Novel insights in the prevention of perinatal transmission of hepatitis B

Perinatal transmission of hepatitis B virus (HBV) infection is major contributor to the growing burden of chronic hepatitis B worldwide. Administration of HBV immunoglobulin and HBV vaccination as soon after pregnancy as possible are the mainstay of prevention of perinatal transmission of HBV infection. In women with high viral loads, antiviral prophylaxis also appears to be useful. Lamivudine, telbivudine and tenofovir have been shown to be both safe and effective in this setting but tenofovir is the first-line option due to its low potential for resistance and more favorable safety profile.

CONGRESS COVERAGE: Antihypertensive Therapy in Acute Ischemic Stroke: Lost in the Mist

The results of the China Antihypertensive Trial in Acute Ischemic Stroke (CATIS) study were presented last month at the 2013 American Heart Association Scientific Meeting and simultaneously published in the Journal of the American Medical Association [1]. The CATIS study was a multicenter, controlled, randomized study that aimed to assess the effects of blood pressure reduction during the acute phase of ischemic stroke on death and major disability at 14 days and 3 months after the episode. The stroke was confirmed by brain CT or MRI and systolic blood pressure levels between 140-220 mmHg were required to enter the study. About half of screened patients with an acute ischemic stroke and hypertension fulfilled all inclusion/exclusion criteria and entered the study (2,038 out of 4,071).

Study participants were randomly assigned to receive or not antihypertensive therapy within 48 hours of stroke onset. In particular, a graded blood pressure reduction was aimed in the active group targeting a 10-25% reduction during the first study day and blood pressure control during the first week post-randomization. In contrast, no antihypertensive therapy was given in the control group and previous antihypertensive medication was discontinued during the acute phase of stroke. After the first week, all patients received antihypertensive therapy to achieve blood pressure control (<140/90 mmHg).

Blood pressure was significantly reduced in both groups during the first 24h post-randomization; however, the reduction was significantly greater in the active compared to the control group (21.8 versus 12.7 mmHg; between group difference: 9.1 mmHg; 95% CI: 8.1-10.2; p<0.001). Similarly, blood pressure levels were significantly lower in the active group at 7 days post-randomization (between group difference 9.3 mmHg; 95% CI: 8.4-10.1; p<0.001). The primary outcome (death or major disability at 14 days or hospital discharge) was identical in the two groups (odds ratio: 1.00; 95% CI: 0.88-1.14; p=0.98). The secondary outcome (death or major disability at 3 months post-randomization) was also the same (odds ratio: 0.99; 95% CI: 0.86-1.15; p=0.93), despite lower blood pressure values in the active group.

Subgroup analysis did not reveal any significant differences between the two groups on study outcomes. Blood pressure reduction during the acute phase of stroke seemed to confer a significant benefit only in one subgroup of patients: those who received antihypertensive therapy after the first 24h of stroke onset (odds ratio: 0.73; 95% CI: 0.55- 0.97; p=0.03). It has to be noted however that the findings of the subgroup analysis should always interpreted with caution, and be considered rather as hypothesis generating than conclusive.

The results of the CATIS study add more gas on the debate about the management of elevated blood pressure during the acute phase of an ischemic stroke. Current guidelines recommend blood pressure lowering in acute ischemic stroke only when blood pressure levels are above 220/120 mmHg [2]. However, such patients represent a minority, with less of 1% of patients admitted for stroke [3]. Therefore, a therapeutic strategy for the vast majority of stroke patients with elevated blood pressure is of utmost importance for practicing clinicians.

Available data in this field is unfortunately limited and inconclusive. About a decade ago, the Acute Candesartan Cilexitil Therapy in Stroke Survivors (ACCESS) study created a lot of enthusiasm [4]. A significantly lower rate of vascular events and all-cause mortality at 12 months was observed with candesartan compared to placebo (odds ratio: 0.475; 95% CI: 0.252-0.895), and the study was prematurely terminated when almost 350 patients were randomized instead of the projected 500 patients.

