Calcium channel blockers for preventing cardiomyopathy due to iron overload in people with transfusion-dependent beta thalassaemia.

BACKGROUND: Beta-thalassaemia is an inherited blood disorder that reduces the production of haemoglobin. The most severe form requires recurrent blood transfusions, which can lead to iron overload. Cardiovascular dysfunction caused by iron overload is the leading cause of morbidity and mortality in people with transfusion-dependent beta-thalassaemia. Iron chelation therapy has reduced the severity of systemic iron overload, but removal of iron from the myocardium requires a very proactive preventive strategy. There is evidence that calcium channel blockers may reduce myocardial iron deposition. This is an update of a Cochrane Review first published in 2018. OBJECTIVES: To assess the effects of calcium channel blockers plus standard iron chelation therapy, compared with standard iron chelation therapy (alone or with a placebo), on cardiomyopathy due to iron overload in people with transfusion-dependent beta thalassaemia. SEARCH METHODS: We searched the Cochrane Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books, to 13 January 2022. We also searched ongoing trials databases and the reference lists of relevant articles and reviews. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of calcium channel blockers combined with standard chelation therapy versus standard chelation therapy alone or combined with placebo in people with transfusion-dependent beta thalassaemia. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. We used GRADE to assess certainty of evidence. MAIN RESULTS: We included six RCTs (five parallel-group trials and one cross-over trial) with 253 participants; there were 126 participants in the amlodipine arms and 127 in the control arms. The certainty of the evidence was low for most outcomes at 12 months; the evidence for liver iron concentration was of moderate certainty, and the evidence for adverse events was of very low certainty. Amlodipine plus standard iron chelation compared with standard iron chelation (alone or with placebo) may have little or no effect on cardiac T2* values at 12 months (mean difference (MD) 1.30 ms, 95% confidence interval (CI) -0.53 to 3.14; 4 trials, 191 participants; low-certainty evidence) and left ventricular ejection fraction (LVEF) at 12 months (MD 0.81%, 95% CI -0.92% to 2.54%; 3 trials, 136 participants; low-certainty evidence). Amlodipine plus standard iron chelation compared with standard iron chelation (alone or with placebo) may reduce myocardial iron concentration (MIC) after 12 months (MD -0.27 mg/g, 95% CI -0.46 to -0.08; 3 trials, 138 participants; low-certainty evidence). The results of our analysis suggest that amlodipine has little or no effect on heart T2*, MIC, or LVEF after six months, but the evidence is very uncertain. Amlodipine plus standard iron chelation compared with standard iron chelation (alone or with placebo) may increase liver T2* values after 12 months (MD 1.48 ms, 95% CI 0.27 to 2.69; 3 trials, 127 participants; low-certainty evidence), but may have little or no effect on serum ferritin at 12 months (MD 0.07 µg/mL, 95% CI -0.20 to 0.35; 4 trials, 187 participants; low-certainty evidence), and probably has little or no effect on liver iron concentration (LIC) after 12 months (MD -0.86 mg/g, 95% CI -4.39 to 2.66; 2 trials, 123 participants; moderate-certainty evidence). The results of our analysis suggest that amlodipine has little or no effect on serum ferritin, liver T2* values, or LIC after six months, but the evidence is very uncertain. The included trials did not report any serious adverse events at six or 12 months of intervention. The studies did report mild adverse effects such as oedema, dizziness, mild cutaneous allergy, joint swelling, and mild gastrointestinal symptoms. Amlodipine may be associated with a higher risk of oedema (risk ratio (RR) 5.54, 95% CI 1.24 to 24.76; 4 trials, 167 participants; very low-certainty evidence). We found no difference between the groups in the occurrence of other adverse events, but the evidence was very uncertain. No trials reported mortality, cardiac function assessments other than echocardiographic estimation of LVEF, electrocardiographic abnormalities, quality of life, compliance with treatment, or cost of interventions. AUTHORS' CONCLUSIONS: The available evidence suggests that calcium channel blockers may reduce MIC and may increase liver T2* values in people with transfusion-dependent beta thalassaemia. Longer-term multicentre RCTs are needed to assess the efficacy and safety of calcium channel blockers for myocardial iron overload, especially in younger children. Future trials should also investigate the role of baseline MIC in the response to calcium channel blockers, and include a cost-effectiveness analysis.

