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1.
N Engl J Med ; 389(3): 228-238, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37467498

RESUMO

BACKGROUND: Angiotensinogen is the sole precursor of angiotensin peptides and has a key role in the pathogenesis of hypertension. Zilebesiran, an investigational RNA interference therapeutic agent with a prolonged duration of action, inhibits hepatic angiotensinogen synthesis. METHODS: In this phase 1 study, patients with hypertension were randomly assigned in a 2:1 ratio to receive either a single ascending subcutaneous dose of zilebesiran (10, 25, 50, 100, 200, 400, or 800 mg) or placebo and were followed for 24 weeks (Part A). Part B assessed the effect of the 800-mg dose of zilebesiran on blood pressure under low- or high-salt diet conditions, and Part E the effect of that dose when coadministered with irbesartan. End points included safety, pharmacokinetic and pharmacodynamic characteristics, and the change from baseline in systolic and diastolic blood pressure, as measured by 24-hour ambulatory blood-pressure monitoring. RESULTS: Of 107 patients enrolled, 5 had mild, transient injection-site reactions. There were no reports of hypotension, hyperkalemia, or worsening of renal function resulting in medical intervention. In Part A, patients receiving zilebesiran had decreases in serum angiotensinogen levels that were correlated with the administered dose (r = -0.56 at week 8; 95% confidence interval, -0.69 to -0.39). Single doses of zilebesiran (≥200 mg) were associated with decreases in systolic blood pressure (>10 mm Hg) and diastolic blood pressure (>5 mm Hg) by week 8; these changes were consistent throughout the diurnal cycle and were sustained at 24 weeks. Results from Parts B and E were consistent with attenuation of the effect on blood pressure by a high-salt diet and with an augmented effect through coadministration with irbesartan, respectively. CONCLUSIONS: Dose-dependent decreases in serum angiotensinogen levels and 24-hour ambulatory blood pressure were sustained for up to 24 weeks after a single subcutaneous dose of zilebesiran of 200 mg or more; mild injection-site reactions were observed. (Funded by Alnylam Pharmaceuticals; ClinicalTrials.gov number, NCT03934307; EudraCT number, 2019-000129-39.).


Assuntos
Angiotensinogênio , Anti-Hipertensivos , Hipertensão , Humanos , Angiotensinogênio/sangue , Angiotensinogênio/metabolismo , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/efeitos adversos , Anti-Hipertensivos/farmacocinética , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Monitorização Ambulatorial da Pressão Arterial , Método Duplo-Cego , Hipertensão/sangue , Hipertensão/tratamento farmacológico , Hipertensão/etiologia , Hipertensão/metabolismo , Irbesartana/administração & dosagem , Irbesartana/efeitos adversos , Irbesartana/farmacocinética , Irbesartana/uso terapêutico , Interferência de RNA , Tetrazóis , Dieta , Injeções Subcutâneas
2.
Opt Lett ; 49(3): 690-693, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300091

RESUMO

We demonstrate a broadband acousto-optic notch filter based on a tubular-lattice hollow-core fiber for the first time to our knowledge. The guided optical modes are modulated by acoustically induced dynamic long-period gratings along the fiber. The device is fabricated employing a short interaction length (7.7 cm) and low drive voltages (10 V). Modulated spectral bands with 20 nm half-width and maximum depths greater than 60% are achieved. The resonant notch wavelength is tuned from 743 to 1355 nm (612 nm span) by changing the frequency of the electrical signal. The results indicate a broader tuning range compared to previous studies using standard and hollow-core fibers. It further reveals unique properties for reconfigurable spectral filters and fiber lasers, pointing to the fast switching and highly efficient modulation of all-fiber photonic devices.

3.
Circulation ; 145(6): 416-423, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35130054

RESUMO

BACKGROUND: Acetaminophen is widely used as first-line therapy for chronic pain because of its perceived safety and the assumption that, unlike nonsteroidal anti-inflammatory drugs, it has little or no effect on blood pressure (BP). Although observational studies suggest that acetaminophen may increase BP, clinical trials are lacking. We, therefore, studied the effects of regular acetaminophen dosing on BP in individuals with hypertension. METHODS: In this double-blind, placebo-controlled, crossover study, 110 individuals were randomized to receive 1 g acetaminophen 4× daily or matched placebo for 2 weeks followed by a 2-week washout period before crossing over to the alternate treatment. At the beginning and end of each treatment period, 24-hour ambulatory BPs were measured. The primary outcome was a comparison of the change in mean daytime systolic BP from baseline to end of treatment between the placebo and acetaminophen arms. RESULTS: One-hundred three patients completed both arms of the study. Regular acetaminophen, compared with placebo, resulted in a significant increase in mean daytime systolic BP (132.8±10.5 to 136.5±10.1 mm Hg [acetaminophen] vs 133.9±10.3 to 132.5±9.9 mm Hg [placebo]; P<0.0001) with a placebo-corrected increase of 4.7 mm Hg (95% CI, 2.9-6.6) and mean daytime diastolic BP (81.2±8.0 to 82.1±7.8 mm Hg [acetaminophen] vs 81.7±7.9 to 80.9±7.8 mm Hg [placebo]; P=0.005) with a placebo-corrected increase of 1.6 mm Hg (95% CI, 0.5-2.7). Similar findings were seen for 24-hour ambulatory and clinic BPs. CONCLUSIONS: Regular daily intake of 4 g acetaminophen increases systolic BP in individuals with hypertension by ≈5 mm Hg when compared with placebo; this increases cardiovascular risk and calls into question the safety of regular acetaminophen use in this situation. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01997112. URL: https://www.clinicaltrialsregister.eu; Unique identifier: 2013-003204-40.


