RÉSUMÉ
BACKGROUND: Increased arterial stiffness and pulse wave velocity (PWV) of the aorta and large arteries impose adverse hemodynamic effects on the heart and other organs. Antihypertensive treatment reduces PWV, but it is unknown whether this results from an unloading of stiffer elements in the arterial wall or is due to an alternate functional or structural change that might differ according to class of antihypertensive drug. METHODS: We performed a systematic review and meta-analysis of the effects of different antihypertensive drug classes and duration of treatment on PWV with and without adjustment for change in mean arterial blood pressure (BP; study 1) and compared this to the change in PWV after an acute change in transmural pressure, simulating an acute change in BP (study 2). RESULTS: A total of 83 studies involving 6200 subjects were identified. For all drug classes combined, the reduction of PWV was 0.65 (95% CI, 0.46-0.83) m/s per 10 mmâ Hg reduction in mean arterial BP, a change similar to that induced by an acute change in transmural pressure in a group of hypertensive subjects. When adjusted for change in mean arterial BP, the reduction in PWV after treatment with beta-blockers or diuretics was less than that after treatment with angiotensin-converting enzyme inhibitors/angiotensin receptor antagonists or calcium channel antagonists. CONCLUSIONS: Reduction in PWV after antihypertensive treatment is largely explained by the reduction in BP, but there are some BP-independent effects. These might increase over time and contribute to better outcomes over the long term, but this remains to be demonstrated in long-term clinical trials.
Sujet(s)
Antihypertenseurs , Pression sanguine , Hypertension artérielle , Analyse de l'onde de pouls , Rigidité vasculaire , Humains , Analyse de l'onde de pouls/méthodes , Hypertension artérielle/physiopathologie , Hypertension artérielle/traitement médicamenteux , Antihypertenseurs/usage thérapeutique , Rigidité vasculaire/physiologie , Rigidité vasculaire/effets des médicaments et des substances chimiques , Pression sanguine/physiologie , Pression sanguine/effets des médicaments et des substances chimiquesRÉSUMÉ
OBJECTIVE: Errors in blood pressure (BP) measurement account for a large proportion of misclassified hypertension diagnoses. Ambulatory blood pressure monitoring (ABPM) is often considered to be the gold standard for measurement of BP, but uncertainty remains regarding the degree of measurement error. The aim of this study was to determine reproducibility of sequential ABPM in a population of normotensive and well controlled hypertensive individuals. METHODS: Individual participant data from three randomized controlled trials, which had recorded ABPM and carotid-femoral pulse wave velocity (PWV) at least twice were combined ( n â=â501). We calculated within-individual variability of daytime and night-time BP and compared the variability between normotensive ( n â=â324) and hypertensive ( n â=â177) individuals. As a secondary analysis, variability of PWV measurements was also calculated, and multivariable linear regression was used to assess characteristics associated with blood pressure variability (BPV). RESULTS: Within-individual coefficient of variation (CoV) for systolic BP was 5.4% (day) and 7.0% (night). Equivalent values for diastolic BP were 6.1% and 8.4%, respectively. No statistically significant difference in CoV was demonstrated between measurements for normotensive and hypertensive individuals. Within-individual CoV for PWV exceeded that of BP measurements (10.7%). BPV was associated with mean pressures, and BMI for night-time measurements. PWV was not independently associated with BPV. CONCLUSION: The variability of single ABPM measurements will still yield considerable uncertainty regarding true average pressures, potentially resulting in misclassification of hypertensive status and incorrect treatment regimes. Repeated ABPM may be necessary to refine antihypertensive therapy.
