Thiazide-associated hyponatremia in the elderly: what the clinician needs to know

Hyponatremia in geriatric patients

Hyponatremia is the most frequent electrolyte imbalance in geriatric medicine. Causes of hyponatremia were retrospectively analyzed in all in-patients treated in 2016 (N = 2267, 1564 women, 703 men, mean age ± standard deviation 81.9 ± 7.6 years). Any form of hyponatremia on admission, during the stay or on discharge was noted in 308 patients (13.6%, 231 women, 77 men; mean age ± standard deviation 83.1 ± 7.3 years, p = 0.009 vs. age of all patients). Women had a higher probability of developing hyponatremia compared to men (p = 0.019), 131 patients were hypovolemic, and dyspnea as an indicator of hypervolemia was noted in 71 patients.Only 12 patients suffering from hyponatremia (3.9%) did not receive any of the potentially sodium-lowering drugs assessed (diuretics, angiotensin-converting enzyme inhibitors, angiotensin II receptor antagonists, antidepressants, neuroleptics, nonsteroidal antirheumatics, carbamazepine, oxcarbazepine). The median number of drugs per patient potentially lowering the plasma sodium level was 3 and the maximum number was 7.Hypovolemic hyponatremia and the syndrome of inadequate antidiuretic hormone secretion were the most important causes of hyponatremia. Adverse drug effects were the main origins of both conditions. In patients with hyponatremia the drug load influencing plasma sodium level should be minimized, thiazide diuretics should be avoided and older individuals should receive a diet with sufficient salt content.

Mortality predictors of patients diagnosed with severe hyponatremia in the emergency department

PURPOSE

To determine the factors affecting mortality as a result of the analysis of the demographic and clinical characteristics and laboratory parameters of patients whose serum Na value was determined to be 125 mEq/L or below at the time of admission to the emergency department (ED).

METHOD

Patients over 18 years of age who admitted to the ED of a tertiary hospital between September 2021 and September 2022 and whose serum sodium level was determined to be 125 mEq/L and below were included in the study. Demographic and clinical characteristics, admission complaints, medications used, Charles comorbidity index (CCI), laboratory parameters, and outcomes of the patients included in the study were recorded in the data form.

RESULTS

Three hundred ninety-nine patients were included in the study. When the 30-day mortality of the patients is examined, the mortality rate was found to be 21.6%. In the analyses performed for the predictive power of laboratory parameters for mortality, it was determined that the highest predictive power among the predictive values determined by the area under the curve (AUC) was the albumin level (AUC 0.801, 95% CI 0.753-0.849, p < 0.001). In the binary logistic regression analysis, urea and albumin were independent predictors of 30-day mortality.

CONCLUSION

According to study data, albumin and urea levels are independent predictors of 30-day mortality in patients diagnosed with severe hyponatremia in the emergency department.

Alteration of the maximal renal water excretion capacity with kidney function and age in human

PURPOSE

The kidney's capability to concentrate and dilute urine is crucial to maintaining body fluid compartments and plasma osmolality. Advanced age and chronic kidney disease (CKD) result in decreased maximal urine concentration. Less is known regarding urine dilution ability. The primary purpose of this study was to determine the relationship between maximal renal water excretion and renal function, age, and gender in humans.

METHODS

This monocentric retrospective study includes patients referred to the Department of Clinical Physiology in Toulouse University Hospital to measure the glomerular filtration rate (mGFR) between April 2013 and February 2018. mGFR was assessed using inulin renal clearance and required ample hydration. We quantified the effects of age, gender and mGFR have on water excretion ability, which was assessed by minimal urinary osmolality (minUosm) and maximal free water clearance (maxCH2O).

RESULTS

666 patients were included (mean age 51 ± 14 years, 53% female). Mean mGFR was 82 ± 25 mL/min/1.73m2. MinUosm after hydration was higher in patients with renal insufficiency while maxCH2O was markedly lower. Age was also, with a weaker effect, associated with decreased in water excretion, independently of mGFR. MaxCH2O clearance was similar in both genders, whereas minUosm was lower in women, possibly resulting from a lower osmotic load.

DISCUSSION

This study shows a decrease in maximal urinary dilution capacity and free water clearance with CKD and age, without gender difference. These alterations are mild but must be considered when a significant water intake is required or in the case of hyponatremia.

Cumulative Incidence of Thiazide-Induced Hyponatremia : A Population-Based Cohort Study

BACKGROUND

According to drug labels, the frequency of thiazide-induced hyponatremia is unknown or uncommon to very rare (that is, <1 in 10 000 to <1 in 100), but the exact burden remains unclear.