Assuntos
Acetaminofen/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Acetaminofen/farmacologia , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Lancet ; 400(10361): 1417-1425, 2022 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-36240838

RESUMO

BACKGROUND: Studies have suggested that evening dosing with antihypertensive therapy might have better outcomes than morning dosing. The Treatment in Morning versus Evening (TIME) study aimed to investigate whether evening dosing of usual antihypertensive medication improves major cardiovascular outcomes compared with morning dosing in patients with hypertension. METHODS: The TIME study is a prospective, pragmatic, decentralised, parallel-group study in the UK, that recruited adults (aged ≥18 years) with hypertension and taking at least one antihypertensive medication. Eligible participants were randomly assigned (1:1), without restriction, stratification, or minimisation, to take all of their usual antihypertensive medications in either the morning (0600-1000 h) or in the evening (2000-0000 h). Participants were followed up for the composite primary endpoint of vascular death or hospitalisation for non-fatal myocardial infarction or non-fatal stroke. Endpoints were identified by participant report or record linkage to National Health Service datasets and were adjudicated by a committee masked to treatment allocation. The primary endpoint was assessed as the time to first occurrence of an event in the intention-to-treat population (ie, all participants randomly assigned to a treatment group). Safety was assessed in all participants who submitted at least one follow-up questionnaire. The study is registered with EudraCT (2011-001968-21) and ISRCTN (18157641), and is now complete. FINDINGS: Between Dec 17, 2011, and June 5, 2018, 24 610 individuals were screened and 21 104 were randomly assigned to evening (n=10 503) or morning (n=10 601) dosing groups. Mean age at study entry was 65·1 years (SD 9·3); 12 136 (57·5%) participants were men; 8968 (42·5%) were women; 19 101 (90·5%) were White; 98 (0·5%) were Black, African, Caribbean, or Black British (ethnicity was not reported by 1637 [7·8%] participants); and 2725 (13·0%) had a previous cardiovascular disease. By the end of study follow-up (March 31, 2021), median follow-up was 5·2 years (IQR 4·9-5·7), and 529 (5·0%) of 10 503 participants assigned to evening treatment and 318 (3·0%) of 10 601 assigned to morning treatment had withdrawn from all follow-up. A primary endpoint event occurred in 362 (3·4%) participants assigned to evening treatment (0·69 events [95% CI 0·62-0·76] per 100 patient-years) and 390 (3·7%) assigned to morning treatment (0·72 events [95% CI 0·65-0·79] per 100 patient-years; unadjusted hazard ratio 0·95 [95% CI 0·83-1·10]; p=0·53). No safety concerns were identified. INTERPRETATION: Evening dosing of usual antihypertensive medication was not different from morning dosing in terms of major cardiovascular outcomes. Patients can be advised that they can take their regular antihypertensive medications at a convenient time that minimises any undesirable effects. FUNDING: British Heart Foundation.


Assuntos
Hipertensão , Infarto do Miocárdio , Adulto , Masculino , Humanos , Feminino , Adolescente , Idoso , Anti-Hipertensivos/uso terapêutico , Estudos Prospectivos , Medicina Estatal , Estudos de Tempo e Movimento , Resultado do Tratamento , Hipertensão/induzido quimicamente , Infarto do Miocárdio/tratamento farmacológico , Reino Unido/epidemiologia
5.
Kidney Int ; 102(5): 1115-1126, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35998848

RESUMO

Cardiovascular disease is a complication of systemic inflammatory diseases including anti-neutrophil cytoplasm antibody-associated vasculitis (AAV). The mechanisms of cardiovascular morbidity in AAV are poorly understood, and risk-reduction strategies are lacking. Therefore, in a series of double-blind, randomized case-control forearm plethysmography and crossover systemic interventional studies, we examined arterial stiffness and endothelial function in patients with AAV in long-term disease remission and in matched healthy volunteers (32 each group). The primary outcome for the case-control study was the difference in endothelium-dependent vasodilation between health and AAV, and for the crossover study was the difference in pulse wave velocity (PWV) between treatment with placebo and selective endothelin-A receptor antagonism. Parallel in vitro studies of circulating monocytes and platelets explored mechanisms. Compared to healthy volunteers, patients with AAV had 30% reduced endothelium-dependent vasodilation and 50% reduced acute release of endothelial active tissue plasminogen activator (tPA), both significant in the case-control study. Patients with AAV had significantly increased arterial stiffness (PWV: 7.3 versus 6.4 m/s). Plasma endothelin-1 was two-fold higher in AAV and independently predicted PWV and tPA release. Compared to placebo, both selective endothelin-A and dual endothelin-A/B receptor blockade reduced PWV and increased tPA release in AAV in the crossover study. Mechanistically, patients with AAV had increased platelet activation, more platelet-monocyte aggregates, and altered monocyte endothelin receptor function, reflecting reduced endothelin-1 clearance. Patients with AAV in long-term remission have elevated cardiovascular risk and endothelin-1 contributes to this. Thus, our data support a role for endothelin-blockers to reduce cardiovascular risk by reducing arterial stiffness and increasing circulating tPA activity.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Doenças Cardiovasculares , Rigidez Vascular , Humanos , Ativador de Plasminogênio Tecidual , Fibrinólise , Análise de Onda de Pulso , Doenças Cardiovasculares/etiologia , Endotelina-1 , Estudos de Casos e Controles , Estudos Cross-Over , Fatores de Risco , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Fatores de Risco de Doenças Cardíacas , Receptores de Endotelina
6.
Curr Opin Nephrol Hypertens ; 30(4): 456-465, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33990507