The ACCESS study questioned the negative findings of the Intravenous Nimodipine West European Stroke Trial (INWEST) [5], and set the basis for the conduction of a larger study, the Scandinavian Candesartan Acute Stroke Trial (SCAST). In the latter study, candesartan was compared to placebo in more than 2,000 patients with acute stroke, either ischemic or hemorrhagic [6]. Unfortunately, the great expectations generated by the ACCESS study were not fulfilled. There was no significant difference in the outcome between the active and the placebo group of the trial.

In the meantime, two other smaller studies were published. The Controlling Hypertension and Hypotension Immediately Post-Stroke (CHHIPS), a placebo-controlled, randomized study of 179 patients with acute stroke compared the effects of labetalol, lisinopril, and placebo [7]. No significant differences between the active and the comparison groups were observed, apart from a marginal benefit in mortality at 3 months post-stroke (hazard ratio: 0.40; 95% CI: 0.2-1.0; p=0.05). The Continue or Stop Post-Stroke Antihypertensives Collaborative Study (COSSACS) compared the effects of continuation or withdrawal of prior antihypertensive therapy in 763 patients with an acute mild stroke [8]. Continuation of antihypertensive therapy did not confer any benefit in mortality or disability.

Taken together, the findings of the CATIS trial combined with the findings of previous trials point towards a neutral effect of antihypertensive therapy during the acute phase of an ischemic stroke. Whether the time of therapy initiation (>24h from stroke onset) or other yet unidentified factors play a role and might identify patient subgroups who will benefit from antihypertensive therapy remains to be clarified by future research. Until then, the ‘non-detrimental – nonbeneficial’ effect of antihypertensive therapy suggests the individualization of management during the acute stroke by treating physicians.

CONGRESS COVERAGE: Renal Sympathetic Denervation for Resistant Hypertension: Symplicity HTN-3 and the Power of Placebo

DEAR EDITOR

The results of the Symplicity HTN-3 trial have been presented a few days ago in the 2014 Scientific Meeting of the American College of Cardiology and simultaneously published in the New England Journal of Medicine [1]. The Symplicity HTN-3 trial was the first placebo-controlled (via sham procedure) study evaluating the effects of renal sympathetic denervation (RSD) in patients with resistant hypertension. The study met its primary safety endpoint but failed to achieve its primary and secondary efficacy endpoints generating major disappointment in the scientific community and raised significant concerns about the future of this novel interventional approach for the management of patients with resistant hypertension.

The Symplicity HTN-3 trial was a multicenter, prospective, randomized, single-blind, sham-controlled study conducted in the United States of America. The study was performed in patients with uncontrolled resistant hypertension, i.e. office systolic blood pressure >160 mmHg despite the use of at least three antihypertensive drugs (one of which was a diuretic) in maximally tolerated doses. Moreover, home blood pressure monitoring for two weeks and 24h ambulatory blood pressure monitoring ensured the diagnosis of true resistant hypertension, excluding patients with pseudoresistance due to the white-coat effect. From a total of 1,441 patients screened for eligibility, 535 patients fulfilled the inclusion/criteria and were randomly assigned to either RSD or a sham procedure (placebo) in a 2 to 1 ratio and were then followed-up for 6 months.

The primary safety endpoint was a composite of hard and surrogate events (all-cause mortality, end-stage renal failure, embolic episodes leading to target organ damage, renovascular complications and new-onset renal artery stenosis, and hypertensive crises) less of approximately 10%, based on prior information. The office blood pressure reduction at 6 months with a superiority margin of 5 mmHg for renal nerve ablation was the primary efficacy endpoint and the ambulatory blood pressure reduction at the same time point was the secondary efficacy endpoint.

