Sex differences in clinical characteristics and outcomes in the CLOROTIC (combining loop with thiazide diuretics for decompensated heart failure) trial

Diuretics: a review of the pharmacology and effects on glucose homeostasis

Thiazides, thiazide-like and loop diuretics are commonly prescribed to manage hypertension and heart failure. The main mechanism of action of these diuretics involve inhibition of Na+ reabsorption in the kidneys, leading to increased urine production. While effective, diuretics, particularly hydrochlorothiazide, have been linked to altered glucose metabolism and other metabolic issues. These disruptions in fuel homeostasis are not clearly related to their primary action of fluid management, raising concerns for patients with metabolic syndrome, in which high blood pressure coexists with obesity, insulin resistance, glucose intolerance and dyslipidemia. In this review, we conducted an extensive examination of existing literature on these classes of diuretics, covering publications from the late 1950s to the present. Our objective was to investigate the origins, development and current understanding of the widely recognized association between the use of diuretics in general and their potential negative impact on glucose homeostasis. We focused on the clinical and experimental evidence of the most commonly prescribed diuretics: hydrochlorothiazide, chlorthalidone, bumetanide and furosemide. On one hand, the clinical evidence supports the hypothesis that the metabolic effects on glucose homeostasis are primarily linked to hydrochlorothiazide, with little, if any impact observed in other diuretics. In addition, these metabolic effects do not appear to be related to their diuretic action or intended pharmacological targets, raising concerns about the long-term metabolic impact of specific diuretics, particularly in vulnerable populations, including those with metabolic syndrome. On the other hand, the experimental evidence using animal models suggest variable effects of diuretics in insulin secretion and general glucose metabolism. Although the mechanisms involved are not clearly understood, further research is needed to uncover the molecular mechanisms by which certain diuretics disrupt fuel metabolism and contribute to metabolic disturbances.

Comparison of Cardiovascular Outcomes Between Chlorthalidone and Hydrochlorothiazide in Hypertensive Patients

Chlorthalidone (CLTD) and hydrochlorothiazide (HCTZ) are widely used thiazide diuretics for hypertension management. This study aimed to evaluate and compare the cardiovascular outcomes of patients treated with CLTD versus HCTZ. This multicenter, retrospective cohort study utilized data from the Korea University Medical Center, derived from electronic health records. A total of 14 257 hypertensive patients treated with either CLTD (n = 1920) or HCTZ (n = 12 337) were identified. Patients were matched 1:1 using propensity scores, resulting in 1606 patients in each treatment group. Demographic and clinical characteristics, incidence of major adverse cardiovascular events (MACE), and safety profiles were analyzed. Baseline characteristics after propensity score matching were well balanced between the two groups. The average age was 61.8 ± 14.6 years for CLTD users, with 59.3% being male. The 3-year MACE occurred in 1.2% of the CLTD group compared with 1.4% of the HCTZ group (hazard ratio 0.91, p = 0.77). For secondary outcomes, cardiovascular mortality was 0.2% in both groups (p = 0.92). Myocardial infarction occurred in 0.3% of CLTD users and 0.4% of HCTZ users (p = 0.65). The incidence of hypokalemia was 19.2% in the CLTD group versus 16.7% in the HCTZ group (p = 0.07). In conclusion, in hypertensive patients, CLTD and HCTZ showed comparable cardiovascular outcomes and safety profiles.

A Systematic Review of Baseline Characteristics of Patients With Successful Decongestion on Combination Diuretic Therapy in Acute Decompensated Heart Failure (ADHF)

Acute decompensated heart failure (ADHF) often necessitates combination diuretic therapy when patients develop resistance to loop diuretics alone. Understanding baseline characteristics predictive of successful decongestion is essential for tailoring treatment strategies. This systematic review aimed to identify baseline characteristics associated with successful decongestion in ADHF patients undergoing combination diuretic therapy and to evaluate the effectiveness and risks of these therapies. A systematic review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, with a literature search spanning 2019 to 2024 across PubMed and other databases. Studies included randomized controlled trials (RCTs) and clinical trials focusing on combination diuretic therapy, including thiazide diuretics and acetazolamide. Inclusion criteria emphasized studies reporting baseline characteristics and decongestion outcomes. From 43 initially identified articles, four studies met inclusion criteria. Combination diuretic therapy improved diuretic response and congestion resolution, with specific therapies such as metolazone, hydrochlorothiazide, and tolvaptan showing varying levels of effectiveness. Patients with lower baseline congestion scores, preserved renal function (estimated glomerular filtration rate (eGFR) ≥41 ± 20 mL/min/1.73m²), and higher ejection fractions (≥35%) were more likely to experience favorable outcomes. Risks such as renal impairment occurred more frequently in patients with pre-existing chronic kidney disease (CKD), highlighting the importance of careful monitoring. Notably, metolazone led to greater weight loss (e.g., -6 kg vs. -3 kg) and enhanced diuretic response (940 ± 149 mL/40 mg furosemide/day vs. 541 ± 314 mL). Combination diuretic therapy is effective for improving fluid management in resistant ADHF, but baseline patient characteristics significantly influence outcomes. This review provides novel insights into the role of individualized treatment strategies in optimizing therapy. Future research should focus on validating biomarkers, risk stratification tools, and promising but understudied combinations to improve safety and efficacy.

The utility of urine sodium-guided diuresis during acute decompensated heart failure

Diuresis to achieve decongestion is a central aim of therapy in patients hospitalized for acute decompensated heart failure (ADHF). While multiple approaches have been tried to achieve adequate decongestion rapidly while minimizing adverse effects, no single diuretic strategy has shown superiority, and there is a paucity of data and guidelines to utilize in making these decisions. Observational cohort studies have shown associations between urine sodium excretion and outcomes after hospitalization for ADHF. Urine chemistries (urine sodium ± urine creatinine) may guide diuretic titration during ADHF, and multiple randomized clinical trials have been designed to compare a strategy of urine chemistry-guided diuresis to usual care. This review will summarize current literature for diuretic monitoring and titration strategies, outline evidence gaps, and describe the recently completed and ongoing clinical trials to address these gaps in patients with ADHF with a particular focus on the utility of urine sodium-guided strategies.

Combinational Diuretics in Heart Failure

PURPOSE OF REVIEW

Diuretics are the cornerstone therapy for acute heart failure (HF) and congestion. Patients chronically exposed to loop diuretics may develop diuretic resistance as a consequence of nephron remodelling, and the combination of diuretics will be necessary to improve diuretic response and achieve decongestion. This review integrates data from recent research and offers a practical approach to current pharmacologic therapies to manage congestion in HF with a focus on combinational therapy.

RECENT FINDINGS

Until recently, combined diuretic treatment was based on observational studies and expert opinion. Recent evidence from clinical trials has shown that combined diuretic treatment can be started earlier without escalating the doses of loop diuretics with an adequate safety profile. Diuretic combination is a promising strategy for overcoming diuretic resistance in HF. Further studies aiming to get more insights into the pathophysiology of diuretic resistance and large clinical trials confirming the safety and efficacy over standard diuretics regimens are warranted.