RESUMO

PURPOSE OF REVIEW: To summarize new clinical findings of endothelin receptor antagonists (ERA) in various etiologies of kidney disease targeted in clinical trials. RECENT FINDINGS: Endothelin-1 is a multifunctional peptide with potential relevance to glomerular and tubulointerstitial kidney diseases. The phase 3 SONAR trial demonstrated a significant reduction in clinically relevant kidney outcomes for patients with diabetic kidney disease (DKD) after long-term treatment with the ERA, atrasentan, in addition to blockade of the renin-angiotensin-aldosterone system. Promising preclinical disease models and small clinical trials in non-DKD resulted in the initiation of phase 3 trials investigating the effects of long-term treatment with ERA in patients with immunoglobulin A (IgA) nephropathy and focal segmental glomeruloscelerosis (FSGS). The mechanisms by which ERA protects the kidneys have been extensively studied with evidence for the protection of tubule cells, podocytes, mesangial cells, the endothelial glycocalyx, and a reduction in glomerular perfusion pressure. The occurrence of fluid retention during ERA treatment, particularly in susceptible populations, necessitates strategies to support safe and effective treatment. SUMMARY: Treatment with ERA induces long-term kidney protection in DKD. Phase 3 trials are underway to investigate ERA effects in patients with IgA nephropathy and FSGS.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Insuficiência Renal Crônica , Atrasentana , Nefropatias Diabéticas/tratamento farmacológico , Antagonistas dos Receptores de Endotelina/uso terapêutico , Humanos , Insuficiência Renal Crônica/tratamento farmacológico , Sistema Renina-Angiotensina
7.
Clin Sci (Lond) ; 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34918049

RESUMO

Hypertension is a major risk factor for cardiovascular disease.  In a significant minority of people, it develops when salt intake is increased (salt-sensitivity).  It is not clear whether this represents impaired vascular function or disruption to the relationship between blood pressure (BP) and renal salt-handling (pressure natriuresis, PN).  Endothelin-1 (ET-1) regulates BP via ETA and ETB receptor subtypes.  Blockade of ETA receptors reduces BP, but promotes sodium retention by an unknown mechanism.  ETB blockade increases both BP and sodium retention.  We hypothesised that ETA blockade promotes sodium and water retention by suppressing PN.  We also investigated whether suppression of PN might reflect off-target ETB blockade.  Acute PN was induced by sequential arterial ligation in male Sprague Dawley rats.  Intravenous atrasentan (ETA antagonist, 5mg/kg) halved the normal increase in medullary perfusion and reduced sodium and water excretion by >60%.  This was not due to off-target ETB blockade because intravenous A-192621 (ETB antagonist, 10mg/kg) increased natriuresis by 50% without modifying medullary perfusion.  In a separate experiment in salt-loaded rats monitored by radiotelemetry, oral atrasentan reduced systolic and diastolic BP by ~10mmHg, but additional oral A-192621 reversed these effects.  Endogenous ETA stimulation has natriuretic effects mediated by renal vascular dilation while endogenous ETB stimulation in the kidney has antinatriuretic effects via renal tubular mechanisms.  Pharmacological manipulation of vascular function with ET antagonists modifies the BP set-point, but even highly selective ETA antagonists attenuate PN, which may be associated with salt and water retention.

8.
Kidney Int ; 98(2): 323-342, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32471642

RESUMO

Chronic kidney disease (CKD) is common, with hypertension and diabetes mellitus acting as major risk factors for its development. Cardiovascular disease is the leading cause of death worldwide and the most frequent end point of CKD. There is an urgent need for more precise methods to identify patients at risk of CKD and cardiovascular disease. Alterations in microvascular structure and function contribute to the development of hypertension, diabetes, CKD, and their associated cardiovascular disease. Homology between the eye and the kidney suggests that noninvasive imaging of the retinal vessels can detect these microvascular alterations to improve targeting of at-risk patients. Retinal vessel-derived metrics predict incident hypertension, diabetes, CKD, and cardiovascular disease and add to the current renal and cardiovascular risk stratification tools. The advent of optical coherence tomography (OCT) has transformed retinal imaging by capturing the chorioretinal microcirculation and its dependent tissue with near-histological resolution. In hypertension, diabetes, and CKD, OCT has revealed vessel remodeling and chorioretinal thinning. Clinical and preclinical OCT has linked retinal microvascular pathology to circulating and histological markers of injury in the kidney. The advent of OCT angiography allows contrast-free visualization of intraretinal capillary networks to potentially detect early incipient microvascular disease. Combining OCT's deep imaging with the analytical power of deep learning represents the next frontier in defining what the eye can reveal about the kidney and broader cardiovascular health.