The study achieved its primary safety endpoint, since no significant differences in adverse events were observed between RSD and sham procedure. In total, there were 5 significant adverse events in the active treatment group compared with one significant adverse event in the placebo group, and the difference was not significant (p=0.67). Moreover, no significant deterioration of renal function was observed with RSD, even in patients with chronic kidney disease (estimated glomerular filtration rate < 60 ml/min/1.73m2). The reassuring renal safety profile confirms the short-term safety of RSD that was observed in previous studies [2-5], but does not totally exclude potential long-term detrimental effects on renal function [6, 7].

The major disappointment however comes from the efficacy endpoints. The study failed to achieve both its primary and secondary efficacy endpoints. In particular, the mean reduction in office blood pressure was 14.1 mmHg with active therapy and 11.7 mmHg with placebo at 6 months, and was highly significant for both groups compared to baseline (p<0.001). However, the between-group difference in systolic blood pressure reduction was small (2.4 mmHg) and was not significant (p=0.26) in terms of the pre-defined superiority of 5 mmHg. Similarly, the mean reduction in ambulatory blood pressure at 6 months was 6.8 mmHg with active therapy and 4.8 mmHg with placebo compared to baseline, and the small between-group difference (2.0 mmHg) was not significant (p=0.98) for a superiority margin of 2 mmHg.

Several points need to be highlighted and evaluated in the context of previous knowledge in order to avoid misleading conclusion.

Firstly, the magnitude of office blood pressure reduction was almost half than in previous studies (14.1 mmHg versus 25-30 mmHg) [2, 3, 5, 8-11]. The inferior efficacy of RSD in the Symplicity-3 might be attributed to differences in study populations and several other factors. It has to be noted however that all previous studies were uncontrolled. It has been estimated that the anticipated blood pressure reduction with RSD is approximately 15 mmHg, when all other factors are taken in consideration [12].

Secondly, the ambulatory blood pressure reduction was significantly lower than the office blood pressure reduction (6.8 mmHg versus 14.1 mmHg), and this also was not an unexpected finding. A marked disparity between office and ambulatory blood pressure reduction with RSD has been observed in all previous RSD studies [13], and this disparity is significantly higher than with antihypertensive drug therapy [14].

Thirdly, the main factor contributing to the negative findings of the study was the impressive blood pressure reduction with the sham procedure (11.7 mmHg). However, this was also not an unexpected finding and it should have been anticipated based on previous data. Indeed, two studies performed in patients with resistant hypertension and similar baseline characteristics, revealed a strong placebo effect: the Rheos pivotal trial and the darusentan study [15, 16]. The powerful placebo effect almost “killed” both carotid baroreceptor activation and endothelin receptor antagonism for the treatment of resistant hypertension [17, 18].

Finally, potential disadvantages in study design cannot be entirely excluded. The study design was very meticulous and of the highest quality, and included sham procedure and ambulatory blood pressure monitoring overcoming previous concerns [19, 20]. However, one factor might have significantly influenced the findings of the study: the absence of familiarity with this novel procedure. The study was conducted in 88 sites all over the United States and more than 100 interventional cardiologists performed the procedure, for a mean of 3 to 4 procedures for each interventionalist. This raises the concern of a learning curve, especially because RSD was performed with the single-tip Symplicity catheter, which needs a lot of manipulations.

Overall, the negative findings of the Symplicity-3 trial “turned-off” the initial enthusiasm about RSD in many physicians, both hypertension specialists and primary care doctors. However, a sober and dispassionate approach seems more rational, avoiding overwhelming enthusiasm and excessive pessimism. Carefully designed clinical trials along with intensive research about response predictors are eagerly awaited in order to identify patient subgroups that will benefit from RSD.

