behaviours such as high salt intake for both sexes, consumption of alcohol in boys, and OC use in girls were important factors associated with BP measurements in late adolescence. This suggests that gender-specific behavioural modification in adolescence may prevent adult hypertension.

The effect of potassium supplementation in persons with a high-normal blood pressure: Results from phase I of the Trials of Hypertension Prevention (TOHP)

We conducted a randomized, double-blind, placebo-controlled trial oral potassium chloride supple mentation (60 mmol/d) in 353 men and women with an initial average diastolic blood pressure between 80 and 89 mm Hg. In the active (n = 178) campared to the placebo (n = 175) treatment group, the urinary potassium level was significandy (p < 0.001) increased by an average of 44.0 and 42.3 mmol/24 h following 3 and 6 months of therapy, respectively. Compared to placebo, active treatment was associated with a small (mean = 1.8 mm Hg) but significant (p = 0.04) reduction in diastolic blood pressure following 3 months of therapy. Following 6 months, however, this apparent treatment effect had virtually disappeared (mean reduction in diastolic blood pressure = 0.3 mm Hg). There was no significant effect of potassium supplementation on systolic blood pressure at either follow-up visit. There was a significant, independant, dose-response relationship between change in both 24-hour urinary potassium excretion and urinary sodium-potassium ratio and the corresponding change in diastolic blood pressure (−1.49 mm Hg for the highest versus the lowest quartile of change in urinary potassium excretion).

Rise of blood pressure with age. New evidence of population differences.

Epstein and Eckoff in 1967 devised a scheme to summarize population differences in the rise of mean values of systolic blood pressure by age in accordance with their slopes and levels. For the first time, the validity of this scheme can be examined with data from a single study, INTERSALT. This study included 52 populations in 32 countries. On the basis of these data, collected in an exceptionally well-standardized mode under a common protocol, the diversity of populations in the slopes of age differences in median values of systolic blood pressure has been strongly reconfirmed. Populations with no increase in median systolic blood pressure were again observed and remained exceptional. The analyses of these data also indicate a positive relation between the slope of rising systolic blood pressure with age and urinary sodium, urinary sodium-potassium ratio, and reported alcohol consumption as well as a negative association between urinary potassium excretion and blood pressure slope. The present analyses therefore add to the previous knowledge and results published by the INTERSALT investigators in the following three respects: (1) they relate INTERSALT results to the postulated biological gradient of variation among populations as presented by Epstein and Eckoff, including explanatory variables; (2) they demonstrate strong correlation between ranks of median blood pressure at 40 to 49 years and values at 20 to 29 years; and (3) they therefore support the original Epstein and Eckoff concept of population variation, link this with blood pressure risk factors, and call attention to the large degree of population differences already evident among populations at 20 to 29 years of age.

Advantages and disadvantages of fludrocortisone or saline load in preventing post-spaceflight orthostatic hypotension

The purpose of this study was to compare the effectiveness of saline load to fludrocortisone (florinef) as countermeasures for reduced plasma volume and orthostatic intolerance after spaceflight. Eleven males (ages 30–50 yr) underwent a 3-day ambulatory baseline period followed by 7 days of 6° head-down bedrest, during which cardiopulmonary and arterial baroreflex sensitivity and plasma volume (PV) were determined. During pre-bedrest and 2.5 h after treatment on day 8, PV was also measured and subjects underwent a 15-min unsupported stand test. Treatments consisted of 8 salt tablets (1 g NaCl per tablet) and 960 ml of water in 5 subjects and 0.6 mg (0.2 mg × 3) over 24 h in the other 6 subjects. PV decreased by 12% on day 7 of bedrest. This was restored on day 8 by florinef but not by saline load. The effect of florinef on PV was paralleled by decreases in urine volume and the urinary sodium potassium ratio. Reduced PV was associated with greater vascular resistance for the same drop in central venous pressure, suggesting less vasoconstriction reserve after bedrest. Carotid baroreflex control of heart rate was attenuated after 7 days of bedrest. Both baroreflex functions were restored by florinef but not saline load. Only 1 of 6 subjects showed syncopal symptoms in the florinef-treated group, whereas 4 of 5 subjects did so in the saline-load group. Acute florinef treatment appears to have distinct advantages as a protective measure for post-bedrest orthostatic intolerance, not only through its salt retaining, volume-expanding mineralcorticoid effect, but possibly through its actions on baroreflex and sympathetic functions.

Aggregation of Dietary Calories, Fats, and Sodium in Mexican-American and Anglo Families

There seems to be a consensus that family influences on dietary habits are important, but few studies have addressed this issue directly. To clarify inconsistent findings, we studied the aggregation of dietary fats, sodium, and calories in 95 Anglo and 111 Mexican-American families. Their diet was determined by 24-hour recall, a three-day food record, and a food frequency questionnaire, along with a measure of the urinary sodium-potassium ratio. There was evidence of moderate aggregation of all dietary variables in both ethnic groups. In Anglo families, spouse-spouse, but not sibling-sibling, correlations tended to be significant. The diets of the younger children, but not the older children, were related to their parents' diets. In Mexican-American families, both spouse-spouse and sibling-sibling correlations tended to be significant. The mothers' diets were more highly correlated with the children's diets than were the fathers'.

Salt consumption, body fatness and blood pressure of the Gidra in lowland Papua

The Gidra population in lowland Papua New Guinea, having lived as a no‐salt culture, is now subjected to modernization. In 1981, salt consumption, body fatness and blood pressures were measured for people in four ecologically different villages. Daily salt consumption of individuals was estimated from the sodium level per unit weight of creatinine in the morning urine and the daily urinary excretion of creatinine (estimation from fat free mass). The estimated value significantly correlated (r=0.53) with actually measured value in 30 selected subjects. Estimated sodium consumption and the urinary sodium potassium ratio were generally lower in remote villages from the town, and the salt consumption levels were less than 5 g/day/person in all the villages. Body fatness, calculated from the two skinfold values, was variable with sex, age group and village, the most being in the females in a coastal village which was adjacent to the town. The age‐related increment of blood pressures was significant only in fem...

Comparison of Spironolactone Tablet Dosage Forms in Healthy Humans

A single-dose, crossover, comparative study of 25- and 100-mg spironolactone tablets was undertaken in 39 healthy males. Following a total dose of 200 mg, blood samples were drawn at 0, 1, 2, 3, 4, 6, and 24hr and a single collection of urine was taken after the initial 6hr. The dethioacetylated active metabolite was measured in these specimens and was employed as the indicator of drug absorption and elimination. A comprehensive statistical analysis, including: (a) multivariate hour-by-hour comparisons with plasma aldadiene levels, (b) comparisons with total plasma area and total urinary metabolite level, (c) bivariate comparisons with peak plasma aldadiene levels, and (d) urinary sodium-potassium ratio responses, examines the question of the biological equivalence of these two spironolactone preparations. The primary discriminators for comparing the two dosage forms were found to be plasma metabolite levels at Hours 3 and 4, peak plasma metabolite level, and total 24-hr area under the plasma level curve. Moreover, a single plasma level by itself does not appear to be sufficient to test for biological equivalence, so correlations among levels should not be ignored. The mean peak plasma metabolite levels for the 25- and 100-mg formulations reached 67.8 and 61.6 μg/100 ml, respectively, each at the same mean time of 160min.