Effects of thiazides and new findings on kidney stones and dysglycemic side effects.

Thiazide and thiazide-like diuretics (thiazides) belong to the most frequently prescribed drugs worldwide. By virtue of their natriuretic and vasodilating properties, thiazides effectively lower blood pressure and prevent adverse cardiovascular outcomes. In addition, through their unique characteristic of reducing urine calcium, thiazides are also widely employed for the prevention of kidney stone recurrence and reduction of bone fracture risk. Since their introduction into clinical medicine in the early 1960s, thiazides have been recognized for their association with metabolic side effects, particularly impaired glucose tolerance, and new-onset diabetes mellitus. Numerous hypotheses have been advanced to explain thiazide-induced glucose intolerance, yet underlying mechanisms remain poorly defined. Regrettably, the lack of understanding and unpredictability of these side effects has prompted numerous physicians to refrain from prescribing these effective, inexpensive, and widely accessible drugs. In this review, we outline the pharmacology and mechanism of action of thiazides, highlight recent advances in the understanding of thiazide-induced glucose intolerance, and provide an up-to-date discussion on the role of thiazides in kidney stone prevention.

Thiazide-associated hyponatremia in arterial hypertension patients: A nationwide population-based cohort study.

OBJECTIVE: Thiazides are the first-line treatment for hypertension, however, they have been associated with hospitalizations for thiazide-associated hyponatremia (TAH). The aim of this study was to evaluate the risk of TAH and other drug-associated hyponatremia in a Korean population. METHODS: The study used big data from the National Health Insurance Sharing Service of 1,943,345 adults treated for hypertension from January 2014 to December 2016. The participants were divided into two groups based on the use of thiazides. Cox proportional hazard models were used to identify independent risk factors for the occurrence of hyponatremia. RESULTS: The study found that hyponatremia-related hospitalizations were significantly higher in the thiazide group than the control group (2.19% vs. 1.45%). The risk increased further with concurrent use of other diuretics or desmopressin, and thiazide+spironolactone+desmopressin and hospitalization risk further increased (4.0 and 6.9 times). Multivariate analysis showed that hyponatremia occurrence increased with age, diabetes mellitus, depression, and thiazide use (hazard ratio = 1.436, p < 0.001). The thiazide group had better 6-year overall survival than the control group but had more fractures and hyponatremia. CONCLUSIONS: Thiazide use is associated with an increased risk of hyponatremia and related complications. However, the mortality rate decreased in those who received thiazides, suggesting that thiazide use itself is not harmful and may help decrease complications and improve prognosis with proper, cautious use in high-risk patients.

Thiazides for kidney stone recurrence prevention.

PURPOSE OF REVIEW: Kidney stones are the most common condition affecting the kidney, and characterized by a high rate of recurrence. Thiazide and thiazide-like diuretics (thiazides) are commonly prescribed to prevent the recurrence of kidney stones. This review offers a comprehensive up-to-date assessment of the evidence supporting the use of thiazides for kidney stone recurrence prevention, highlights potential harms associated with treatment, and identifies areas of knowledge that require further investigation. RECENT FINDINGS: The clinical routine to prescribe thiazides for kidney stone prevention has recently been challenged by the findings of the large NOSTONE trial that failed to show superiority of hydrochlorothiazide at doses up to 50 mg daily over placebo in preventing a composite of clinical or radiological recurrence in patients at high risk of recurrence. Yet, adverse events such as new onset diabetes mellitus and gout were more common in patients receiving hydrochlorothiazide compared to placebo. As demonstrated by a novel meta-analysis presented in this review encompassing all randomized placebo-controlled trials with thiazide monotherapy, current trial evidence does not indicate that thiazide monotherapy is significantly better than placebo in preventing kidney stone recurrence. SUMMARY: Given the limited efficacy and possible adverse effects, we advocate for a restrictive use of thiazides for kidney stone recurrence prevention. Clearly, there remains a high unmet medical need for effective, targeted therapies to prevent recurrence of kidney stones.

Prescribing cascades of antigout medications from thiazide diuretics in gout-naïve hypertensive adults receiving first-line pharmacological management.