Assuntos
Doenças Cardiovasculares , Insuficiência Renal Crônica , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Humanos , Rim/diagnóstico por imagem , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , Vasos Retinianos , Tomografia de Coerência Óptica
9.
Kidney Int ; 98(5): 1193-1209, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32569653

RESUMO

The endothelin system may be an important player in hypertensive end-organ injury as endothelin-1 increases blood pressure and is pro-inflammatory. The immune system is emerging as an important regulator of blood pressure and we have shown that the early hypertensive response to angiotensin-II infusion was amplified in mice deficient of myeloid endothelin-B (ETB) receptors (LysM-CreEdnrblox/lox). Hypothesizing that these mice would display enhanced organ injury, we gave angiotensin-II to LysM-CreEdnrblox/lox and littermate controls (Ednrblox/lox) for six weeks. Unexpectedly, LysM-CreEdnrblox/lox mice were significantly protected from organ injury, with less proteinuria, glomerulosclerosis and inflammation of the kidney compared to controls. In the eye, LysM-CreEdnrblox/lox mice had fewer retinal hemorrhages, less microglial activation and less vessel rarefaction. Cardiac remodeling and dysfunction were similar in both groups at week six but LysM-CreEdnrblox/lox mice had better endothelial function. Although blood pressure was initially higher in LysM-CreEdnrblox/lox mice, this was not sustained. A natriuretic switch at about two weeks, due to enhanced ETB signaling in the kidney, induced a hypertensive reversal. By week six, blood pressure was lower in LysM-CreEdnrblox/lox mice than in controls. At six weeks, macrophages from LysM-CreEdnrblox/lox mice were more anti-inflammatory and had greater phagocytic ability compared to the macrophages of Ednrblox/lox mice. Thus, myeloid cell ETB receptor signaling drives this injury both through amplifying hypertension and by inflammatory polarization of macrophages.


Assuntos
Angiotensina II , Hipertensão , Animais , Pressão Sanguínea , Endotelinas , Hipertensão/induzido quimicamente , Hipertensão/genética , Rim , Camundongos , Receptor de Endotelina B/genética
10.
Eur Heart J ; 40(9): 768-784, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30657897

RESUMO

AIMS: Hypertension is common. Recent data suggest that macrophages (Mφ) contribute to, and protect from, hypertension. Endothelin-1 (ET-1) is the most potent endogenous vasoconstrictor with additional pro-inflammatory properties. We investigated the role of the ET system in experimental and clinical hypertension by modifying Mφ number and phenotype. METHODS AND RESULTS: In vitro, Mφ ET receptor function was explored using pharmacological, gene silencing, and knockout approaches. Using the CD11b-DTR mouse and novel mice with myeloid cell-specific endothelin-B (ETB) receptor deficiency (LysMETB-/-), we explored the effects of modifying Mφ number and phenotype on the hypertensive effects of ET-1, angiotensin II (ANG II), a model that is ET-1 dependent, and salt. In patients with small vessel vasculitis, the impacts of Mφ depleting and non-depleting therapies on blood pressure (BP) and endothelial function were examined. Mouse and human Mφ expressed both endothelin-A and ETB receptors and displayed chemokinesis to ET-1. However, stimulation of Mφ with exogenous ET-1 did not polarize Mφ phenotype. Interestingly, both mouse and human Mφ cleared ET-1 through ETB receptor mediated, and dynamin-dependent, endocytosis. Mφ depletion resulted in an augmented chronic hypertensive response to both ET-1 and salt. LysMETB-/- mice displayed an exaggerated hypertensive response to both ET-1 and ANG II. Finally, in patients who received Mφ depleting immunotherapy BP was higher and endothelial function worse than in those receiving non-depleting therapies. CONCLUSION: Mφ and ET-1 may play an important role in BP control and potentially have a critical role as a therapeutic target in hypertension.


Assuntos
Angiotensina II/fisiologia , Endotelina-1/fisiologia , Hipertensão/patologia , Hipertensão/fisiopatologia , Macrófagos/fisiologia , Receptor de Endotelina B/fisiologia , Animais , Modelos Animais de Doenças , Endocitose/fisiologia , Humanos , Hipertensão/etiologia , Camundongos , Receptor de Endotelina A
11.
J Physiol ; 597(3): 767-780, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30537108