OBJECTIVE

To estimate the increase in the cumulative incidence of hyponatremia using thiazide diuretics compared with nonthiazide antihypertensive drugs in routine clinical practice.

DESIGN

Population and register-based cohort study using target trial emulation.

SETTING

Denmark, 1 January 2014 to 31 October 2018.

PARTICIPANTS

Two target trials were emulated among persons aged 40 years or older who had no recent prescription for any antihypertensive drug, had no previous hyponatremia, and were eligible for the studied antihypertensive treatments. The first target trial emulation compared new use of bendroflumethiazide (BFZ) versus a calcium-channel blocker (CCB). The second target trial emulation compared new use of hydrochlorothiazide plus a renin-angiotensin system inhibitor (HCTZ-RASi; that is, combination pill) versus a RASi alone.

MEASUREMENTS

Two-year cumulative incidences of sodium levels less than 130 mmol/L using stabilized inverse probability of treatment-weighted survival curves.

RESULTS

The study compared 37 786 new users of BFZ with 44 963 of a CCB and 11 943 new users of HCTZ-RASi with 85 784 of a RASi. The 2-year cumulative incidences of hyponatremia were 3.83% for BFZ and 3.51% for HCTZ-RASi. The risk differences were 1.35% (95% CI, 1.04% to 1.66%) between BFZ and CCB and 1.38% (CI, 1.01% to 1.75%) between HCTZ-RASi and RASi; risk differences were higher with older age and higher comorbidity burden. The respective hazard ratios were 3.56 (CI, 2.76 to 4.60) and 4.25 (CI, 3.23 to 5.59) during the first 30 days since treatment initiation and 1.26 (CI, 1.09 to 1.46) and 1.29 (CI, 1.05 to 1.58) after 1 year.

LIMITATION

The study assumed that filled prescriptions equaled drug use, and residual confounding is likely.

CONCLUSION

Treatment initiation with thiazide diuretics suggests a more substantial excess risk for hyponatremia, particularly during the first months of treatment, than indicated by drug labeling.

PRIMARY FUNDING SOURCE

Independent Research Fund Denmark.

Thiazide-associated hyponatremia increases the risk of major adverse cardiovascular events among elderly Taiwanese patients

BACKGROUND

Thiazide-associated hyponatremia (TAH) has been supposed to increase the risk of major adverse cardiovascular events (MACE) in the elderly. Therefore, this study aimed to evaluate the association of TAH with the risk of MACE in elderly Taiwanese patients.

METHODS

Data from the longitudinal generation tracking database (LGTD 2010) of the Health and Welfare Data Science Center (HWDC) were retrospectively assessed. The TAH study group was defined as using > 30 cumulative daily defined doses (CDDDs) thiazide diuretics within one year before diagnosis of hyponatremia. The control group (1:3 propensity score matching) had no diagnosis of hyponatremia but had used > 30 CDDDs thiazide diuretics within one year. Data on MACE were extracted using International Classification of Diseases codes. Outcomes were assessed using a multivariable Cox proportional hazard model and Kaplan-Meier analysis.

RESULTS

A total of 1155 and 3465 individuals were enrolled in the TAH and the control groups, respectively. The rates of MACE (11.1% vs. 7.3%) and death (22.8% vs.12.2%) were significantly higher in the TAH group than the control group. In the TAH group, the adjusted HRs were 1.29 (CI 1.01 ‒ 1.65) for MACE, 1.39 (CI 1.19 ‒ 1.63) for all-cause death, and 1.61 (CI 0.90 ‒ 2.92) for stroke.

CONCLUSION

TAH in patients above 65-years-old is associated with a 29% higher risk of MACE, 39% higher risk of all-cause death, and 61% higher risk of stroke. This work suggests that thiazides prescription in elderly patients should be more careful. However, further research is required to confirm our findings.

Chronic Liver Disease in the Older Patient-Evaluation and Management

PURPOSE OF REVIEW

As our population ages, the number of elderly patients with advanced chronic liver disease (ACLD) will increase. In this review we explore risk factors for liver injury, noninvasive assessment of liver disease, complications of cirrhosis, and management of frailty and sarcopenia in the older patient with ACLD.