Prescribing cascade is a significant clinical problem but is often overlooked. We explore the incidence of the prescribing cascades of antigout medications related to thiazide treatment in gout-naïve hypertensive adults newly exposed to the pharmacological treatment. This population-based, retrospective cohort study used the Taiwan National Health Insurance Registry Database. Gout-naïve hypertensive adults who were newly dispensed first-line antihypertensive drugs between January 1, 2000, and December 31, 2016, were enrolled. Patients were divided into the thiazide group (n = 4192) and the non-thiazide group (n = 81,083). The non-thiazide group included patients who received an angiotensin-converting enzyme inhibitor, angiotensin II receptor blocker, calcium channel blocker, or beta-blocker. The study utilized propensity score matching and multivariable Cox regression models to investigate the prescribing cascade of antigout agents following antihypertensive treatment, adjusting for factors like age, sex, comorbidities, and concurrent medications. After propensity score matching, each group consisted of 4045 patients, with the thiazide group exhibiting a higher risk of being prescribed antigout medications across different time intervals post-treatment initiation. Specifically, adjusted hazard ratios (aHRs) for the thiazide group were 2.23, 2.07, and 2.41 for < 30 days, 31-180 days, and > 180 days, respectively, indicating a sustained and significant risk over time. Comparative analyses revealed thiazide diuretics were associated with a higher risk of antigout medication prescriptions compared to other antihypertensive classes, particularly evident after 180 days. Subgroup analyses across various demographics and comorbidities consistently showed an increased risk in the thiazide cohort. Gout-naïve hypertensive adults newly dispensed thiazide had a higher risk of subsequently adding antigout agents than those taking other first-line antihypertensive medications. The awareness and interruption of these prescribing cascades are critical to improving patient safety.

Comparative safety and effectiveness of angiotensin converting enzyme inhibitors and thiazides and thiazide-like diuretics under strict monotherapy.

Previous work comparing safety and effectiveness outcomes for new initiators of angiotensin converting-enzyme inhibitors (ACEi) and thiazides demonstrated more favorable outcomes for thiazides, although cohort definitions allowed for addition of a second antihypertensive medication after a week of monotherapy. Here, we modify the monotherapy definition, imposing exit from cohorts upon addition of another antihypertensive medication. We determine hazard ratios (HR) for 55 safety and effectiveness outcomes over six databases and compare results to earlier findings. We find, for all primary outcomes, statistically significant differences in effectiveness between ACEi and thiazides were not replicated (HRs: 1.11, 1.06, 1.12 for acute myocardial infarction, hospitalization with heart failure and stroke, respectively). While statistical significance is similarly lost for several safety outcomes, the safety profile of thiazides remains more favorable. Our results indicate a less striking difference in effectiveness of thiazides compared to ACEi and reflect some sensitivity to the monotherapy cohort definition modification.

[Thiazid diuretics : some useful considerations in clinical practice]. / Diurétiques thiazidiques. Quelques considérations utiles en pratique clinique.

Thiazide diuretics are an essential part of the treatment of hypertension, which affects nearly a third of the world's population. Hydrochlorothiazide is the most widely used member of this class, due to its long availability on the market and the many combinations available with other substances. Other analogues of this class exist, with notable advantages from a clinical point of view, recognized under the name of thiazide-like. This article reviews some of the considerations in clinical practice concerning the different types of thiazides currently available in Switzerland.

Les diurétiques thiazidiques font partie des traitements de premier choix dans la prise en charge de l'hypertension artérielle, touchant près d'un tiers de la population mondiale. L'hydrochlorothiazide est le représentant de cette classe médicamenteuse le plus utilisé dans les combinaisons antihypertensives en Suisse. D'autres analogues de cette classe existent sur le marché, avec des avantages notables du point de vue clinique, reconnus sous la dénomination de thiazides-like. Le choix de l'utilisation d'un diurétique thiazidique repose avant tout sur les indications et les contre-indications relatives à cette classe. Cet article propose une revue de quelques considérations en pratique clinique sur les différents types de thiazides actuellement disponibles en Suisse.

