Impact of diuretic therapy-associated electrolyte disorders present on admission to the emergency department: a cross-sectional analysis

Diuretics are among the most commonly prescribed medications and, due to their mechanisms of action, electrolyte disorders are common side effects of their use. In the present work we investigated the associations between diuretics being taken and the prevalence of electrolyte disorders on admission as well as the impact of electrolyte disorders on patient outcome.

Diuretic-induced hyponatremia and osteoporotic fractures in patients admitted to the emergency department

Hyponatremia is a complication of diuretic treatment and has been recently identified as a novel factor associated with osteoporosis and fractures. The impact of diuretic-associated electrolyte disorders on osteoporotic fractures (OF) has rarely been studied systematically.

Thiamine supplementation in symptomatic chronic heart failure: a randomized, double-blind, placebo-controlled, cross-over pilot study

Diuretic treatment for heart failure may lead to an increased urinary thiamine excretion and in long-term thiamine deficiency, which may further compromise cardiac function. This study evaluated the effect of high dose thiamine supplementation in heart failure patients.

[Arterial Hypertension - when are which combination therapies useful?]

Arterial hypertension is a widely prevalent risk factor for cardiovascular diseases with well documented harmful effects on the heart and the vascular system. Despite a broad antihypertensive drug armamentarium control of hypertension is worldwide suboptimal. Daily practice as well as large intervention trials show that single-drug therapy often fails to adequately control blood pressure (BP). Therefore, the early introduction of a combination therapy may lead to a better and more rapid BP lowering effect, particularly in patients with more than stage I hypertension or in patients with mild hypertension and high cardiovascular risk. In addition, side effects of an antihypertensive drug can be prevented by a meaningful (low dose) combination with a second antihypertensive agent. Moreover, combination of antihypertensive drugs, especially if provided fixed, may substantially improve compliance. However, the choice of the drug combination primarily relates on the demographic features and co-morbidities of the patient. Although BP lowering is the main determinant of cardiovascular risk reduction in the treatment of hypertension, some antihypertensive drugs may exhibit protective effects beyond BP reduction that have to be considered when antihypertensive drugs are combined. In recent large intervention studies, the combination of an ACE inhibitor with a calcium channel blocker was especially advantageous in high risk hypertensive patients. The addition of a thiazide type diuretic to a blocker of the renin-angiotensin system is also sensible and popular with numerous available fixed combinations.

[Hypertension therapy in patients with renal artery stenosis]

Renovascular hypertension is due to reduced renal parenchymal perfusion. The correct diagnosis can be difficult. It is important to note that the demonstration of renal artery stenosis in a patient with hypertension does not necessarily constitute renovascular hypertension. Often, clinically nonsignificant and asymptomatic renal artery stenosis are found in patients with essential hypertension, or renal failure of other origin. Renovascular disease is a complex disorder with various clinical presentations. In patients with significant renovascular hypertension plasma renin is increased. For this reason the therapy aims to block the renin-angiotensin-aldosterone system. Bilateral renal artery stenosis causes renal sodium retention. In this situation a diuretic drug has to be added to the therapy. Endovascular or surgical therapy has to be considered in patients with flash pulmonary edema or fibromuscular dysplasia. The control of cardiovascular risk factors is important.

[Hypercalcemia in sarcoidosis--case report, prevalence, pathophysiology and therapeutic options]

Hypercalcemia is a highly prevalent complication of sarcoidosis. A medical history of a patient with sarcoidosis is shown as case report. Depending on the population studied about 2-63% of sarcoidosis patients show hypercalcemia. The major difference in the prevalence of hypercalcemia may be in part due to the undulating course of subacute sarcoidosis, so hypercalcemia may be missed when serum calcium is not frequently measured. Hypercalciuria appears to be twice as prevalent then hypercalcemia and should be looked for in every sarcoidosis patient. Hypercalcemia in sarcoidosis is due to the uncontrolled synthesis of 1,25-dihydroxyvitamin D3 by macrophages. 1,25-dihydroxyvitamin D3 leads to an increased absorption of calcium in the intestine and to an increased resorption of calcium in the bone. Immunoregulatory properties have been ascribed to 1,25-dihydroxyvitamin D3. It is an important inhibitor of interleukin-2 and of interferon-gamma-synthesis, two cytokines that are important in granuloma formation in sarcoidosis. It is thought that 1,25-dihydroxyvitamin D3 counterregulates uncontrolled granuloma formation. Treatment of hypercalcemia depends on the serum level of hypercalcemia and its persistence. Generally sarcoidotic patients should be advised to avoid sun exposition to reduce vitamin D3 synthesis in the skin, to omit fish oils that are rich of vitamin D and to produce more than two liters urine a day by adapting fluid intake. Although severe hypercalcemia seems to be rare, glucocorticosteroid treatment should be started if corrected total calcium level rises beyond 3 mmol/l. If hypercalcemia is symptomatic, treatment should be started even at lower levels. Glucocorticosteroids act by inhibition of the overly 1alpha-hydroxylase activity of macrophages. Alternatively, treatment with chloroquine or ketoconazole can be established. If isolated hypercalciuria without hypercalcemia is present with evidence for recurrent nephrolithiasis, patients can be treated with a thiazide diuretic.