Sujet(s)
Surveillance ambulatoire de la pression artérielle , Hypertension artérielle , Humains , Surveillance ambulatoire de la pression artérielle/méthodes , Pression sanguine , Analyse de l'onde de pouls , Reproductibilité des résultatsRÉSUMÉ
There is a strong and ever-growing body of evidence regarding the use of pharmacogenomics to inform cardiovascular pharmacology. However, there is no common position taken by international cardiovascular societies to unite diverse availability, interpretation, and application of such data, nor is there recognition of the challenges of variation in clinical practice between countries within Europe. Aside from the considerable barriers to implementing pharmacogenomic testing and the complexities of clinically actioning results, there are differences in the availability of resources and expertise internationally within Europe. Diverse legal and ethical approaches to genomic testing and clinical therapeutic application also require serious thought. As direct-to-consumer genomic testing becomes more common, it can be anticipated that data may be brought in by patients themselves, which will require critical assessment by the clinical cardiovascular prescriber. In a modern, pluralistic and multi-ethnic Europe, self-identified race/ethnicity may not be concordant with genetically detected ancestry and thus may not accurately convey polymorphism prevalence. Given the broad relevance of pharmacogenomics to areas, such as thrombosis and coagulation, interventional cardiology, heart failure, arrhythmias, clinical trials, and policy/regulatory activity within cardiovascular medicine, as well as to genomic and pharmacology subspecialists, this position statement attempts to address these issues at a wide-ranging level.
Sujet(s)
Cardiologie , Système cardiovasculaire , Défaillance cardiaque , Europe , Humains , PharmacogénétiqueRÉSUMÉ
Pharmacogenomics promises to advance cardiovascular therapy, but there remain pragmatic barriers to implementation. These are particularly important to explore within Europe, as there are differences in the populations, availability of resources, and expertise, as well as in ethico-legal frameworks. Differences in healthcare delivery across Europe present a challenge, but also opportunities to collaborate on pharmacogenomics implementation. Clinical workforce upskilling is already in progress but will require substantial input. Digital infrastructure and clinical support tools are likely to prove crucial. It is important that widespread implementation serves to narrow rather than widen any existing gaps in health equality between populations. This viewpoint supplements the working group position paper on cardiovascular pharmacogenomics to address these important themes.
Sujet(s)
Cardiologie , Système cardiovasculaire , Europe , Humains , PharmacogénétiqueRÉSUMÉ
[Figure: see text].
Sujet(s)
Antihypertenseurs/usage thérapeutique , Hypertension artérielle , Gestion de la pharmacothérapie/statistiques et données numériques , Biais (épidémiologie) , Pression sanguine/effets des médicaments et des substances chimiques , Simulation numérique , Humains , Hypertension artérielle/diagnostic , Hypertension artérielle/traitement médicamenteux , Hypertension artérielle/physiopathologie , Gestion de la pharmacothérapie/normes , Méthode de Monte Carlo , Types de pratiques des médecins/normes , Types de pratiques des médecins/statistiques et données numériques , Amélioration de la qualité , Appréciation des risques/méthodes , TempsRÉSUMÉ
AIMS: Dietary nitrate from sources such as beetroot juice lowers blood pressure (BP) via the nitrate-nitrite-nitric oxide (NO) pathway. However, NO and nitrite are inactivated via reoxidation to nitrate, potentially limiting their activity. Cytochrome P450-3A4 inhibition with troleandomycin prevents nitrite re-oxidation to nitrate in rodent liver. Grapefruit juice contains the CYP3A4 inhibitor furanocoumarin. We therefore hypothesized that grapefruit juice would enhance BP-lowering with beetroot juice by maintaining circulating [nitrite]. METHODS: We performed a randomized, placebo-controlled, 7-hour crossover study in 11 healthy volunteers, attending on 3 occasions, receiving: a 70-mL shot of active beetroot juice (Beet-It) and either (i) 250 mL grapefruit juice (Active Beet+GFJ), or (ii) 250 mL water (Buxton, Active Beet+H2 O); or (iii) Placebo Beet+GFJ. RESULTS: The addition of grapefruit juice to active beetroot juice lowered systolic BP (SBP): Active Beet+GFJ vs Active Beet+H2 O (P = .02), and pulse pressure, PP (P = .0003). Peak mean differences in SBP and PP were seen at T = 5 hours: -3.3 mmHg (95% confidence interval [CI] -6.43 to -0.15) and at T = 2.5 hours: -4.2 mmHg (95% CI -0.3 to -8.2), respectively. Contrary to the hypothesis, plasma [nitrite] was lower with Active Beet+GFJ vs Active Beet+H2 O (P = .006), as was salivary nitrite production (P = .002) and saliva volume (-0.34 mL/min [95% CI -0.05 to -0.68]). The taste score of Beet+GFJ was 1.4/10 points higher than Beet+H2 O (P = .03). CONCLUSION: Grapefruit juice enhanced beetroot juice's effect on lowering SBP and PP despite decreasing plasma [nitrite]. Besides suggesting more complex mechanisms, there is potential for maximising the clinical benefit of dietary nitrate and targeting isolated systolic hypertension.