Diferencias en función del sexo en las características clínicas y resultados del ensayo clínico CLOROTIC (combinación de diuréticos de asa con tiazidas en la insuficiencia cardiaca descompensada) / Sex differences in clinical characteristics and outcomes in the CLOROTIC (combining loop with thiazide diuretics for decompensated heart failure) trial

ObjetivoEvaluar si existen diferencias en los resultados del ensayo clínico CLOROTIC según el sexo. Métodos Subanálisis del ensayo CLOROTIC, que evaluó la eficacia y la seguridad de añadir hidroclorotiazida (HCTZ) o placebo a furosemida intravenosa en pacientes con insuficiencia cardiaca aguda (ICA). Los resultados primarios y secundarios incluyeron cambios en el peso y la disnea a las 72 y 96horas, medidas de la respuesta diurética y la mortalidad y reingresos a los 30 y 90días. Se evaluó la influencia del sexo en los resultados primarios y secundarios y de seguridad. Resultados De los 230 pacientes incluidos, 111 (48%) eran mujeres, que tenían más edad y valores más elevados de fracción de eyección ventricular izquierda. Los hombres tenían más cardiopatía isquémica, enfermedad pulmonar obstructiva crónica y mayor valor de péptidos natriuréticos. La adición de HCTZ a furosemida se asoció con una mayor pérdida de peso a las 72/96horas y mejor respuesta diurética a las 24horas en comparación con el placebo, sin diferencias significativas según el sexo (ningún valor de p para la interacción fue significativo). El deterioro de la función renal fue más frecuente en mujeres (OR: 8,68; IC95%: 3,41-24,63) que en varones (OR: 2,5; IC95%: 0,99-4,87), p=0,027. No hubo diferencias en la mortalidad ni en los reingresos a los 30/90días. Conclusión La adición de HCTZ a furosemida intravenosa es una estrategia eficaz para mejorar la respuesta diurética en la ICA sin diferencias según el sexo. Sin embargo, el deterioro de la función renal es más frecuente en las mujeres. (AU)

Aims The addition of hydrochlorothiazide (HCTZ) to furosemide improved the diuretic response in patients with acute heart failure (AHF) in the CLOROTIC trial. Our aim was to evaluate if there were differences in clinical characteristics and outcomes according to sex. Methods This is a post hoc analysis of the CLOROTIC trial, including 230 patients with AHF randomized to receive HCTZ or placebo in addition to an intravenous furosemide regimen. The primary and secondary outcomes included changes in weight and patient-reported dyspnoea 72 and 96h after randomization, metrics of diuretic response and mortality/rehospitalizations at 30 and 90days. The influence of sex on primary, secondary and safety outcomes was evaluated. Results One hundred and eleven (48%) women were included in the study. Women were older and had higher values of left ventricular ejection fraction. Men had more ischemic cardiomyopathy and chronic obstructive pulmonary disease and higher values of natriuretic peptides. The addition of HCTZ to furosemide was associated to a greatest weight loss at 72/96h, better metrics of diuretic response and higher 24-h diuresis compared to placebo without significant differences according to sex (all P-values for interaction were not significant). Worsening renal function occurred more frequently in women (OR: 8.68; 95%CI: 3.41-24.63) than men (OR: 2.5; 95%CI: 0.99-4.87), P=.027. There were no differences in mortality or rehospitalizations at 30/90days. Conclusion Adding HCTZ to intravenous furosemide is an effective strategy to improve diuretic response in AHF with no difference according to sex, but worsening renal function was more frequent in women. (AU)

[Change in the prevention of kidney stones]. / Lithiase rénale, un changement de paradigme?

Kidney stone is one of the most frequent disorders of the urinary tract. Once the stone has passed, the management should be oriented on prevention. If changes in lifestyle and diet should be implemented in a true therapeutic education of the patient, prescription of drugs has been recently challenged by the NOSTONE trial. This randomized controlled trial did not show any benefit of hydrochlorothiazide in the prevention of recurrence of kidney stone event in patients with calcium-containing stone. Therefore, prescription of thiazide in the sole purpose of decreasing kidney stone recurrence should be limited and the risk/benefit of this treatment should be carefully balanced for each case.