Natural products as the calcium channel blockers for the treatment of arrhythmia: Advance and prospect.

Arrhythmia is one of the commonly heart diseases with observed abnormal heart-beat rhythm that caused by the obstacles of cardiac activity and conduction. The arrhythmic pathogenesis is complex and capricious and related with other cardiovascular diseases that may lead to heart failure and sudden death. In particular, calcium overload is recognized as the main reason causing arrhythmia through inducing apoptosis in cardiomyocytes. Moreover, calcium channel blockers have been widely used as the routine drugs for the treatment of arrhythmia, but the different arrhythmic complications and adverse effects limit their further applications and demand new drug discovery. Natural products have always been the rich minerals for the development of new drugs that could be employed as the versatile player for the discovery of safe and effective anti-arrhythmia drugs with new mechanisms. In this review, we summarized natural products with the activity against calcium signaling and the relevant mechanism of actions. We are expected to provide an inspiration for the pharmaceutical chemists to develop more potent calcium channel blockers for the treatment of arrhythmia.

Association between clinical use of nifedipine and the risk of osteoporosis: a nationwide retrospective cohort study.

Nifedipine is one of the common calcium channel blockers (CCBs) for hypertension that induce peroxisome-proliferator-activated receptor γ coactivator 1-α, which is envisioned as a potential therapeutic target in bone disease. The findings of this retrospective cohort study suggest that patients who receive nifedipine may have a potential protective effect on osteoporosis in comparison to other CCBs. INTRODUCTION: Nifedipine was one L-type dihydropyridine calcium channel blocker (CCB) that can improve bone loss. However, epidemiological studies on the association between the use of nifedipine and osteoporosis risk are limited. Thus, this study aimed to evaluate the association between the clinical use of nifedipine and the risk of osteoporosis. METHODS: This retrospective cohort was conducted using the National Health Insurance Research Database of Taiwan from 2000 to 2013. The study includes 1225 patients receiving nifedipine (the exposed cohort) and 4900 patients receiving other CCBs (the comparison cohort). The primary outcome was the diagnosis of osteoporosis. The hazard ratios (HRs) and 95% confidence intervals (CIs) were used to assess the association between the use of nifedipine and the risk of osteoporosis. RESULTS: Patients receiving nifedipine treatment had a reduced risk of osteoporosis as compared with those undergoing other CCB treatments (adjusted HR, 0.44; 95% CI, 0.37-0.53). Moreover, this inverse association is evident in both sexes and various age groups. CONCLUSIONS: This population-based cohort study demonstrated that nifedipine may have potential protective effect on osteoporosis compared with other CCBs. The clinical implications of the present study need further investigation.

Comparative peripheral edema for dihydropyridines calcium channel blockers treatment: A systematic review and network meta-analysis.

Dihydropyridine calcium channel blockers (DHPCCBs) are widely used to treat hypertension and chronic coronary artery disease. One common adverse effect of DHPCCBs is peripheral edema, particularly of the lower limbs. The side effect could lead to dose reduction or discontinuation of the medication. The combination of DHPCCBs and renin-angiotensin system blockers has shown to reduce the risk of DHPCCBs-associated peripheral edema compared with DHPCCBs monotherapy. We performed the current systematic review and network meta-analysis of randomized controlled trials (RCTs) to estimate the rate of peripheral edema with DHPCCBs as a class and with individual DHPCCBs and the ranking of the reduction of peripheral edema. The effects of renin-angiotensin system blockers on DHPCCBs network meta-analysis were created to analyze the ranking of the reduction of peripheral edema. A total of 3312 publications were identified and 71 studies with 56,283 patients were included. Nifedipine ranked highest in inducing peripheral edema (SUCRA 81.8%) and lacidipine (SUCRA 12.8%) ranked the least. All DHPCCBs except lacidipine resulted in higher relative risk (RR) of peripheral edema compared with placebo. Nifedipine plus angiotensin receptor blocker (SUCRA: 92.3%) did not mitigate peripheral edema and amlodipine plus angiotensin-converting enzyme inhibitors (SUCRA: 16%) reduced peripheral edema the most. Nifedipine ranked the highest and lacidipine ranked the lowest amongst DHPCCBs for developing peripheral edema when used for cardiovascular indications. The second or higher generation of DHPCCBs combination with ACEIs or ARBs or diuretics lowered the chance of peripheral edema development compared to single DHPCCB treatment.