RESUMO

KEY POINTS: Type 1 diabetes mellitus increases cardiovascular risk; hypertension amplifies this risk, while pressure natriuresis regulates long-term blood pressure. We induced type 1 diabetes in rats by streptozotocin injection and demonstrated a substantial impairment of pressure natriuresis: acute increases in blood pressure did not increase renal medullary blood flow, tubular sodium reabsorption was not downregulated, and proximal tubule sodium reabsorption, measured by lithium clearance, was unaffected. Insulin reduced blood glucose in diabetic rats, and rescued the pressure natriuresis response without influencing lithium clearance, but did not restore medullary blood flow. Radiotelemetry showed that diastolic blood pressure was increased in diabetic rats, and its diurnal variation was reduced. Increases in medullary blood flow and decreases in distal tubule sodium reabsorption that offset acute rises in BP are impaired in early type 1 diabetes, and this impairment could be a target for preventing hypertension in type 1 diabetes. ABSTRACT: Type 1 diabetes mellitus (T1DM) substantially increases cardiovascular risk, and hypertension amplifies this risk. Blood pressure (BP) and body sodium homeostasis are linked. T1DM patients have increased total exchangeable sodium, correlating directly with BP. Pressure natriuresis is an important physiological regulator of BP. We hypothesised that pressure natriuresis would be impaired, and BP increased, in the early phase of T1DM. Male Sprague-Dawley rats were injected with streptozotocin (30-45 mg/kg) or citrate vehicle. After 3 weeks, pressure natriuresis was induced by serial arterial ligation. In non-diabetic controls, this increased fractional excretion of sodium from ∼1% to ∼25% of the filtered load (P < 0.01); in T1DM rats, the response was significantly blunted, peaking at only ∼3% (P < 0.01). Mechanistically, normal lithium clearance suggested that distal tubule sodium reabsorption was not downregulated with increased BP in T1DM rats. The pressure dependence of renal medullary perfusion, considered a key factor in the integrated response, was abolished. Insulin therapy rescued the natriuretic response in diabetic rats, restoring normal downregulation of tubular sodium reabsorption when BP was increased. However, the pressure dependence of medullary perfusion was not restored, suggesting persistent vascular dysfunction despite glycaemic control. Radiotelemetry showed that T1DM did not affect systolic BP, but mean diastolic BP was ∼5 mmHg higher than in non-diabetic controls (P < 0.01), and normal diurnal variation was reduced. In conclusion, functional impairment of renal sodium and BP homeostasis is an early manifestation of T1DM, preceding hypertension and nephropathy. Early intervention to restore pressure natriuresis in T1DM may complement reductions in cardiovascular risk achieved with glycaemic control.


Assuntos
Pressão Sanguínea/fisiologia , Diabetes Mellitus Experimental/fisiopatologia , Diabetes Mellitus Tipo 1/fisiopatologia , Natriurese/fisiologia , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Regulação para Baixo/fisiologia , Hemodinâmica/fisiologia , Hipertensão/fisiopatologia , Rim/metabolismo , Rim/fisiopatologia , Lítio/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Circulação Renal/fisiologia , Sódio/metabolismo
12.
Br J Clin Pharmacol ; 85(9): 1907-1924, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31206748

RESUMO

Weighing up sources of evidence is a key skill for clinical decision-makers. Randomised controlled trials (RCTs) and observational studies each have advantages and disadvantages, and in both cases perceived weaknesses can be improved through modifications of design and analysis. In the field of pharmacoepidemiology, RCTs are the best way to determine whether an intervention modifies an outcome being studied, largely because randomisation reduces bias and confounding. Observational studies are useful to investigate whether benefits/harms of a treatment are seen in day-to-day clinical practice in a wider group of patients. Although observational studies, even in a small cohort, can provide very useful clinical evidence, they may also be misleading (as shown by subsequent RCTs), in part because of allocation bias. There is an unmet need for clinicians to become well versed in appraising the study design and statistical analysis of observational pharmacoepidemiology (OP) studies, rather like the medical training already offered for RCT evaluation. This is because OP studies are likely to become more common with the computerisation of healthcare records and increasingly contribute to the evidence base available for clinical decision-making. However, when the results of an RCT conflict with the results of an OP study, the findings of the RCT should be preferred, especially if its findings have been repeated elsewhere. Conversely, OP studies that align with the findings of RCTs can provide rich and useful information to complement that generated by RCTs.


Assuntos
Tomada de Decisão Clínica/métodos , Farmacoepidemiologia/métodos , Interpretação Estatística de Dados , Humanos , Estudos Observacionais como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa
13.
Pharmacoepidemiol Drug Saf ; 28(10): 1369-1376, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31385428

RESUMO

PURPOSE: To validate an algorithm for acute exacerbations of chronic obstructive pulmonary disease (AECOPD) episodes derived in an electronic health record (EHR) database, against AECOPD episodes collected in a randomized clinical trial using an electronic case report form (eCRF). METHODS: We analyzed two data sources from the Salford Lung Study in COPD: trial eCRF and the Salford Integrated Record, a linked primary-secondary routine care EHR database of all patients in Salford. For trial participants, AECOPD episodes reported in eCRF were compared with algorithmically derived moderate/severe AECOPD episodes identified in EHR. Episode characteristics (frequency, duration), sensitivity, and positive predictive value (PPV) were calculated. A match between eCRF and EHR episodes was defined as at least 1-day overlap. RESULTS: In the primary effectiveness analysis population (n = 2269), 3791 EHR episodes (mean [SD] length: 15.1 [3.59] days; range: 14-54) and 4403 moderate/severe AECOPD eCRF episodes (mean length: 13.8 [16.20] days; range: 1-372) were identified. eCRF episodes exceeding 28 days were usually broken up into shorter episodes in the EHR. Sensitivity was 63.6% and PPV 71.1%, where concordance was defined as at least 1-day overlap. CONCLUSIONS: The EHR algorithm performance was acceptable, indicating that EHR-derived AECOPD episodes may provide an efficient, valid method of data collection. Comparing EHR-derived AECOPD episodes with those collected by eCRF resulted in slightly fewer episodes, and eCRF episodes of extreme lengths were poorly captured in EHR. Analysis of routinely collected EHR data may be reasonable when relative, rather than absolute, rates of AECOPD are relevant for stakeholders' decision making.