La maladie rénale lithiasique est une des affections les plus fréquentes de l'axe urinaire. Une fois l'expulsion du calcul obtenue, la prise en charge est orientée sur la prévention. Si les modifications diététiques et comportementales doivent être implémentées dans le cadre d'une véritable éducation thérapeutique, la prescription de traitements médicamenteux préventifs est remise en question par l'étude NOSTONE. Cette étude randomisée contrôlée n'a pas montré de bénéfice de l'hydrochlorothiazide dans la prévention de la récidive des calculs à contenu calcique. Dès lors, la prescription de thiazide en monothérapie dans le but de diminuer les récidives de calculs doit être limitée et le risque/bénéfice soigneusement évalué dans chaque cas.

Circulating microRNA Biomarkers of Thiazide Response in Hypertension.

BACKGROUND: Thiazide diuretics are the second most frequently prescribed class of antihypertensives, but up to 50% of patients with hypertension have minimal antihypertensive response to thiazides. We explored circulating microRNAs (miRNAs) in search of predictive biomarkers of thiazide response. METHODS AND RESULTS: We profiled 754 miRNAs in baseline plasma samples of 36 hypertensive European American adults treated with hydrochlorothiazide, categorized into responders (n=18) and nonresponders (n=18) on the basis of diastolic blood pressure response to hydrochlorothiazide. miRNAs with ≥2.5-fold differential expression between responders and nonresponders were considered for validation in 3 cohorts (n=50 each): hydrochlorothiazide-treated European Americans, chlorthalidone-treated European Americans, and hydrochlorothiazide-treated Black individuals. Different blood pressure phenotypes including categorical (responder versus nonresponder) and continuous diastolic blood pressure and systolic blood pressure were tested for association with the candidate miRNA expression using multivariate regression analyses adjusting for age, sex, and baseline blood pressure. After quality control, 74 miRNAs were available for screening, 19 of which were considered for validation. In the validation cohort, miR-193b-3p and 30d-5p showed significant associations with continuous SBP or diastolic blood pressure response or both, to hydrochlorothiazide in European Americans at Benjamini-Hochberg adjusted P<0.05. In the combined analysis of validation cohorts, let-7g (odds ratio, 0.6 [95% CI, 0.4-0.8]), miR-142-3p (odds ratio, 1.1 [95% CI, 1.0, 1.2]), and miR-423-5p (odds ratio, 0.7 [95% CI, 0.5-0.9]) associated with categorical diastolic blood pressure response at Benjamini-Hochberg adjusted P<0.05. Predicted target genes of the 5 miRNAs were mapped to key hypertension pathways: lysine degradation, fatty acid biosynthesis, and metabolism. CONCLUSIONS: The above identified circulating miRNAs may have a potential for clinical use as biomarkers for thiazide diuretic selection in hypertension. REGISTRATION: URL: ClinicalTrials.gov. Unique identifiers: NCT00246519, NCT01203852, NCT00005520.

Diferencias en función del sexo en las características clínicas y resultados del ensayo clínico CLOROTIC (combinación de diuréticos de asa con tiazidas en la insuficiencia cardiaca descompensada) / Sex differences in clinical characteristics and outcomes in the CLOROTIC (combining loop with thiazide diuretics for decompensated heart failure) trial

ObjetivoEvaluar si existen diferencias en los resultados del ensayo clínico CLOROTIC según el sexo. Métodos Subanálisis del ensayo CLOROTIC, que evaluó la eficacia y la seguridad de añadir hidroclorotiazida (HCTZ) o placebo a furosemida intravenosa en pacientes con insuficiencia cardiaca aguda (ICA). Los resultados primarios y secundarios incluyeron cambios en el peso y la disnea a las 72 y 96horas, medidas de la respuesta diurética y la mortalidad y reingresos a los 30 y 90días. Se evaluó la influencia del sexo en los resultados primarios y secundarios y de seguridad. Resultados De los 230 pacientes incluidos, 111 (48%) eran mujeres, que tenían más edad y valores más elevados de fracción de eyección ventricular izquierda. Los hombres tenían más cardiopatía isquémica, enfermedad pulmonar obstructiva crónica y mayor valor de péptidos natriuréticos. La adición de HCTZ a furosemida se asoció con una mayor pérdida de peso a las 72/96horas y mejor respuesta diurética a las 24horas en comparación con el placebo, sin diferencias significativas según el sexo (ningún valor de p para la interacción fue significativo). El deterioro de la función renal fue más frecuente en mujeres (OR: 8,68; IC95%: 3,41-24,63) que en varones (OR: 2,5; IC95%: 0,99-4,87), p=0,027. No hubo diferencias en la mortalidad ni en los reingresos a los 30/90días. Conclusión La adición de HCTZ a furosemida intravenosa es una estrategia eficaz para mejorar la respuesta diurética en la ICA sin diferencias según el sexo. Sin embargo, el deterioro de la función renal es más frecuente en las mujeres. (AU)