Dyskalemia risk associated with fixed-dose anti-hypertensive medication combinations.

A model-based meta-analysis quantified comparative dyskalemia risk (hyper- or hypo-kalemia) in hypertensive patients treated with angiotensin receptor blockers (ARBs), a calcium channel blocker (CCB) and/or a thiazide diuretic (hydrochlorothiazide; HCTZ) as monotherapy or as fixed-dose combinations. Among 15 randomized controlled trials in a US Food and Drug Administration regulatory review database, dyskalemia events were reported by five trials (24 treatment arms, 11,030 subjects, 8-week median follow up time). The five trials evaluated monotherapy (ARB or HCTZ) alongside dual (ARB + HCTZ, ARB + CCB, or HCTZ + CCB) or triple fixed-dose combinations (ARB + CCB + HCTZ). Hypo- and hyper-kalemia rates were analyzed jointly to account for correlation. Significant drug class, drug, or dose effects were included in the final model. Effect on various drug- and dose combinations on dyskalemia risk were simulated and compared with model-estimated placebo arm dyskalemia risk. After a typical follow-up of 8 weeks, fixed-dose combinations of ARB with a high dose (25 mg) of HCTZ were associated with a higher hypokalemia risk difference (RD) from placebo (e.g.,Valsartan + HCTZ: 2.52%[95%CIs:1.17, 4.38%]). However, when ARB was combined with a lower, 12.5 mg dose of HCTZ, hypokalemia RD from placebo was not significant (Valsartan + HCTZ: -0.03%[-0.80, 0.71%]). ARB monotherapy raised hyperkalemia RD from placebo (1.3%[0.3, 3.6%]). Hyperkalemia risk was not appreciably higher than placebo for any FDC that combined ARB with HCTZ (Valsartan + HCTZ: 0.06%[-1.48, 1.64%]). In uncomplicated hypertensive patients, ARB + 12.5 mg HCTZ fixed-dose combinations are safer with respect to dyskalemia than either ARB or HCTZ monotherapy for initial antihypertensive treatment.

Auxora for the Treatment of Patients With Acute Pancreatitis and Accompanying Systemic Inflammatory Response Syndrome: Clinical Development of a Calcium Release-Activated Calcium Channel Inhibitor.

OBJECTIVES: To assess the safety of Auxora in patients with acute pancreatitis (AP), systemic inflammatory response syndrome (SIRS), and hypoxemia, and identify efficacy endpoints to prospectively test in future studies. METHODS: This phase 2, open-label, dose-response study randomized patients with AP, accompanying SIRS, and hypoxemia (n = 21) to receive low-dose or high-dose Auxora plus standard of care (SOC) or SOC alone. All patients received pancreatic contrast-enhanced computed tomography scans at screenings, day 5/discharge, and as clinically required 90 days postrandomization; scans were blinded and centrally read to determine AP severity using computed tomography severity index. Solid food tolerance was assessed at every meal and SIRS every 12 hours. RESULTS: The number of patients experiencing serious adverse events was not increased with Auxora versus SOC alone. Three (36.5%) patients with moderate AP receiving low-dose Auxora improved to mild AP; no computed tomography severity index improvements were observed with SOC. By study end, patients receiving Auxora better tolerated solid foods, had less persistent SIRS, and had reduced hospitalization versus SOC. CONCLUSIONS: The favorable safety profile and patient outcomes suggest Auxora may be an appropriate early treatment for patients with AP and SIRS. Clinical development will continue in a randomized, controlled, blinded, dose-ranging study.

Pharmacological hypothesis: TPC2 antagonist tetrandrine as a potential therapeutic agent for COVID-19.