Assuntos
Registros Eletrônicos de Saúde/estatística & dados numéricos , Farmacoepidemiologia/métodos , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Exacerbação dos Sintomas , Idoso , Algoritmos , Ensaios Clínicos Fase III como Assunto/estatística & dados numéricos , Coleta de Dados/métodos , Bases de Dados Factuais/estatística & dados numéricos , Inglaterra/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Admissão do Paciente/estatística & dados numéricos , Farmacoepidemiologia/estatística & dados numéricos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/terapia , Sensibilidade e Especificidade , Índice de Gravidade de Doença
14.
Pharmacol Rev ; 68(2): 357-418, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26956245

RESUMO

The endothelins comprise three structurally similar 21-amino acid peptides. Endothelin-1 and -2 activate two G-protein coupled receptors, ETA and ETB, with equal affinity, whereas endothelin-3 has a lower affinity for the ETA subtype. Genes encoding the peptides are present only among vertebrates. The ligand-receptor signaling pathway is a vertebrate innovation and may reflect the evolution of endothelin-1 as the most potent vasoconstrictor in the human cardiovascular system with remarkably long lasting action. Highly selective peptide ETA and ETB antagonists and ETB agonists together with radiolabeled analogs have accurately delineated endothelin pharmacology in humans and animal models, although surprisingly no ETA agonist has been discovered. ET antagonists (bosentan, ambrisentan) have revolutionized the treatment of pulmonary arterial hypertension, with the next generation of antagonists exhibiting improved efficacy (macitentan). Clinical trials continue to explore new applications, particularly in renal failure and for reducing proteinuria in diabetic nephropathy. Translational studies suggest a potential benefit of ETB agonists in chemotherapy and neuroprotection. However, demonstrating clinical efficacy of combined inhibitors of the endothelin converting enzyme and neutral endopeptidase has proved elusive. Over 28 genetic modifications have been made to the ET system in mice through global or cell-specific knockouts, knock ins, or alterations in gene expression of endothelin ligands or their target receptors. These studies have identified key roles for the endothelin isoforms and new therapeutic targets in development, fluid-electrolyte homeostasis, and cardiovascular and neuronal function. For the future, novel pharmacological strategies are emerging via small molecule epigenetic modulators, biologicals such as ETB monoclonal antibodies and the potential of signaling pathway biased agonists and antagonists.


Assuntos
Endotelinas , Animais , Antagonistas dos Receptores de Endotelina/classificação , Antagonistas dos Receptores de Endotelina/farmacologia , Endotelinas/metabolismo , Humanos , Receptores de Endotelina/agonistas , Receptores de Endotelina/química , Receptores de Endotelina/metabolismo
15.
Diabetologia ; 60(8): 1400-1408, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28528401

RESUMO

AIMS/HYPOTHESIS: We investigated whether biochemical cardiovascular risk factors and/or markers of subclinical cardiovascular disease were associated with the development of reduced renal function in people with type 2 diabetes. METHODS: A cohort of 1066 Scottish men and women aged 60-74 years with type 2 diabetes from the Edinburgh Type 2 Diabetes Study were followed up for a median of 6.7 years. New-onset reduced renal function was defined as two eGFRs <60 ml-1 min-1 (1.73 m)-2 at least 3 months apart with a > 25% decline from baseline eGFR. Ankle brachial pressure index (ABI), N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity troponin T (hsTnT) were measured at baseline. Pulse wave velocity (PWV) and carotid intima media thickness were measured 1 year into follow-up. Data were analysed using Cox proportional hazards models. RESULTS: A total of 119 participants developed reduced renal function during follow-up. ABI, PWV, NT-proBNP and hsTnT were all associated with onset of decline in renal function following adjustment for age and sex. These associations were attenuated after adjustment for additional diabetes renal disease risk factors (systolic BP, baseline eGFR, albumin:creatinine ratio and smoking pack-years), with the exception of hsTnT which remained independently associated (HR 1.51 [95% CI 1.22, 1.87]). Inclusion of hsTnT in a predictive model improved the continuous net reclassification index by 0.165 (0.008, 0.286). CONCLUSIONS/INTERPRETATION: Our findings demonstrate an association between hsTnT, a marker of subclinical cardiac ischaemia, and subsequent renal function decline. Further research is required to establish the predictive value of hsTnT and response to intervention.