Aims The addition of hydrochlorothiazide (HCTZ) to furosemide improved the diuretic response in patients with acute heart failure (AHF) in the CLOROTIC trial. Our aim was to evaluate if there were differences in clinical characteristics and outcomes according to sex. Methods This is a post hoc analysis of the CLOROTIC trial, including 230 patients with AHF randomized to receive HCTZ or placebo in addition to an intravenous furosemide regimen. The primary and secondary outcomes included changes in weight and patient-reported dyspnoea 72 and 96h after randomization, metrics of diuretic response and mortality/rehospitalizations at 30 and 90days. The influence of sex on primary, secondary and safety outcomes was evaluated. Results One hundred and eleven (48%) women were included in the study. Women were older and had higher values of left ventricular ejection fraction. Men had more ischemic cardiomyopathy and chronic obstructive pulmonary disease and higher values of natriuretic peptides. The addition of HCTZ to furosemide was associated to a greatest weight loss at 72/96h, better metrics of diuretic response and higher 24-h diuresis compared to placebo without significant differences according to sex (all P-values for interaction were not significant). Worsening renal function occurred more frequently in women (OR: 8.68; 95%CI: 3.41-24.63) than men (OR: 2.5; 95%CI: 0.99-4.87), P=.027. There were no differences in mortality or rehospitalizations at 30/90days. Conclusion Adding HCTZ to intravenous furosemide is an effective strategy to improve diuretic response in AHF with no difference according to sex, but worsening renal function was more frequent in women. (AU)

Kinase Scaffold Cab39 Is Necessary for Phospho-Activation of the Thiazide-Sensitive NCC.

BACKGROUND: Potassium regulates the WNK (with no lysine kinase)-SPAK (STE20/SPS1-related proline/alanine-rich kinase) signaling axis, which in turn controls the phosphorylation and activation of the distal convoluted tubule thiazide-sensitive NCC (sodium-chloride cotransporter) for sodium-potassium balance. Although their roles in the kidney have not been investigated, it has been postulated that Cab39 (calcium-binding protein 39) or Cab39l (Cab39-like) is required for SPAK/OSR1 (oxidative stress response 1) activation. This study demonstrates how they control the WNK-SPAK/OSR1-NCC pathway. METHODS: We created a global knockout of Cab39l and a tamoxifen-inducible, NCC-driven, Cab39 knockout. The 2 lines were crossed to generate Cab39-DKO (Cab39 double knockout) animals. Mice were studied under control and low-potassium diet, which activates WNK-SPAK/OSR1-NCC phosphorylation. Western blots were used to assess the expression and phosphorylation of proteins. Blood and urine electrolytes were measured to test for compromised NCC function. Immunofluorescence studies were conducted to localize SPAK and OSR1. RESULTS: Both Cab39l and Cab39 are expressed in distal convoluted tubule, and only the elimination of both leads to a striking absence of NCC phosphorylation. Cab39-DKO mice exhibited a loss-of-NCC function, like in Gitelman syndrome. In contrast to the apical membrane colocalization of SPAK with NCC in wild-type mice, SPAK and OSR1 become confined to intracellular puncta in the Cab39-DKO mice. CONCLUSIONS: In the absence of Cab39 proteins, NCC cannot be phosphorylated, resulting in a Gitelman-like phenotype. Cab39 proteins function to localize SPAK at the apical membrane with NCC, reminiscent of the Cab39 yeast homolog function, translocating kinases during cytokinesis.

From Fish Physiology to Human Disease: The Discovery of the NCC, NKCC2, and the Cation-Coupled Chloride Cotransporters.