More than ten million patients worldwide have been diagnosed with coronavirus disease 19 (COVID-19) to date (WHO situation report, 1st July 2020). There is no vaccine to prevent infection with the causative organism, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), nor a cure. In the struggle to devise potentially useful therapeutics in record time, the repurposing of existing compounds is a key route of action. In this hypothesis paper, we argue that the bisbenzylisoquinoline and calcium channel blocker tetrandrine, originally extracted from the plant Stephania tetrandra and utilized in traditional Chinese medicine, may have potential in the treatment of COVID-19 and should be further investigated. We collate and review evidence for tetrandrine's putative mechanism of action in viral infection, specifically its recently discovered antagonism of the two-pore channel 2 (TPC2). While tetrandrine's particular history of use provides a very limited pharmacological dataset, there is a suggestion from the available evidence that it could be effective at doses used in clinical practice. We suggest that further research to investigate this possibility should be conducted.

Clinical efficacy of various anti-hypertensive regimens in hypertensive women of Punjab; a longitudinal cohort study.

BACKGROUND: Gender wise differences exist in anti-hypertensive treatment outcomes, yet still un-explored in Pakistan. Thus, we aimed to estimate the clinical efficacy of four different anti-hypertensive regimens in hypertensive women of Punjab, Pakistan. METHODS: A longitudinal cohort study of 12 months duration was conducted by enrolling 300 hypertensive women on four anti-hypertensive regimens. Chi-square for significance, logistic regression for association and multilevel regression for changes in outcomes were used. RESULTS: Majority of subjects were < 60 years of age, weighing > 65 Kg, having family history, married and hailing from urban areas, with diabetes as the most common comorbidity. Hypertension, adjusted for covariates, was significantly associated with salt intake (OR:2.27, p <  0.01) and physical activity (OR;2.16, p <  0.01). High-risk subjects, compared to low-risk, were consuming more fat (OR;1.54), meat (OR; 2), salt (OR; 2.48) and even vegetables/fruits (OR;3.43). Compared to baseline, the maximum reduction in BP was observed with combination therapy, N-GITS+LTN + HCT (SBP; - 50.17, p <  0.01, DBP; - 16.55, p <  0.01), followed by N-GITS alone (SBP; - 28.89, p <  0.01, DBP; - 12.21, p <  0.01). Compared to baseline, adjusted for treatment effects, significant reductions in SBP (low-risk; - 17.92, p <  0.01 high-risk; - 19.48, p <  0.01) and DBP (low-risk; - 17.92, p <  0.01, high-risk; - 19.48, p <  0.01) were observed in low and high risk patients. Among all four cohorts, orthostatic hypotension and edema were common in N-GITS+LTN + HCT only, but variable effects were observed on biochemical values; urea, BSR and creatinine. CONCLUSION: In conclusion, compared to a single agent, combination therapy conferred improved BP controls followed by N-GITS alone in low and high risk women with manageable side effects.

Retinal teratogenicity of pregabalin in chick embryo model.

BACKGROUND: Pregabalin is a gamma-aminobutyric acid analog that binds to the α2-δ subunits of the pre-synaptic voltage-dependent calcium channels of nerves with a high affinity and selectivity. In this study, the retinal teratogenic potential of pregabalin was investigated in a chick embryo model. MATERIALS AND METHODS: Fertilised chicken eggs were divided into groups for administration with different doses of pregabalin. All eggs were opened on the 10th day of incubation. The embryos were dissected and the effects of pregabalin on the retina were investigated histopathologically, morphometrically, and immunohistochemically (Caspase-3). RESULTS: There was no statistically significant difference between the low dose pregabalin, control, or vehicle control groups in terms of the number of retina layers and retinal thickness. Medium and high dose pregabalin caused a statistically significant decrease in the number of retina layers, as well as sensory retinal and pigment epithelium layer thicknesses. The outer nuclear and outer plexiform layer did not form in the group administered a medium dose. Similarly, the outer nuclear, outer plexiform, inner nuclear, and inner plexiform layer did not form in the high-dose group. No statistically significant difference was observed between the groups in terms of cellular damage and Caspase-3 expression. CONCLUSION: The use of pregabalin during pregnancy compromises retinal development in a dose-dependent manner. The use of pregabalin in pregnancy causes the aforementioned defects in this system and it may have developmental effects that needs to be further evaluated.