Sujet(s)
Beta vulgaris , Citrus paradisi , Pression sanguine , Études croisées , Compléments alimentaires , Jus de fruits et de légumes , NitratesRÉSUMÉ
The 2011 NICE hypertension guideline (CG127) undertook a systematic review of the diagnostic accuracy of different blood pressure (BP) assessment methods to confirm the diagnosis of hypertension. The guideline also undertook a cost-utility analysis exploring the cost-effectiveness of the monitoring methods. A new systematic review was undertaken as part of the 2019 NICE hypertension guideline update (NG136). BP monitoring methods compared included Ambulatory BP, Clinic BP and Home BP. Ambulatory BP was the reference standard. The economic model from the 2011 guideline was updated with this new accuracy data. Home BP was more sensitive and specific than Clinic BP. Specificity improved more than sensitivity since the 2011 review. A higher specificity translates into fewer people requiring unnecessary treatment. A key interest was to compare Home BP and Ambulatory BP, and whether any improvement in Home BP accuracy would change the model results. Ambulatory BP remained the most cost-effective option in all age and sex subgroups. In all subgroups, Ambulatory BP was associated with lower costs than Clinic BP and Home BP. In all except one subgroup (females aged 40), Ambulatory BP was dominant. However, Ambulatory BP remained the most cost-effective option in 40-year-old females as the incremental cost-effectiveness ratio for Home BP versus Ambulatory BP was above the NICE £20,000 threshold. The new systematic review showed that the accuracy of both Clinic BP and Home BP has increased. However, Ambulatory BP remains the most cost-effective option to confirm a diagnosis of hypertension in all subgroups evaluated.
Sujet(s)
Surveillance ambulatoire de la pression artérielle , Hypertension artérielle , Adulte , Pression sanguine , Mesure de la pression artérielle , Femelle , Humains , Hypertension artérielle/diagnostic , Modèles économiques , Soins de santé primairesRÉSUMÉ
AIMS: Plasma renin activity (PRA) is regarded as a marker of sodium and fluid homeostasis in patients with primary hypertension. Whether effects of diuretics on PRA differ according to class of diuretic, whether diuretics lead to a sustained increase in PRA, and whether changes in PRA relate to those in blood pressure (BP) is unknown. We performed a systematic review and meta-analysis of trials investigating the antihypertensive effects of diuretic therapy in which PRA and/or other biomarkers of fluid homeostasis were measured before and after treatment. METHODS: Three databases were searched: MEDLINE, EMBASE and The Cochrane Central Register of Controlled Trials. Titles were firstly screened by title and abstract for relevancy before full-text articles were assessed for eligibility according to a predefined inclusion/exclusion criteria. RESULTS: A total of 1684 articles were retrieved of which 61 met the prespecified inclusion/exclusion criteria. PRA was measured in 30/61 studies. Diuretics led to a sustained increase in PRA which was similar for different classes of diuretic (standardised mean difference [95% confidence interval] 0.481 [0.362, 0.601], 0.729 [0.181, 1.28], 0.541 [0.253, 0.830] and 0.548 [0.159, 0.937] for thiazide, loop, mineralocorticoid receptor antagonists/potassium-sparing and combination diuretics respectively, Q = 0.897, P = .826), and did not relate to the average decrease in blood pressure. CONCLUSION: In antihypertensive drug trials, diuretics lead to a sustained increase in average PRA, which is similar across different classes of diuretic and unrelated to the average reduction in blood pressure.