EDITORIAL: No-Pharmacological Intervention: Pomegranate Juice for the Management of Hypertension and the Improvement of Cardiovascular Health

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Unresolved issues in lipid-lowering treatment

Elevated low-density lipoprotein cholesterol (LDL-C) levels are a major modifiable risk factor for cardiovascular disease (CVD). In addition, treatment with statins reduces cardiovascular morbidity and mortality both in patients without and with established CVD. However, there still exist unresolved issues in the management of dyslipidemia. First, which are the optimal LDL-C levels? Second, do low high-density lipoprotein cholesterol (HDL-C) levels play a role in the pathogenesis of atherosclerosis and should they also represent treatment targets? In the present review, we discuss these two pertinent questions. Accumulating data, both from observational studies and from interventional studies with statins and other lipid-lowering agents, suggest that lowering LDL-C levels considerably below the currently recommended targets is both safe and further reduces cardiovascular morbidity and mortality. These benefits are particularly relevant for patients at very high cardiovascular risk, i.e. those with established CVD. On the other hand, it is questionable whether HDL-C is causally related to atherosclerosis and whether increasing HDL-C levels will translate into reduced cardiovascular risk. This uncertainty is even more pronounced in patients who achieve very low LDL-C levels with statin treatment.

Clinical controversies in lipid management

Even though it is firmly established that statins are the cornerstone of management of dyslipidemias, several controversies still exist in this area. In the present review, the most pertinent controversies in lipid management are discussed and the current evidence is summarized. Treatment with statins increases the risk for type 2 diabetes mellitus (T2DM) but this increase appears to be small and outweighed by the benefits of statins on cardiovascular disease prevention. Accordingly, statin treatment-associated T2DM should not affect management decisions. In patients who cannot achieve low-density lipoprotein cholesterol (LDL-C) targets despite treatment with the maximum tolerated dose of a potent statin, adding ezetimibe appears to be the treatment of choice. Finally, patients who achieved LDL-C targets with a statin but have elevated triglyceride levels appear to have increased cardiovascular risk and adding fenofibrate appears to reduce this risk. Even though additional large randomized controlled trials are unlikely to be performed with the existing lipid-lowering agents, mechanistic, genetic and epidemiological studies, as well as careful analyses of the existing trials will provide further insights in these controversial issues and will allow the optimization of the management of dyslipidemia aiming at further reductions in cardiovascular morbidity.

Persistent effect of zoledronic acid in Paget's disease

Paget's bone disease is a disorder in which bone regions with high turnover are replaced by new, vascular, but disorganized and immature bone with excessive fibrosis, high tendency of deformity and diminished mechanical resistance. Treatment aims at the suppression of osteoclast activity and is achieved with bisphosphonates, which represent the treatment of choice for Paget's disease. Zoledronic acid, a relatively new member of this class, normalizes alkaline phosphatase in the majority of patients and has a favorable safety profile. We report the case of an asymptomatic patient who was diagnosed with Paget's disease based on typical biochemical, radiological and histological findings and was treated with a single intravenous infusion of 4 mg of zoledronic acid. No side effects were observed. Alkaline phosphatase levels normalized within four months. At the last follow up examination, three years after treatment, the patient remains asymptomatic, without significant changes in radiology imaging, and alkaline phosphatase levels are still within the normal range. In conclusion, zoledronic acid, apart from being safe and effective in Paget's disease, also appears to be able to achieve significantly prolonged remissions.

Increased risk of vascular events in systemic lupus erythematosus: is arterial stiffness a predictor of vascular risk?

Patients with systemic lupus erythematosus (SLE) have an increased vascular morbidity and mortality. Several established vascular risk factors are more prevalent in this population but cannot fully explain the reported excess atherosclerotic burden. Emerging vascular risk factors may also contribute to the increased vascular risk in these patients although the evidence is limited and often conflicting. SLE-specific risk factors also play a role in the pathogenesis of atherosclerosis.Given the multifactorial aetiology of vascular disease in SLE, an integrated index of risk could be useful in the management of these patients. Arterial stiffness possibly represents such an index and accumulating data suggest an increased prevalence of arterial stiffness in SLE. Many factors play a role in the loss of arterial elasticity in this population, including both emerging and established vascular risk factors. Arterial stiffness may emerge as a useful index for risk stratification in SLE and has the potential to guide therapeutic decisions in these patients.