Calcium Channel Blockers in Conjunction with Standard Iron-Chelating Agents for ß-Thalassemia Major: Systematic Literature Search.

Thalassemia is a genetic mutation of the α- or ß-globin chains that lead to defective erythropoiesis. This study aimed to collect evidences from all published studies that investigated the clinical effectiveness of calcium channel blockers (CCBs) in conjunction with chelation therapy for reducing iron overload in patients with thalassemia. A systematic search was conducted in PubMed, Institute for Scientific Information (ISI) Web of Science, Scopus, Cochrane Central Register of Controlled Trials, and Virtual Health Library. Original studies reporting the use of CCBs in patients with thalassemia were included for meta-analysis. A total of five randomized studies including 210 patients were included with a follow-up period of 3-12 months. There was no significant difference between amlodipine and control groups in increasing the heart T2* magnetic resonance imaging (MRI) [mean difference (MD) 95% confidence interval (95% CI) = -1.9 (-4.4 to 0.5), p = 0.119] or reducing the liver iron concentration [MD 95% CI = -0.046 (-0.325 to 0.2), p = 0.746]. Although there were no serious adverse events reported in the included trials, further studies are recommended to strengthen our findings.

Therapeutic effect of piracetam with nimodipine on vascular dementia after cerebral infarction.

This article investigated the clinical effects of piracetam with nimodipine in the treatment of vascular dementia (VD) after cerebral infarction. 98 patients with vascular dementia after cerebral infarction were selected and divided into the control group and the study group according to the treatment method. The control group was treated with nimodipine alone. The study group was treated with piracetam on the basis of this observation, and we test the ADL (life ability score), MoCA(montreal cognitive assessment scale), ADAS-Cog(alzheimer's scale-cognition), MMSE(mental status examination) scores and quality of life scores before and after treatment in the two groups. Before treatment, there were no significant differences in ADL, MoCA, and ADAS-Cog scores between the two groups (P>0.05). After treatment, the ADL, MoCA, and ADAS-Cog scores of the study group were superior to the control group. The difference was statistically significant (P<0.05). There was no significant difference in MMSE scores between the two groups before treatment and 1 month after treatment (P>0.05). The MMSE scores of the study group were better than the control group after 3 months of treatment and half a year after treatment. The difference was statistically significant (P <0.05). Before treatment, there was no significant difference in the quality of life scores between the two groups (P>0.05). After treatment, the quality of life scores was significantly higher than the control group, and the difference was statistically significant (P<0.05). For patients with vascular dementia after cerebral infarction, piracetam combined with nimodipine can improve the cognitive function, improve the quality of life, and have a significant clinical effect.

Differential effects on out-of-hospital cardiac arrest of dihydropyridines: real-world data from population-based cohorts across two European countries.

AIMS: Various drugs increase the risk of out-of-hospital cardiac arrest (OHCA) in the general population by impacting cardiac ion channels, thereby causing ventricular tachycardia/fibrillation (VT/VF). Dihydropyridines block L-type calcium channels, but their association with OHCA risk is unknown. We aimed to study whether nifedipine and/or amlodipine, often-used dihydropyridines, are associated with increased OHCA risk, and how these drugs impact on cardiac electrophysiology. METHODS AND RESULTS: We conducted a case-control study with VT/VF-documented OHCA cases with presumed cardiac cause from ongoing population-based OHCA registries in the Netherlands and Denmark, and age/sex/index date-matched non-OHCA controls (Netherlands: PHARMO Database Network, Denmark: Danish Civil Registration System). We included 2503 OHCA cases, 10 543 non-OHCA controls in Netherlands, and 8101 OHCA cases, 40 505 non-OHCA controls in Denmark. To examine drug effects on cardiac electrophysiology, we performed single-cell patch-clamp studies in human-induced pluripotent stem cell-derived cardiomyocytes. Use of high-dose nifedipine (≥60 mg/day), but not low-dose nifedipine (<60 mg/day) or amlodipine (any-dose), was associated with higher OHCA risk than non-use of dihydropyridines [Netherlands: adjusted odds ratios (ORadj) 1.45 (95% confidence interval 1.02-2.07), Denmark: 1.96 (1.18-3.25)] or use of amlodipine [Netherlands: 2.31 (1.54-3.47), Denmark: 2.20 (1.32-3.67)]. Out-of-hospital cardiac arrest risk of (high-dose) nifedipine use was not further increased in patients using nitrates, or with a history of ischaemic heart disease. Nifedipine and amlodipine blocked L-type calcium channels at similar concentrations, but, at clinically used concentrations, nifedipine caused more L-type calcium current block, resulting in more action potential shortening. CONCLUSION: High-dose nifedipine, but not low-dose nifedipine or any-dose amlodipine, is associated with increased OHCA risk in the general population. Careful titration of nifedipine dose should be considered.