A thiazide test for the diagnosis of renal tubular hypokalemic disorders

Although the diagnosis of Gitelman syndrome (GS) and Bartter syndrome (BS) is now feasible by genetic analysis, implementation of genetic testing for these disorders is still hampered by several difficulties, including large gene dimensions, lack of hot-spot mutations, heavy workup time, and costs. This study evaluated in a cohort of patients with genetically proven GS or BS diagnostic sensibility and specificity of a diuretic test with oral hydrochlorothiazide (HCT test). Forty-one patients with GS (22 adults, aged 25 to 57; 19 children-adolescents, aged 7 to 17) and seven patients with BS (five type I, two type III) were studied; three patients with "pseudo-BS" from surreptitious diuretic intake (two patients) or vomiting (one patient) were also included. HCT test consisted of the administration of 50 mg of HCT orally (1 mg/kg in children-adolescents) and measurement of the maximal diuretic-induced increase over basal in the subsequent 3 h of chloride fractional clearance. All but three patients with GS but no patients with BS and pseudo-BS showed blunted (<2.3%) response to HCT; patients with BS and the two patients with pseudo-BS from diuretic intake had increased response to HCT. No overlap existed between patients with GS and both patients with BS and pseudo-BS. The response to HCT test is blunted in patients with GS but not in patients with BS or nongenetic hypokalemia. In patients with the highly selected phenotype of normotensive hypokalemic alkalosis, abnormal HCT test allows prediction with a very high sensitivity and specificity of the Gitelman genotype and may avoid genotyping.

[Fixed-combination of losartan/hydrochlorothiazide 100 mg/25 mg. Tolerability and efficacy on blood pressure measured in the practice and for 24 hours]

BACKGROUND: A high proportion of patients with essential hypertension need a combination therapy to reach the therapeutic goal. In the present study, the tolerability and efficacy of a fixed, once daily combination of the AT1 blocker Losartan (100 mg) and the diuretic hydrochlorothiazide (HCTZ) (25 mg) for patients in the real-life situation was investigated. Special consideration was given to the results of ambulatory 24-hourblood pressure (ABP) measurements. METHODS: The open label, prospective non-interventional surveillance study took place from October 2005 to June 2006. A total of 1139 patients over 18 years in age were included whose blood pressures could not be adequately treated with HCTZ alone and for whom an individual dose titration for Losartan and HCTZ had already been performed. RESULTS: The average age (+/- standard deviation) of the patients was 61.2 +/- 11.6 years; 55.8% were men. Comorbidities were common. Specifically, left ventricular hypertrophy was present in 3.1% of the patients, coronary heart disease in 30.1%, chronic heart failure in 11.8% and status post myocardial infarction in 10.5%, respectively. In addition to the Losartan/HCTZ treatment, 61.0% of the patients received a second antihypertensive medicine. After an average treatment duration of 50.4 +/- 17.2 days, the base line systolic blood pressure of 160.8 +/- 16.3 mmHg decreased by 24.0 +/- 17.0 mmHg (-14.4%) and the diastolic blood pressure of 94.4 +/- 9.9 mmHg decreased by 11.8 +/- 10.2 mmHg (-11.8%). For the ABP measurements, the overall average systolic and diastolic blood pressures fell by 16.9 +/- 14.2 mmHg and 8.8 +/-10.3 mmHg, the day average by 17.3 +/- 14.8 mmHg and 9.0 +/- 10.2 mmHg and the night average by 15.1 +/- 17.6 mmHg and 7.8 +/- 11.7 mmHg, respectively. In twelve of the 1139 patients (1.1%), a total of 15 adverse events occurred. A causal connection with the medication was suspected in only in one case (one patient with three). CONCLUSION: The combination of Losartan/HCTZ 100/25 mg, as the exclusive therapy or in addition to other antihypertensive medicines, was for patients, many of whom who had comorbidities, in the real-life situation well tolerated and effective. The efficacy was demonstrated also during the night through ABP.