Sujet(s)
Hypertension artérielle , Rénine , Antihypertenseurs/pharmacologie , Antihypertenseurs/usage thérapeutique , Pression sanguine , Diurétiques/pharmacologie , Diurétiques/usage thérapeutique , Humains , Hypertension artérielle/traitement médicamenteux , Rénine/pharmacologieRÉSUMÉ
Antihypertensive drug treatment is cost-effective for adults at high risk of developing cardiovascular disease (CVD). However, the cost-effectiveness in people with stage 1 hypertension (140-159 mm Hg systolic blood pressure) at lower CVD risk remains unclear. The objective was to establish the 10-year CVD risk threshold where initiating antihypertensive drug treatment for primary prevention in adults, with stage 1 hypertension, becomes cost-effective. A lifetime horizon Markov model compared antihypertensive drug versus no treatment, using a UK National Health Service perspective. Analyses were conducted for groups ranging between 5% and 20% 10-year CVD risk. Health states included no CVD event, CVD and non-CVD death, and 6 nonfatal CVD morbidities. Interventions were compared using cost-per-quality-adjusted life-years. The base-case age was 60, with analyses repeated between ages 40 and 75. The model was run separately for men and women, and threshold CVD risk assessed against the minimum plausible risk for each group. Treatment was cost-effective at 10% CVD risk for both sexes (incremental cost-effectiveness ratio £10 017/quality-adjusted life-year [$14 542] men, £8635/QALY [$12 536] women) in the base-case. The result was robust in probabilistic and deterministic sensitivity analyses but was sensitive to treatment effects. Treatment was cost-effective for men regardless of age and women aged >60. Initiating treatment in stage 1 hypertension for people aged 60 is cost-effective regardless of 10-year CVD risk. For other age groups, it is also cost-effective to treat regardless of risk, except in younger women.
Sujet(s)
Antihypertenseurs/usage thérapeutique , Pression sanguine/effets des médicaments et des substances chimiques , Maladies cardiovasculaires/prévention et contrôle , Hypertension artérielle/traitement médicamenteux , Modèles théoriques , Adulte , Antihypertenseurs/économie , Antihypertenseurs/pharmacologie , Maladies cardiovasculaires/économie , Analyse coût-bénéfice , Femelle , Humains , Hypertension artérielle/économie , Mâle , Adulte d'âge moyen , Années de vie ajustées sur la qualitéRÉSUMÉ
OBJECTIVES: To assess the impact of variable drug response and measurement error on SBP control. METHODS: We simulated a treat-to-target strategy for populations with different pretreatment SBP, whereby medications were added sequentially until measured SBP (mSBP) less than 140âmmHg. Monte Carlo simulations determined variability of both drug response (drugeffâ±âσdrug; 10â±â5âmmHg base case) and measurement error (σmeas; 10âmmHg base case) of true SBP (tSBP). The primary outcome measure was the proportion of individuals who achieved target less than 140âmmHg. RESULTS: Decision-making based on mSBP resulted in 35.0% of individuals with initial tSBP 150âmmHg being either inappropriately given, or inappropriately denied a second drug. When the simulation was run for multiple drug titrations, measurement error limited tSBP control for all populations tested. A strategy of drug titration based on a second measurement for individuals at risk of incorrect decisions (mSBP 120-150âmmHg; σmeas 15âmmHg) reduced the proportion above target from 40.1 to 30.0% when initial tSBP 160âmmHg. When the measurement variability for the second reading was reduced below that usually seen in clinical practice (σmeas 5âmmHg), the proportion above target decreased further to 17.4%. CONCLUSION: In this simulation, measurement error had the greatest impact on the proportion of individuals achieving their SBP target. Efforts to reduce this error through repeated measures, alternative measurement techniques or changing thresholds, are promising strategies to reduce cardiovascular morbidity and mortality and should be investigated in clinical trials. Here we have shown that Monte Carlo simulations are a useful technique to investigate the influence of uncertainty for different hypertension management strategies.