Assuntos
Biomarcadores/metabolismo , Doenças Cardiovasculares/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Idoso , Doenças Cardiovasculares/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Taxa de Filtração Glomerular/fisiologia , Humanos , Rim/metabolismo , Rim/patologia , Rim/fisiologia , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/metabolismo , Fragmentos de Peptídeos/metabolismo , Modelos de Riscos Proporcionais , Análise de Onda de Pulso , Fatores de Risco , Troponina T/metabolismo
16.
PLoS Med ; 14(2): e1002248, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28245243

RESUMO

BACKGROUND: Chronic liver scarring from any cause leads to cirrhosis, portal hypertension, and a progressive decline in renal blood flow and renal function. Extreme renal vasoconstriction characterizes hepatorenal syndrome, a functional and potentially reversible form of acute kidney injury in patients with advanced cirrhosis, but current therapy with systemic vasoconstrictors is ineffective in a substantial proportion of patients and is limited by ischemic adverse events. Serelaxin (recombinant human relaxin-2) is a peptide molecule with anti-fibrotic and vasoprotective properties that binds to relaxin family peptide receptor-1 (RXFP1) and has been shown to increase renal perfusion in healthy human volunteers. We hypothesized that serelaxin could ameliorate renal vasoconstriction and renal dysfunction in patients with cirrhosis and portal hypertension. METHODS AND FINDINGS: To establish preclinical proof of concept, we developed two independent rat models of cirrhosis that were characterized by progressive reduction in renal blood flow and glomerular filtration rate and showed evidence of renal endothelial dysfunction. We then set out to further explore and validate our hypothesis in a phase 2 randomized open-label parallel-group study in male and female patients with alcohol-related cirrhosis and portal hypertension. Forty patients were randomized 1:1 to treatment with serelaxin intravenous (i.v.) infusion (for 60 min at 80 µg/kg/d and then 60 min at 30 µg/kg/d) or terlipressin (single 2-mg i.v. bolus), and the regional hemodynamic effects were quantified by phase contrast magnetic resonance angiography at baseline and after 120 min. The primary endpoint was the change from baseline in total renal artery blood flow. Therapeutic targeting of renal vasoconstriction with serelaxin in the rat models increased kidney perfusion, oxygenation, and function through reduction in renal vascular resistance, reversal of endothelial dysfunction, and increased activation of the AKT/eNOS/NO signaling pathway in the kidney. In the randomized clinical study, infusion of serelaxin for 120 min increased total renal arterial blood flow by 65% (95% CI 40%, 95%; p < 0.001) from baseline. Administration of serelaxin was safe and well tolerated, with no detrimental effect on systemic blood pressure or hepatic perfusion. The clinical study's main limitations were the relatively small sample size and stable, well-compensated population. CONCLUSIONS: Our mechanistic findings in rat models and exploratory study in human cirrhosis suggest the therapeutic potential of selective renal vasodilation using serelaxin as a new treatment for renal dysfunction in cirrhosis, although further validation in patients with more advanced cirrhosis and renal dysfunction is required. TRIAL REGISTRATION: ClinicalTrials.gov NCT01640964.


Assuntos
Nefropatias/tratamento farmacológico , Rim/efeitos dos fármacos , Cirrose Hepática/tratamento farmacológico , Relaxina/farmacologia , Relaxina/uso terapêutico , Adolescente , Adulto , Idoso , Animais , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Rim/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Fluxo Sanguíneo Regional/efeitos dos fármacos , Escócia , Adulto Jovem
17.
Am Heart J ; 191: 37-46, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28888268

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is associated with increased left ventricular (LV) mass and arterial stiffness. In a previous trial, spironolactone improved these end points compared with placebo in subjects with early-stage CKD, but it is not known whether these effects were specific to the drug or secondary to blood pressure lowering. AIM: The aim was to investigate the hypothesis that spironolactone is superior to chlorthalidone in the reduction of LV mass while exerting similar effects on blood pressure. DESIGN: This is a multicenter, prospective, randomized, open-label, blinded end point clinical trial initially designed to compare the effects of 40weeks of treatment with spironolactone 25mg once daily to chlorthalidone 25mg once daily on the co-primary end points of change in pulse wave velocity and change in LV mass in 350 patients with stages 2 and 3 CKD on established treatment with an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Because of slow recruitment rates, it became apparent that it would not be possible to recruit this sample size within the funded time period. The study design was therefore changed to one with a single primary end point of LV mass requiring 150 patients. Recruitment was completed on 31 December 2016, at which time 154 patients had been recruited. Investigations included cardiac magnetic resonance imaging, applanation tonometry, 24-hour ambulatory blood pressure monitoring, and laboratory tests. Subjects are assessed before and after 40weeks of randomly allocated drug therapy and at 46weeks after discontinuation of the study drug.


Assuntos
Clortalidona/administração & dosagem , Ventrículos do Coração/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/etiologia , Falência Renal Crônica/complicações , Espironolactona/administração & dosagem , Adulto , Idoso , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Seguimentos , Ventrículos do Coração/fisiopatologia , Humanos , Hipertrofia Ventricular Esquerda/mortalidade , Hipertrofia Ventricular Esquerda/fisiopatologia , Falência Renal Crônica/mortalidade , Falência Renal Crônica/fisiopatologia , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Antagonistas de Receptores de Mineralocorticoides/administração & dosagem , Estudos Prospectivos , Análise de Onda de Pulso , Método Simples-Cego , Inibidores de Simportadores de Cloreto de Sódio/administração & dosagem , Taxa de Sobrevida/tendências , Fatores de Tempo , Resultado do Tratamento , Estados Unidos/epidemiologia , Rigidez Vascular
18.
Br J Clin Pharmacol ; 83(10): 2249-2258, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28449302