Serum lipoproteins during treatment with the antihypertensive agent indapamide

Considering the documented, potentially undesirable influence of various thiazide-type or loop diuretics on serum lipoproteins, we prospectively investigated in 69 men (mean age +/- SEM, 32 +/- 1 years) the metabolic effects of the new diuretic-antihypertensive compound indapamide. Compared to placebo, indapamide (2.5 mg/day) given for 6 to 8 weeks lowered (p less than 0.02 to less than 0.001) blood pressure (supine values from 148/98 +/- 3/2 to 137/93 +/- 3/2) in 29 men with mild to moderate essential hypertension, but not in 40 healthy men. In both groups, significant (p less than 0.05 to less than 0.001) decreases in body weight (-0.8 kg) and plasma potassium (-0.6 mmol/L), and increases in plasma uric acid (+20%), renin activity (+200%), and aldosterone documented good compliance. There were no significant changes in total cholesterol (in all subjects, from 208 +/- 6 to 213 +/- 6 mg/dl), low- or very low-density lipoprotein (VLDL) cholesterol (127 +/- 6 to 129 +/- 6 and 21 +/- 1 to 21 +/- 2 respectively), high-density lipoprotein cholesterol (50 +/- 1 to 51 +/- 1 mg/dl), total triglycerides (Tg) (108 +/- 5 to 112 +/- 6 mg/dl), VLDL-Tg, apoproteins A1 and A2, plasma glucose, epinephrine, norepinephrine, sodium, calcium, magnesium, and creatinine; apoprotein B (84 +/- 2 to 88 +/- 3 mg/dl) and plasma insulin after glucose loading dose tended to be increased minimally. The absence of distinct lipoprotein alterations after short-term indapamide treatment may be of clinical and epidemiological interest.

When do combinations of diuretics make sense?

Diuretics are commonly prescribed by physicians to contract the ECF volume. In two clinical situations combining different classes of diuretics make sense: First, if a loop diuretic at maximal dose alone does not lead to sufficient diuresis or second, if the side effect of a diuretic needs to be corrected by adding a diuretic of another class. The latter is clinically often used to counteract loop or thiazide diuretic-induced hypokalemia by the addition of a potassium sparing diuretic. Key to a reasonable combination of diuretics is understanding of the pharmaco-kinetics and knowledge of the molecular targets of the diuretics involved.

Electrolyte disorders and in-hospital mortality during prolonged heat periods: a cross-sectional analysis

BACKGROUND Heat periods during recent years were associated with excess hospitalization and mortality rates, especially in the elderly. We intended to study whether prolonged warmth/heat periods are associated with an increased prevalence of disorders of serum sodium and potassium and an increased hospital mortality. METHODS In this cross-sectional analysis all patients admitted to the Department of Emergency Medicine of a large tertiary care facility between January 2009 and December 2010 with measurements of serum sodium were included. Demographic data along with detailed data on diuretic medication, length of hospital stay and hospital mortality were obtained for all patients. Data on daily temperatures (maximum, mean, minimum) and humidity were retrieved by Meteo Swiss. RESULTS A total of 22.239 patients were included in the study. 5 periods with a temperature exceeding 25 °C for 3 to 5 days were noticed and 2 periods with temperatures exceeding 25 °C for more than 5 days were noted. Additionally, 2 periods with 3 to 5 days with daily temperatures exceeding 30 °C were noted during the study period. We found a significantly increased prevalence of hyponatremia during heat periods. However, in the Cox regression analysis, prolonged heat was not associated with the prevalence of disorders of serum sodium or potassium. Admission during a heat period was an independent predictor for hospital mortality. CONCLUSIONS Although we found an increased prevalence of hyponatremia during heat periods, no convincing connection could be found for hypernatremia or disorders of serum potassium.

Age-related variety in electrolyte levels and prevalence of dysnatremias and dyskalemias in patients presenting to the emergency department.

BACKGROUND It was found that age and female gender are predisposing factors for hyponatremia in patients taking thiazides. OBJECTIVE To investigate whether a relationship exists between age and gender and serum sodium and potassium as well as the prevalence rates in a large population of patients presenting to the emergency department of a university hospital. METHODS In this retrospective analysis we gathered data on age, gender and current diuretic medication of all patients admitted to the emergency department of a large university hospital with measurement of serum sodium and potassium between January 1, 2009 and December 31, 2010. Prevalence rates of and risk factors for electrolyte disorders were calculated on the basis of these data. RESULTS A total of 20,667 patients were included in the analysis. Serum sodium levels declined significantly with increasing age while serum potassium rose, independent of diuretic medication at presentation. The prevalence rates of hyponatremia and hyperkalemia increased from 2.3% for hyponatremia in patients aged 16-21 years to 16.9% in patients aged >80 years and from 0.8% for hyperkalemia to 10.4%. In the regression analysis, age >60 years was a predictor for the presence of hyponatremia and hyperkalemia as was current use of diuretic medication. Male gender was associated with a decreased prevalence of hyponatremia and hypokalemia, while it was a predictor of hyperkalemia. CONCLUSIONS Sodium levels were lower with increasing age, independent of diuretic intake, while potassium levels were higher. We found dramatically increasing prevalences of hyponatremia and hyperkalemia with increasing age, while no such effect could be found for hypernatremia and hypokalemia.