Sujet(s)
Antihypertenseurs , Pression sanguine/effets des médicaments et des substances chimiques , Simulation numérique , Hypertension artérielle , Méthode de Monte Carlo , Antihypertenseurs/pharmacologie , Antihypertenseurs/usage thérapeutique , Humains , Hypertension artérielle/traitement médicamenteux , Hypertension artérielle/physiopathologie , IncertitudeRÉSUMÉ
BACKGROUND: Atrial arrhythmias are common in patients with atrial septal defects (ASD) but the effects of percutaneous closure on atrial arrhythmia prevalence is unclear. We investigated the effects of ASD device closure and the impact of age at time of closure on prevalent atrial arrythmia. METHODS: Meta-analysis of studies reporting atrial arrhythmia prevalence in adult patients before and after percutaneous closure was performed. Primary outcomes were prevalence of 'all atrial arrhythmia' and atrial fibrillation alone post closure. Sub-group analysis examined the effects of closure according to age in patients; <40 years, ≥40 and ≥ 60 years. 25 studies were included. RESULTS: Meta-analysis of all studies demonstrated no reduction in all atrial arrhythmia or atrial fibrillation prevalence post-closure (OR 0.855, 95% CI 0.672 to 1.087, P = .201 and OR 0.818, 95% CI 0.645 to 1.038, P = .099, respectively). A weak reduction in all atrial arrhythmia and atrial fibrillation was seen in patients ≥40 years (OR 0.77, 95% CI 0.616 to 0.979, P = .032 and OR 0.760, 95% CI 0.6 to 0.964, P = .024, respectively) but not ≥60 years (OR 0.822, 95% CI 0.593 to 1.141, P = .242 and OR 0.83, 95% CI 0.598 to 1.152, P = .266, respectively). No data were available in patients <40 years. This, and other limitations, prevents conclusive assessment of the effect of age on arrhythmia prevalence. CONCLUSIONS: Overall, percutaneous ASD closure is not associated with a reduction in atrial arrhythmia prevalence in this meta-analysis. A weak benefit is seen in patients ≥40 years of age, not present in patients ≥60 years.
Sujet(s)
Fibrillation auriculaire , Communications interauriculaires , Dispositif d'occlusion septale , Adulte , Fibrillation auriculaire/diagnostic , Fibrillation auriculaire/épidémiologie , Fibrillation auriculaire/chirurgie , Cathétérisme cardiaque , Communications interauriculaires/imagerie diagnostique , Communications interauriculaires/épidémiologie , Communications interauriculaires/chirurgie , Humains , Prévalence , Résultat thérapeutiqueSujet(s)
Pression sanguine/effets des médicaments et des substances chimiques , Gaz naturel , Nitrites/sang , Dioxyde d'azote , Pollution de l'air intérieur , Marqueurs biologiques/sang , Cuisine (activité) , Études croisées , Volontaires sains , Articles ménagers , Humains , Exposition par inhalation , Facteurs temps , Régulation positiveRÉSUMÉ
PURPOSE OF REVIEW: The coronavirus disease 2019 (COVID-19) pandemic has forced a redesign of healthcare services. Resource reallocation will have consequences on the routine management of chronic diseases, including cardiovascular disease (CVD). We consider how to mitigate potential adverse effects. RECENT FINDINGS: Combination therapy is well established in hypertension. Many guidelines recommend dual antihypertensive therapy as the initial treatment step as this results in faster blood pressure control, albeit with limited evidence of improved outcomes. Control of CVD risk factors through multiclass combination therapy (the polypill) was proposed many years ago. This approach has not been adopted by Western healthcare systems despite improving surrogate outcomes. Recently, the PolyIran trials have demonstrated improved CVD outcomes without increased adverse events, in both primary and secondary prevention. SUMMARY: The COVID-19 pandemic allows models of chronic healthcare to be rethought. Current practices are resource-intensive and there is a need to simplify titration and monitoring protocols in CVD. Moving toward the use of polypill combinations allied with telehealth consultations may be one solution.