The renal Na-K-2Cl and Na-Cl cotransporters are the major salt reabsorption pathways in the thick ascending limb of Henle loop and the distal convoluted tubule, respectively. These transporters are the target of the loop and thiazide type diuretics extensively used in the world for the treatment of edematous states and arterial hypertension. The diuretics appeared in the market many years before the salt transport systems were discovered. The evolving of the knowledge and the cloning of the genes encoding the Na-K-2Cl and Na-Cl cotransporters were possible thanks to the study of marine species. This work presents the history of how we came to know the mechanisms for the loop and thiazide type diuretics actions, the use of marine species in the cloning process of these cotransporters and therefore in the whole solute carrier cotransproters 12 (SLC12) family of electroneutral cation chloride cotransporters, and the disease associated with each member of the family.

Fall risk and cardiovascular outcomes of first-line antihypertensive medications in nursing home residents.

BACKGROUND: Little evidence exists about the comparative effects of first-line antihypertensive medications (i.e., renin-angiotensin-aldosterone converting enzyme inhibitors (RAASi), amlodipine, or thiazide diuretics) in older adults with limited life expectancy. We compared the rates of injurious falls and short-term cardiovascular events between different first-line antihypertensive medication classes in adults receiving care in nursing homes (NH). METHODS: This was a retrospective cohort of Medicare fee-for-service beneficiaries receiving care in NHs. Patients newly dispensed first-line antihypertensive medications were identified using Part D claims (2015-2018) and linked with clinical assessments (i.e., Minimum Data Set). Fall-related injuries (FRI), hip fractures, and major adverse cardiac events (MACE) outcomes were identified using hospitalization claims. Patients were followed from the date of antihypertensive dispensing until the occurrence of outcomes, death, disenrollment, or 6-month follow-up. Inverse-probability-of-treatment-weighted (IPTW) cause-specific hazards regression models were used to compare outcomes between patients who were new users of RAASi, amlodipine, or thiazides. RESULTS: Our cohort included 16,504 antihypertensive users (RAASi, n = 9574; amlodipine, n = 5049; thiazide, n = 1881). Mean age was 83.5 years (± 8.2), 70.6% were female, and 17.2% were non-white race. During a mean follow-up of 5.3 months, 326 patients (2.0%) experienced an injurious fall, 1590 (9.6%) experienced MACE, and 2123 patients (12.9%) died. The intention-to-treat IPTW hazard ratio (HR) for injurious falls for amlodipine (vs RAASi) use was 0.85 (95% confidence interval (CI) 0.66-1.08) and for thiazides (vs RAASi) was 1.22 (95% CI 0.88-1.66). The rates of MACE were similar between those taking anti-hypertensive medications. Thiazides were discontinued more often than other classes; however, inferences were largely unchanged in as-treated analyses. Subgroup analyses were generally consistent. CONCLUSIONS: Older adults with limited life expectancy experience similar rates of injurious falls and short-term cardiovascular events after initiating any of the first-line antihypertensive medications.

Dysregulation of the WNK4-SPAK/OSR1 pathway has a minor effect on baseline NKCC2 phosphorylation.