Acute calcium channel blocker withdrawal-induced cardiac arrest.

Acute withdrawal of calcium channel blockers can lead to the so-called calcium channel blocker withdrawal phenomenon, in particular, when high dosages are used. In the case presented, inadequate drug substitution led to this phenomenon which resulted in a serious course of events. Careful monitoring the process of drug substitution with respect to equal therapeutic dosages is therefore a necessity, especially in vulnerable patients.

Magnitude of and Characteristics Associated With the Treatment of Calcium Channel Blocker-Induced Lower-Extremity Edema With Loop Diuretics.

Importance: Calcium channel blockers, specifically dihydropyridine calcium channel blockers (DH CCBs, eg, amlodipine), may cause lower-extremity edema. Anecdotal reports suggest this may result in a prescribing cascade, where DH CCB-induced edema is treated with loop diuretics. Objective: To assess the magnitude and characteristics of the DH CCB prescribing cascade. Design, Setting, and Participants: This cohort study used a prescription sequence symmetry analysis to assess loop diuretic initiation before and after the initiation of DH CCBs among patients aged 20 years or older without heart failure. Data from a private insurance claims database from 2005 to 2017 was analyzed. Use of loop diuretics associated with initiation of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and other commonly used medications was used as negative controls. Data were analyzed from March 2019 through October 2019. Exposures: Initiation of DH CCB or negative control medications. Main Outcomes and Measures: The temporality of loop diuretic initiation relative to DH CCB or negative control initiation. Secular trend-adjusted sequence ratios (aSRs) with 95% CIs were calculated using data from 360 days before and after initiation of DH CCBs. Results: Among 1 206 093 DH CCB initiators, 55 818 patients (4.6%) (33 100 [59.3%] aged <65 years; 32 916 [59.0%] women) had a new loop diuretic prescription 360 days before or after DH CCB initiation, resulting in an aSR of 1.87 (95% CI, 1.84-1.90). An estimated 1.44% of DH CCB initiators experienced the prescribing cascade. The aSR was disproportionately higher among DH CCB initiators who were prescribed high doses (aSR, 2.20; 95% CI, 2.13-2.27), initiated amlodipine (aSR, 1.89; 95% CI, 1.86-1.93), were men (aSR, 1.96; 95% CI, 1.91-2.01), and used fewer antihypertensive classes (aSR, 2.55; 95% CI, 2.47-2.64). The evaluation of ACE inhibitors or ARBs as negative controls suggested hypertension progression may have tempered the incidence of the prescribing cascade (aSR for ACE inhibitors and ARBs, 1.27; 95% CI, 1.24-1.29). Conclusions and Relevance: This study found an excessive use of loop diuretics following initiation of DH CCBs that cannot be completely explained by secular trends or hypertension progression. The prescribing cascade was more pronounced among those initially prescribed a high dose of DH CCBs.

Anti-hypertensive efficacy of amlodipine dosing during morning versus evening: A meta-analysis.