Impact of proton pump inhibitor use on magnesium homoeostasis: a cross-sectional study in a tertiary emergency department.

BACKGROUND To date, the use of proton pump inhibitors (PPIs) has been associated with a low risk of hypomagnesaemia and associated adverse outcomes. We hypothesised that a better risk estimate could be derived from a large cohort of outpatients admitted to a tertiary emergency department (ED). METHODS A cross-sectional study was performed in 5118 patients who had measurements of serum magnesium taken on admission to a large tertiary care ED between January 2009 and December 2010. Hypomagnesaemia was defined as a serum magnesium concentration < 0.75 mmol/l. Demographical data, serum electrolyte values, data on medication, comorbidities and outcome with regard to length of hospital stay and mortality were analysed. RESULTS Serum magnesium was normally distributed where upon 1246 patients (24%) were hypomagnesaemic. These patients had a higher prevalence of out-of-hospital PPI use and diuretic use when compared with patients with magnesium levels > 0.75 mmol/l (both p < 0.0001). In multivariable regression analyses adjusted for PPIs, diuretics, renal function and the Charlson comorbidity index score, the association between use of PPIs and risk for hypomagnesaemia remained significant (OR = 2.1; 95% CI: 1.54-2.85). While mortality was not directly related to low magnesium levels (p = 0.67), the length of hospitalisation was prolonged in these patients even after adjustment for underlying comorbid conditions (p < 0.0001). CONCLUSION Use of PPIs predisposes patients to hypomagnesaemia and such to prolonged hospitalisation irrespective of the underlying morbidity, posing a critical concern.

Efficacy and safety of calcium channel blocker/diuretics combination therapy in hypertensive patients: a meta-analysis.

Although recent guidelines recommend the combination of calcium channel blockers (CCBs) and thiazide (-like) diuretics, this combination is not widely used in clinical practice. The aim of this meta-analysis was to assess the efficacy and safety of this combination regarding the following endpoints: all-cause and cardiovascular mortality, myocardial infarction, and stroke. Four studies with a total of 30,791 of patients met the inclusion criteria. The combination CCB/thiazide (-like) diuretic was associated with a significant risk reduction for myocardial infarction (risk ratio [RR], 0.83; 95% confidence interval [CI], 0.73-0.95) and stroke (RR, 0.77; CI, 0.64-0.92) compared with other combinations, whereas it was similarly effective compared with other combinations in reducing the risk of all-cause (RR, 0.89; CI, 0.75-1.06) and cardiovascular (RR, 0.89; CI 0.71-1.10) mortality. Elderly patients with isolated systolic hypertension may particularly benefit from such a combination, since both drug classes have been shown to confer cerebrovascular protection.

Calcium Disorders in the Emergency Department: Independent Risk Factors for Mortality.

BACKGROUND Calcium disorders are common in both intensive care units and in patients with chronic kidney disease and are associated with increased morbidity and mortality. It is unknown whether calcium abnormalities in unselected emergency department admissions have an impact on in-hospital mortality. METHODS This cross-sectional analysis included all admissions to the Emergency Department at the Inselspital Bern, Switzerland from 2010 to 2011. For hyper- and hypocalcaemic patients with a Mann-Whitney U-test, the differences between subgroups divided by age, length of hospital stay, creatinine, sodium, chloride, phosphate, potassium and magnesium were compared. Associations between calcium disorders and 28-day in-hospital mortality were assessed using the Cox proportional hazard regression model. RESULTS 8,270 patients with calcium measurements were included in our study. Overall 264 (3.2%) patients died. 150 patients (6.13%) with hypocalcaemia and 7 patients with hypercalcaemia (6.19%) died, in contrast to 104 normocalcaemic patients (1.82%). In univariate analysis, calcium serum levels were associated with sex, mortality and pre-existing diuretic therapy (all p<0.05). In multivariate Cox regression analysis, hypocalcaemia and hypercalcaemia were independent risk factors for mortality (HR 2.00 and HR 1.88, respectively; both p<0.01). CONCLUSION Both hypocalcaemia and hypercalcaemia are associated with increased 28-day in-hospital mortality in unselected emergency department admissions.