The with-no-lysine kinase 4 (WNK4)-sterile 20/SPS-1-related proline/alanine-rich kinase (SPAK)/oxidative stress-responsive kinase 1 (OSR1) pathway mediates activating phosphorylation of the furosemide-sensitive Na+-K+-2Cl- cotransporter (NKCC2) and the thiazide-sensitive NaCl cotransporter (NCC). The commonly used pT96/pT101-pNKCC2 antibody cross-reacts with pT53-NCC in mice on the C57BL/6 background due to a five amino acid deletion. We generated a new C57BL/6-specific pNKCC2 antibody (anti-pT96-NKCC2) and tested the hypothesis that the WNK4-SPAK/OSR1 pathway strongly regulates the phosphorylation of NCC but not NKCC2. In C57BL/6 mice, anti-pT96-NKCC2 detected pNKCC2 and did not cross-react with NCC. Abundances of pT96-NKCC2 and pT53-NCC were evaluated in Wnk4-/-, Osr1-/-, Spak-/-, and Osr1-/-/Spak-/- mice and in several models of the disease familial hyperkalemic hypertension (FHHt) in which the CUL3-KLHL3 ubiquitin ligase complex that promotes WNK4 degradation is dysregulated (Cul3+/-/Δ9, Klhl3-/-, and Klhl3R528H/R528H). All mice were on the C57BL/6 background. In Wnk4-/- mice, pT53-NCC was almost absent but pT96-NKCC2 was only slightly lower. pT53-NCC was almost absent in Spak-/- and Osr1-/-/Spak-/- mice, but pT96-NKCC2 abundance did not differ from controls. pT96-NKCC2/total NKCC2 was slightly lower in Osr1-/- and Osr1-/-/Spak-/- mice. WNK4 expression colocalized not only with NCC but also with NKCC2 in Klhl3-/- mice, but pT96-NKCC2 abundance was unchanged. Consistent with this, furosemide-induced urinary Na+ excretion following thiazide treatment was similar between Klhl3-/- and controls. pT96-NKCC2 abundance was also unchanged in the other FHHt mouse models. Our data show that disruption of the WNK4-SPAK/OSR1 pathway only mildly affects NKCC2 phosphorylation, suggesting a role for other kinases in NKCC2 activation. In FHHt models NKCC2 phosphorylation is unchanged despite higher WNK4 abundance, explaining the thiazide sensitivity of FHHt.NEW & NOTEWORTHY The renal cation cotransporters NCC and NKCC2 are activated following phosphorylation mediated by the WNK4-SPAK/OSR1 pathway. While disruption of this pathway strongly affects NCC activity, effects on NKCC2 activity are unclear since the commonly used phospho-NKCC2 antibody was recently reported to cross-react with phospho-NCC in mice on the C57BL/6 background. Using a new phospho-NKCC2 antibody specific for C57BL/6, we show that inhibition or activation of the WNK4-SPAK/OSR1 pathway in mice only mildly affects NKCC2 phosphorylation.

Diuretic Tolerance to Repeated-Dose Furosemide in Infants Born Very Preterm with Bronchopulmonary Dysplasia.

OBJECTIVES: To assess the presence and timing of furosemide diuretic tolerance in infants with bronchopulmonary dysplasia (BPD), and to determine if tolerance is modified by thiazide co-administration. STUDY DESIGN: We performed a retrospective cohort study among infants born very preterm with BPD exposed to repeated-dose furosemide for 72 hours, measuring net fluid balance (total intake minus total output) as a surrogate of diuresis in the 3 days before and after exposure. The primary comparison was the difference in fluid balance between the first and third 24 hours of furosemide exposure. We fit a general linear model for within-subject repeated measures of fluid balance over time, with thiazide co-administration as an interaction variable. Secondary analyses included an evaluation of weight trajectories over time. RESULTS: In 83 infants, median fluid balance ranged between + 43.6 and + 52.7 ml/kg/d in the 3 days prior to furosemide exposure. Fluid balance decreased to a median of + 29.1 ml/kg/d in the first 24 hours after furosemide, but then increased to +47.5 ml/kg/d by the third 24-hour interval, consistent with tolerance (P < .001). Thiazides did not modify the change in fluid balance during furosemide exposure for any time-period. Weight decreased significantly in the first 24 hours after furosemide and increased thereafter (P < .001). CONCLUSIONS: The net fluid balance response to furosemide decreases rapidly during repeated-dose exposures in infants with BPD, consistent with diuretic tolerance. Clinicians should consider this finding in the context of an infant's therapeutic goals. Further research efforts to identify safe and effective furosemide dosage strategies are needed.

[Are thiazide diuretics ineffective with a glomerular filtration rate lower than 50 ml/min?] / Thiaziddiuretika unwirksam bei einer glomerulären Filtrationsrate kleiner als 50 ml/min?

Many treatment guidelines do not recommend the use of thiazide diuretics or thiazide-like diuretics in patients with impaired kidney function. The rationale is a presumed lack of efficacy of these diuretics in cases of a reduced glomerular filtration rate (GFR); however, this paradigm could not be verified in recent studies. Thiazide diuretics and thiazide-like diuretics are also effective in patients with substantially reduced GFR, which pertains to natriuresis, correction of volume overload and lowering of blood pressure; however, in patients with chronic kidney disease loop diuretics can control volume overload more rapidly. Particularly effective is the combination of loop diuretics with thiazide diuretics or thiazide-like diuretics in patients with markedly limited GFR. Therefore, thiazide diuretics and thiazide-like diuretics should also be prescribed even for patients with higher grade impairments of kidney function (chronic kidney disease in stages 3-5), except for anuric patients where they are ineffective.