RECENT FINDINGS

Multiple guidelines regarding ACLD have been updated over the past few years. New cutoffs for FIB-4 and NAFLD (MASLD - Metabolic Dysfunction Associated Steatotic Liver Disease) fibrosis scores for elderly patients are being validated. Older patients with MASLD benefit from caloric restriction, exercise programs, and GLP-1 agonists. Patients with ACLD need to be screened for alcohol use disorder with modified scoring systems, and if positive, benefit from referral to chemical dependency programs. Carvedilol and diuretics may safely be used in the elderly for portal hypertension and ascites, respectively, with careful monitoring. Malnutrition, frailty, sarcopenia, and bone mineral disease are common in older patients with ACLD, and early intervention may improve outcomes. Early identification of ACLD in elderly patients allows us to manage risk factors for liver injury, screen for complications, and implement lifestyle and pharmacological therapy to reduce decompensation and death. Future studies may clarify the role of noninvasive imaging in assessing liver fibrosis in the elderly and optimal interventions for nutrition, frailty, sarcopenia, bone health in addition to reevaluation of antibiotic prophylaxis for liver conditions with rising antibiotic resistance.

From Crashing Waves to Crashing Sodium: A Rare Case of Nearly Asymptomatic Severe Hyponatremia

Hyponatremia refers to an abnormally low serum sodium level, and it is the most common electrolyte disorder encountered in the clinical setting. Despite its prevalence, hyponatremia can be challenging to clinically identify in some cases due to non-specific symptom presentation. In this case report, we illustrate the rare clinical course of a nearly asymptomatic patient with severe hyponatremia and discuss potential explanations for this uncommon presentation.

Pathophysiology of Drug-Induced Hyponatremia

Drug-induced hyponatremia caused by renal water retention is mainly due to syndrome of inappropriate antidiuresis (SIAD). SIAD can be grouped into syndrome of inappropriate antidiuretic hormone secretion (SIADH) and nephrogenic syndrome of inappropriate antidiuresis (NSIAD). The former is characterized by uncontrolled hypersecretion of arginine vasopressin (AVP), and the latter is produced by intrarenal activation for water reabsorption and characterized by suppressed plasma AVP levels. Desmopressin is useful for the treatment of diabetes insipidus because of its selective binding to vasopressin V2 receptor (V2R), but it can induce hyponatremia when prescribed for nocturnal polyuria in older patients. Oxytocin also acts as a V2R agonist and can produce hyponatremia when used to induce labor or abortion. In current clinical practice, psychotropic agents, anticancer chemotherapeutic agents, and thiazide diuretics are the major causes of drug-induced hyponatremia. Among these, vincristine and ifosfamide were associated with sustained plasma AVP levels and are thought to cause SIADH. However, others including antipsychotics, antidepressants, anticonvulsants, cyclophosphamide, and thiazide diuretics may induce hyponatremia by intrarenal mechanisms for aquaporin-2 (AQP2) upregulation, compatible with NSIAD. In these cases, plasma AVP levels are suppressed by negative feedback. In rat inner medullary collecting duct cells, haloperidol, sertraline, carbamazepine, and cyclophosphamide upregulated V2R mRNA and increased cAMP production in the absence of vasopressin. The resultant AQP2 upregulation was blocked by a V2R antagonist tolvaptan or protein kinase A (PKA) inhibitors, suggestive of the activation of V2R-cAMP-PKA signaling. Hydrochlorothiazide can also upregulate AQP2 in the collecting duct without vasopressin, either directly or via the prostaglandin E2 pathway. In brief, nephrogenic antidiuresis, or NSIAD, is the major mechanism for drug-induced hyponatremia. The associations between pharmacogenetic variants and drug-induced hyponatremia is an area of ongoing research.

A rare case of neurological dysfunction due to severe hyponatremia after carotid artery endarterectomy: A review of the clinical approach to hyponatremia

Development of severe hyponatremia after carotid endarterectomy procedure is rare. Several pathophysiological mechanisms related to the carotid endarterectomy procedure may infer an increased risk of developing this complication in specific populations.