Sujet(s)
Maladies cardiovasculaires , Infections à coronavirus , Coronavirus , Pandémies , Pneumopathie virale , Antihypertenseurs/administration et posologie , Betacoronavirus , COVID-19 , Maladies cardiovasculaires/complications , Maladies cardiovasculaires/traitement médicamenteux , Infections à coronavirus/épidémiologie , Prestations des soins de santé , Association médicamenteuse , Humains , Antiagrégants plaquettaires/administration et posologie , Pneumopathie virale/épidémiologie , SARS-CoV-2RÉSUMÉ
Dual antiplatelet therapy (DAPT) is integral to the management of coronary artery disease (CAD) but there remains uncertainty as to the optimal approach for balancing an individual's risk of atherothrombotic events versus their risk of bleeding complications. A myriad of clinical trials have investigated how factors such as antiplatelet selection or duration of treatment can affect outcomes in both stable CAD and acute coronary syndromes. To aid clinicians in the challenge of applying trial findings to the circumstances of individual patients, the American College of Cardiology/American Heart Association and European Society of Cardiology have released focused updates on prescribing DAPT in CAD. While the two guidelines agree on many issues, there are some differences in the recommendations. This article highlights those differences and provides comment on their aetiology.
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Mesure de la pression artérielle/normes , Hypertension artérielle/thérapie , Guides de bonnes pratiques cliniques comme sujet , Adulte , Antihypertenseurs/administration et posologie , Pression sanguine/effets des médicaments et des substances chimiques , Mesure de la pression artérielle/méthodes , Agences gouvernementales/normes , Mise en oeuvre des programmes de santé/méthodes , Mise en oeuvre des programmes de santé/normes , Humains , Hypertension artérielle/diagnostic , Comportement de réduction des risques , Royaume-UniRÉSUMÉ
The clinical doses of antithrombotics-antiplatelet and anticoagulant agents-need to balance efficacy and safety. It is not clear from the published literature how the doses currently used in clinical practice have been derived from preclinical and clinical data. There are few large randomised controlled trials (RCTs) that compare outcomes with different doses vs placebo. For newer antithrombotics, RCT doses appear to have been chosen to maximise the probability of demonstrating noninferiority when compared to established agents such as warfarin or clopidogrel. Data from RCTs show that aspirin is an effective antithrombotic at doses below 75 mg daily, and that direct oral anticoagulants reduce the risk of stroke in patients with coronary disease at doses 1/4 of those recommended in atrial fibrillation. Lower doses than those currently recommended are safer and still maintain substantial efficacy.