Comparison of Class-Specific Side Effects Across Preventative Pharmacologic Therapies for Kidney Stone Disease.

INTRODUCTION: Clinical guidelines recommend monitoring for metabolic derangements while on preventive pharmacologic therapy for kidney stone disease. The study objective was to compare the frequency of side effects among patients receiving alkali citrate, thiazides, and allopurinol. METHODS: Using claims data from working-age adults with kidney stone disease (2008-2019), we identified those with a new prescription for alkali citrate, thiazide, or allopurinol within 12 months after their index stone-related diagnosis or procedure. We fit multivariable logistic regression models, adjusting for cohort characteristics like comorbid illness and medication adherence, to estimate 2-year measured frequencies of claims-based outcomes of acute kidney injury, falls/hip fracture, gastritis, abnormal liver function tests/hepatitis, hypercalcemia, hyperglycemia/diabetes, hyperkalemia, hypokalemia, hyponatremia, and hypotension. RESULTS: Our cohort consisted of 1776 (34%), 2767 (53%), and 677 (13%) patients prescribed alkali citrate, thiazides, or allopurinol, respectively. Comparing unadjusted rates of incident diagnoses, thiazides compared to alkali citrate and allopurinol were associated with the highest rates of hypercalcemia (2.3% vs 1.5% and 1.0%, respectively, P = .04), hypokalemia (6% vs 3% and 2%, respectively, P < .01), and hyperglycemia/diabetes (17% vs 11% and 16%, respectively, P < .01). No other differences with the other outcomes were significant. In adjusted analyses, compared to alkali citrate, thiazides were associated with a higher odds of hypokalemia (OR=2.01, 95% CI 1.44-2.81) and hyperglycemia/diabetes (OR=1.52, 95% CI 1.26-1.83), while allopurinol was associated with a higher odds of hyperglycemia/diabetes (OR=1.34, 95% CI 1.02-1.75). CONCLUSIONS: These data provide evidence to support clinical guidelines that recommend periodic serum testing to assess for adverse effects from preventive pharmacologic therapy.

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.

Discovery of a Novel Benzothiadiazine-Based Selective Aldose Reductase Inhibitor as Potential Therapy for Diabetic Peripheral Neuropathy.

Aldose reductase 2 (ALR2), an activated enzyme in the polyol pathway by hyperglycemia, has long been recognized as one of the most promising targets for complications of diabetes, especially in diabetic peripheral neuropathy (DPN). However, many of the ALR2 inhibitors have shown serious side effects due to poor selectivity over aldehyde reductase (ALR1). Herein, we describe the discovery of a series of benzothiadiazine acetic acid derivatives as potent and selective inhibitors against ALR2 and evaluation of their anti-DPN activities in vivo. Compound 15c, carrying a carbonyl group at the 3-position of the thiadiazine ring, showed high potent inhibition against ALR2 (IC50 = 33.19 nmol/L) and ∼16,109-fold selectivity for ALR2 over ALR1. Cytotoxicity assays ensured the primary biosafety of 15c. Further pharmacokinetic assay in rats indicated that 15c had a good pharmacokinetic feature (t1/2 = 5.60 h, area under the plasma concentration time curve [AUC(0-t)] = 598.57 ± 216.5 µg/mL * h), which was superior to epalrestat (t1/2 = 2.23 h, AUC[0-t] = 20.43 ± 3.7 µg/mL * h). Finally, in a streptozotocin-induced diabetic rat model, 15c significantly increased the nerve conduction velocities of impaired sensory and motor nerves, achieved potent inhibition of d-sorbitol production in the sciatic nerves, and significantly increased the paw withdrawal mechanical threshold. By combining the above investigations, we propose that 15c might represent a promising lead compound for the discovery of an antidiabetic peripheral neuropathy drug.