RESUMO

AIMS: Newly graduated doctors write a large proportion of prescriptions in UK hospitals but recent studies have shown that they frequently make prescribing errors. The prescribing safety assessment (PSA) has been developed as an assessment of competence in relation to prescribing and supervising the use of medicines. This report describes the delivery of the PSA to all UK final-year medical students in 2016 (PSA2016). METHODS: The PSA is a 2-hour online assessment comprising eight sections which cover various aspects of prescribing defined within the outcomes of undergraduate education identified by the UK General Medical Council. Students sat one of four PSA 'papers', which had been standard-set using a modified Angoff process. RESULTS: A total of 7343 final-year medical students in all 31 UK medical schools sat the PSA. The overall pass rate was 95% with the pass rates for the individual papers ranging from 93 to 97%. The PSA was re-sat by 261 students who had failed and 80% of those candidates passed. The internal consistency (Cronbach's alpha) of the four papers ranged from 0.74 to 0.77 (standard error of measurement 4.13-4.24%). There was a statistically significant variation in performance between medical school cohorts (F = 32.6, P < 0.001) and a strongly positive correlation in performance for individual schools between PSA2015 and PSA2016 (r = 0.79, 95% CI 0.61-0.90; P < 0.01). CONCLUSIONS: PSA2016 demonstrated the feasibility of delivering a standardized national prescribing assessment online. The vast majority of UK final-year medical students were able to meet a prespecified standard of prescribing competence.


Assuntos
Prescrições de Medicamentos , Educação de Graduação em Medicina/organização & administração , Avaliação Educacional/métodos , Erros de Medicação/prevenção & controle , Faculdades de Medicina/organização & administração , Desempenho Acadêmico/estatística & dados numéricos , Competência Clínica , Educação de Graduação em Medicina/estatística & dados numéricos , Estudos de Viabilidade , Humanos , Estudantes de Medicina/estatística & dados numéricos , Reino Unido
19.
Br J Clin Pharmacol ; 83(11): 2339-2342, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28681444

RESUMO

This is a joint statement from individual pharmacology and pharmaceutical professionals acting in their own capacity, including members of the Alliance for Clinical Research Excellence and Safety (ACRES) and the International Society of Pharmacovigilance (ISoP). By building on the extensive pharmacological and regulatory investigations that already take place, we are calling for a fuller and more robust systems-based approach to the independent investigation of clinical research when serious incidents of harm occur, starting with first-in-human clinical trials. To complement existing activities and regulations, we propose an additional approach blending evidence derived from both pharmacological and organizational science, which addresses human factors and transparency, to enhance organizational learning and continuous improvement. As happens with investigations in other sectors of society, such as the chemical and aviation sector, this systems approach should be seen as an additional way to understand how problems occur and how they might be prevented in the future. We believe that repetition of potentially preventable and adverse outcomes during clinical research, by failing to identify and act upon all systematic vulnerabilities, is a situation that needs urgent change. As we will discuss further on, approaches based on applying systems theory and human factors are much more likely to improve objectivity and transparency, leading to better system design.


Assuntos
Atenção à Saúde/organização & administração , Experimentação Humana , Farmacovigilância , Melhoria de Qualidade/organização & administração , Teoria de Sistemas , Anticorpos Monoclonais Humanizados/efeitos adversos , Ensaios Clínicos Fase I como Assunto , Óxidos N-Cíclicos/efeitos adversos , Atenção à Saúde/legislação & jurisprudência , Humanos , Piridinas/efeitos adversos
20.
J Am Soc Nephrol ; 27(11): 3345-3355, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27020854

RESUMO

Extracellular vesicles (ECVs) facilitate intercellular communication along the nephron, with the potential to change the function of the recipient cell. However, it is not known whether this is a regulated process analogous to other signaling systems. We investigated the potential hormonal regulation of ECV transfer and report that desmopressin, a vasopressin analogue, stimulated the uptake of fluorescently loaded ECVs into a kidney collecting duct cell line (mCCDC11) and into primary cells. Exposure of mCCDC11 cells to ECVs isolated from cells overexpressing microRNA-503 led to downregulated expression of microRNA-503 target genes, but only in the presence of desmopressin. Mechanistically, ECV entry into mCCDC11 cells required cAMP production, was reduced by inhibiting dynamin, and was selective for ECVs from kidney tubular cells. In vivo, we measured the urinary excretion and tissue uptake of fluorescently loaded ECVs delivered systemically to mice before and after administration of the vasopressin V2 receptor antagonist tolvaptan. In control-treated mice, we recovered 2.5% of administered ECVs in the urine; tolvaptan increased recovery five-fold and reduced ECV deposition in kidney tissue. Furthermore, in a patient with central diabetes insipidus, desmopressin reduced the excretion of ECVs derived from glomerular and proximal tubular cells. These data are consistent with vasopressin-regulated uptake of ECVs in vivo We conclude that ECV uptake is a specific and regulated process. Physiologically, ECVs are a new mechanism of intercellular communication; therapeutically, ECVs may be a vehicle by which RNA therapy could be targeted to specific cells for the treatment of kidney disease.


Assuntos
Vesículas Extracelulares/fisiologia , Túbulos Renais Coletores/citologia , Vasopressinas/fisiologia , Adolescente , Animais , Desamino Arginina Vasopressina/farmacologia , Vesículas Extracelulares/efeitos dos fármacos , Humanos , Túbulos Renais Coletores/ultraestrutura , Masculino , Camundongos , Ratos
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