Increased Mortality in Elderly Patients Admitted with Hyponatremia: A Prospective Cohort Study

Hyponatremia is the most common electrolyte disorder, commonly affecting older hospitalized individuals; however, the literature is not clear regarding its effect on mortality. The aim of this 2-year observational prospective cohort study was to evaluate the mortality and re-admission rates, the clinical and laboratory characteristics and the causes of hyponatremia in patients older than 65 years admitted with a corrected serum sodium of 130 mEq/L or less in an internal medicine ward of a tertiary Greek university hospital. During the observation period, 138 patients (mean age 80.5 years, 36.2% male) fulfilled the inclusion criteria and were prospectively followed for 1 year after admission. Symptoms of hyponatremia were present in 59.4% of patients. Hypovolemia was the main sole cause of hyponatremia, but in about one third of patients, hyponatremia was multifactorial. Only a low proportion of patients (12.3%) fulfilled the criteria of the syndrome of inappropriate antidiuresis (SIAD) at admission according to the current guidelines. The re-admission rates at 3- and 12-months following discharge was 34.2% and 51.8%, respectively. Mortality during hospitalization was 17.4% and was higher compared to non-hyponatremic admitted older patients, while the total mortality at 1 year after admission was 28.3%, indicating that hyponatremia at admission is a marker of significant mortality during and after hospitalization in elderly patients.

Severe Electrolyte Disturbances Complicated by Seizures and Acute Kidney Injury Within 10 Days of Starting Indapamide

Indapamide is one of the most effective and well-known anti-hypertensive medications. Electrolyte disturbances have been classically recognized as a typical side effect profile of indapamide. The most common electrolyte imbalance described with indapamide was hypokalemia; however, hyponatremia is being increasingly reported. In this case, we report a unique form of severe electrolytes derangement (hyponatremia, hypokalemia, hypophosphatemia, and hypocalcemia), which was complicated by seizures, rhabdomyolysis, and acute kidney injury that occurred within only 10 days of indapamide initiation. The patient was admitted to the medical intensive care unit for prompt electrolyte replacement and close monitoring. With the discontinuation of indapamide and the prompt replacement of the deficient electrolytes, the patient's condition has improved dramatically, and he was discharged in a good state of health. Electrolyte disturbances are expected to be seen with indapamide usage, and it might be associated with severe consequences like arrhythmias and seizures. This case report would raise awareness and add to the importance of closely following patients after prescribing indapamide.

Prevalence of hyponatremia among older inpatients in a general hospital

PURPOSE

This study aimed to explore the incidence, clinical features, etiology, and mortality of hyponatremia in older inpatients and thus provide preliminary data for an epidemiological study.

METHODS

Hospitalized older patients diagnosed with hyponatremia at the First Medical Center of PLA General Hospital during January 2013-December 2016 were stratified by serum sodium concentrations into mild (130- < 135 mmol/L), moderate (125- < 130 mmol/L) and severe hyponatremia groups (< 125 mmol/L). Etiologies, medication histories, hospitalization times, and outcomes were analyzed.

RESULTS

During the indicated period, 4364 older patients with hyponatremia were hospitalized, including 2934 men and 1430 women with an average age of 84.6 ± 3.5 years (range 80-104 years). The prevalence of hyponatremia was 24.7%. An analysis of common primary diseases identified respiratory diseases as the most frequent (25.0%), followed by tumors (23.1%), cardiovascular diseases (19.9%), central nervous system diseases (8.9%), and orthopedic diseases (6.1%). PPIs (59.7%), loop diuretics (57.4%), potassium-preserving diuretics (29.5%), ACEIs/ARBs (20.0%), thiazide diuretics (12.5%), and NSAIDs (12.4%) were the drugs most commonly associated with hyponatremia. The in-hospital mortality rate was 11.7%. Aggravated hyponatremia led to a prolonged hospitalization time. Moreover, when compared with mild hyponatremia, moderate and severe hyponatremia were associated with significant increases in in-hospital mortality (ORs 1.89 and 2.66, respectively; 95% CIs 1.54-2.33 and 2.06-3.43, respectively; P < 0.01).

CONCLUSIONS

Hyponatremia is a common complication in hospitalized older patients and is caused mainly by respiratory diseases, tumors, and cardiovascular diseases. Given the correlation between the degree of hyponatremia and prognosis, the early and accurate identification and treatment of this condition can reduce the associated morbidity and mortality.

Hyponatremia in Heart Failure: Pathogenesis and Management

Hyponatremia is a very common electrolyte abnormality, associated with poor short- and long-term outcomes in patients with heart failure (HF). Two opposite processes can result in hyponatremia in this setting: Volume overload with dilutional hypervolemic hyponatremia from congestion, and hypovolemic hyponatremia from excessive use of natriuretics. These two conditions require different therapeutic approaches. While sodium in the form of normal saline can be lifesaving in the second case, the same treatment would exacerbate hyponatremia in the first case. Hypervolemic hyponatremia in HF patients is multifactorial and occurs mainly due to the persistent release of arginine vasopressin (AVP) in the setting of ineffective renal perfusion secondary to low cardiac output. Fluid restriction and loop diuretics remain mainstay treatments for hypervolemic/dilutional hyponatremia in patients with HF. In recent years, a few strategies, such as AVP antagonists (Tolvaptan, Conivaptan, and Lixivaptan), and hypertonic saline in addition to loop diuretics, have been proposed as potentially promising treatment options for this condition. This review aimed to summarize the current literature on pathogenesis and management of hyponatremia in patients with HF.