Sujet(s)
Anticoagulants/administration et posologie , Antiagrégants plaquettaires/administration et posologie , Anticoagulants/effets indésirables , Acide acétylsalicylique/administration et posologie , Acide acétylsalicylique/effets indésirables , Fibrillation auriculaire/complications , Fibrillation auriculaire/traitement médicamenteux , Clopidogrel/administration et posologie , Clopidogrel/effets indésirables , Maladie coronarienne/complications , Maladie coronarienne/traitement médicamenteux , Relation dose-effet des médicaments , Humains , Antiagrégants plaquettaires/effets indésirables , Essais contrôlés randomisés comme sujet , Accident vasculaire cérébral/étiologie , Accident vasculaire cérébral/prévention et contrôle , Warfarine/administration et posologie , Warfarine/effets indésirablesRÉSUMÉ
AIMS: Dietary inorganic nitrate (NO3- ) lowers peripheral blood pressure (BP) in healthy volunteers, but lacks such effect in individuals with, or at risk of, type 2 diabetes mellitus (T2DM). Whilst this is commonly assumed to be a consequence of chronic hyperglycaemia/hyperinsulinaemia, we hypothesized that acute physiological elevations in plasma [glucose]/[insulin] blunt the haemodynamic responses to NO3- , a pertinent question for carbohydrate-rich Western diets. METHODS: We conducted an acute, randomized, placebo-controlled, double-blind, crossover study on the haemodynamic and metabolic effects of potassium nitrate (8 or 24 mmol KNO3 ) vs. potassium chloride (KCl; placebo) administered 1 hour prior to an oral glucose tolerance test in 33 healthy volunteers. RESULTS: Compared to placebo, there were no significant differences in systolic or diastolic BP (P = 0.27 and P = 0.30 on ANOVA, respectively) with KNO3 , nor in pulse wave velocity or central systolic BP (P = 0.99 and P = 0.54 on ANOVA, respectively). Whilst there were significant elevations from baseline for plasma [glucose] and [C-peptide], no differences between interventions were observed. A significant increase in plasma [insulin] was observed with KNO3 vs. KCl (n = 33; P = 0.014 on ANOVA) with the effect driven by the high-dose cohort (24 mmol, n = 13; P < 0.001 on ANOVA; at T = 0.75 h mean difference 210.4 pmol/L (95% CI 28.5 to 392.3), P = 0.012). CONCLUSIONS: In healthy adults, acute physiological elevations of plasma [glucose] and [insulin] result in a lack of BP-lowering with dietary nitrate. The increase in plasma [insulin] without a corresponding change in [C-peptide] or [glucose] suggests that high-dose NO3- decreases insulin clearance. A likely mechanism is via NO-dependent inhibition of insulin-degrading enzyme.
Sujet(s)
Glycémie/métabolisme , Pression sanguine/effets des médicaments et des substances chimiques , Insuline/sang , Nitrates/pharmacologie , Composés du potassium/pharmacologie , Adulte , Études croisées , Méthode en double aveugle , Femelle , Glucose/administration et posologie , Glucose/métabolisme , Hyperglycémie provoquée , Humains , Mâle , Nitrates/administration et posologie , Monoxyde d'azote/métabolisme , Chlorure de potassium/administration et posologie , Chlorure de potassium/pharmacologie , Composés du potassium/administration et posologie , Analyse de l'onde de pouls , Jeune adulteRÉSUMÉ
PURPOSE: Gamma-hydroxybutyrate (GHB) withdrawal is a life-threatening condition that does not always respond to standard treatment with benzodiazepines. Baclofen has potential utility as a pharmacological adjunct and anecdotal reports suggest that it is being used by drug users to self-manage GHB withdrawal symptoms. Here, we investigate current patterns of use and the online availably of baclofen. METHODS: Data triangulation techniques were applied to published scientific literature and publicly accessible Internet resources (grey literature) to assess the use of baclofen in GHB withdrawal. An Internet snapshot survey was performed to identify the availability of baclofen for online purchase and the compliance of retailers with the UK regulations. Data were collected according to pre-defined criteria. RESULTS: A total of 37 cases of baclofen use in GHB withdrawal were identified in the scientific literature, as well as 51 relevant discussion threads across eight Internet forums in the grey literature. Baclofen was available to purchase from 38 online pharmacies, of which only one conformed to the UK regulations. CONCLUSIONS: There is limited published evidence on the use of baclofen in GHB withdrawal, but both scientific and grey literature suggests clinical utility. Online pharmacies are readily offering prescription-only-medication without prescription and due to inadequate regulation, pose a danger to the public.