Nutritional Considerations of Cardiovascular Diseases and Treatments

Nutritional considerations of many chronic diseases are not fully understood or taken into consideration in everyday clinical practice. Therefore, it is not surprising that high proportion of hospitalized patients with cardiovascular diseases remains underdiagnosed with malnutrition. Malnourished patients have increased risk of poor clinical outcomes, complications rate, prolonged hospital stay, more frequent rehospitalizations, and lower quality of life. The purpose of this review is to recapitulate recent data on nutritional considerations in cardiovascular medicine.

Atrioventricular conduction defect associated with severe hyponatremia

Hyponatremia is the most common electrolyte disorder among hospitalized patients and in the clinical setting. Patients with hyponatremia may develop a variety of symptoms, primarily neurological and gastrointestinal. Hyponatremia is more frequently encountered in patients with an underlying heart disease, particularly in the elderly. We hereby present a case of complete atrioventricular block in an elderly patient who had undergone aortic valve replacement and had been using thiazide. Complete atrioventricular block improved after sodium replacement therapy and no other cause of electrolyte disorder was documented.

Hyponatremia in the elderly: challenges and solutions

Decreased serum sodium concentration is a rather frequent electrolyte disorder in the elderly population because of the presence of factors contributing to increased antidiuretic hormone, the frequent prescription of drugs associated with hyponatremia and also because of other mechanisms such as the “tea and toast” syndrome. The aim of this review is to present certain challenges in the evaluation and treatment of hyponatremia in the elderly population and provide practical solutions. Hyponatremia in elderly subjects is mainly caused by drugs (more frequently thiazides and antidepressants), the syndrome of inappropriate antidiuretic hormone secretion (SIAD) or endocrinopathies; however, hyponatremia is multifactorial in a significant proportion of patients. Special attention is needed in the elderly population to exclude endocrinopathies as a cause of hyponatremia before establishing the diagnosis of SIAD, which then requires a stepped diagnostic approach to reveal its underlying cause. The treatment of hyponatremia depends on the type of hyponatremia. Special attention is also needed to correct serum sodium levels at the appropriate rate, especially in chronic hyponatremia, in order to avoid the osmotic demyelination syndrome. In conclusion, both the evaluation and the treatment of hyponatremia pose many challenges in the elderly population.

Severe Hyponatremia Presenting with Minimal Symptoms

Hyponatremia is a common electrolyte abnormality, however, encountering a patient with serum sodium level below 100 mEq/L and minimal symptoms is unusual. We present the case of an 86-year-old woman who was found to have serum sodium levels of 99 mEq/L. Her only complaint was difficulty in walking. On admission, and throughout her hospital stay, she did not have altered mental status, focal neurological deficits, or adverse outcomes. Her history, blood work, and urine studies pointed towards a diagnosis of thiazide-associated hyponatremia. Thiazide-associated hyponatremia can occur at any time during the course of thiazide administration. The first step that should be taken to manage this condition is discontinuing the medication. The lesson learned from this case is that the degree of hyponatremia does not always correlate with the severity of symptoms.

Hyponatraemia - presentations and management

Hyponatraemia is the most common electrolyte disturbance encountered in clinical practice. It is associated with -significant morbidity and mortality, thus appropriate investigation and treatment is essential. Hyponatraemia presents with a spectrum of clinical presentations ranging from no symptoms to life-threatening neurological sequelae. Hyponatraemia has multiple aetiologies and distinguishing the underlying aetiology facilitates appropriate treatment. This review provides an overview of the presentations and approaches to management of this common clinical condition.

The Hyponatremia Epidemic: A Frontier Too Far?

Hyponatremia is the most common electrolyte abnormality and is often neglected, especially in elderly and seemingly terminal patients. Hyponatremia can be asymptomatic or can cause symptoms ranging from nausea and lethargy to convulsions and coma. This condition has become increasingly common over time with a similar time course to the increase in adoption of low salt diets. The popularization of low salt may not be justified in people with normal kidney function in whom the compatible statistically based evidence that salt causes hypertension has been challenged by experimental evidence to the contrary.