A meta-analysis was performed to compare the antihypertensive efficacy of morning and evening dosing. Database of Pubmed, Embase, Cochrane, Web of Science CNKI, VIP, and Wanfang were searched up to December 2018. A total of 19 randomized control trials and 1215 participants were included in this meta-analysis. Administration time of amlodipine did not affect the office blood pressure (RR = -0.03, 95% CI -0.93-0.88, P = 0.96), daytime blood pressure (RR = -0.30, 95% CI -1.05-0.46, P = 0.44), 24 h mean blood pressure (RR = 1.15, 95% CI -0.39-2.70, P = 0.14), or heart rate (RR = 0.11, 95% CI -1.22-1.45, P = 0.87). Administration of amlodipine in the evening could significantly reduce the nighttime blood pressure (RR = 2.04, 95% CI 1.27-2.81, P < 0.00001), increased non-dipper alteration (RR = 0.51, 95% CI 0.41-0.63, P < 0.00001), and contained better anti-hypertension efficacy (RR = 0.64, 95% CI 0.55-0.74, P < 0.00001). For patients with hypertension, especially for non-dipper hypertension, taking amlodipine in the evening will be more beneficial. Better quality trials conducted in different regions and with larger sample size are necessary to verify the conclusion of this study.

A 'Natural' thyroid storm!

WHAT IS KNOWN AND OBJECTIVE: Over the counter supplements are often taken for granted during medication reconciliation in the emergency department. Supplements are not regulated by FDA, and some can be potentially dangerous. CASE SUMMARY: We report a case of thyrotoxicosis secondary to over the counter bovine thyroid supplements. Our patient presented with atrial fibrillation with rapid ventricular response refractory to calcium channel blockers. Had we not known about the supplement, the course of treatment would have been different with potential adverse outcome. WHAT IS NEW AND CONCLUSION: Natural thyroid supplements are marketed as over the counter products and are largely unregulated. Thyroid extracts have been found to have disparaging inconsistencies in composition, delivering anywhere from non-existent to supratherapeutic doses. Thyroid supplements should be regulated considering the potential side effects.

Blood Pressure Lowering With Nilvadipine in Patients With Mild-to-Moderate Alzheimer Disease Does Not Increase the Prevalence of Orthostatic Hypotension.

Background Hypertension is common among patients with Alzheimer disease. Because this group has been excluded from hypertension trials, evidence regarding safety of treatment is lacking. This secondary analysis of a randomized controlled trial assessed whether antihypertensive treatment increases the prevalence of orthostatic hypotension (OH) in patients with Alzheimer disease. Methods and Results Four hundred seventy-seven patients with mild-to-moderate Alzheimer disease were randomized to the calcium-channel blocker nilvadipine 8 mg/day or placebo for 78 weeks. Presence of OH (blood pressure drop ≥20/≥10 mm Hg after 1 minute of standing) and OH-related adverse events (dizziness, syncope, falls, and fractures) was determined at 7 follow-up visits. Mean age of the study population was 72.2±8.2 years and mean Mini-Mental State Examination score was 20.4±3.8. Baseline blood pressure was 137.8±14.0/77.0±8.6 mm Hg. Grade I hypertension was present in 53.4% (n=255). After 13 weeks, blood pressure had fallen by -7.8/-3.9 mm Hg for nilvadipine and by -0.4/-0.8 mm Hg for placebo ( P<0.001). Across the 78-week intervention period, there was no difference between groups in the proportion of patients with OH at a study visit (odds ratio [95% CI]=1.1 [0.8-1.5], P=0.62), nor in the proportion of visits where a patient met criteria for OH, corrected for number of visits (7.7±13.8% versus 7.3±11.6%). OH-related adverse events were not more often reported in the intervention group compared with placebo. Results were similar for those with baseline hypertension. Conclusions This study suggests that initiation of a low dose of antihypertensive treatment does not significantly increase the risk of OH in patients with mild-to-moderate Alzheimer disease. Clinical Trial Registration URL: https://www.clinicaltrials.gov . Unique identifier: NCT02017340.

Peripheral edema and headache associated with amlodipine treatment: a meta-analysis of randomized, placebo-controlled trials.

OBJECTIVE: Use of amlodipine for treatment of arterial hypertension and stable coronary artery disease (CAD) is sometimes limited by occurrence of peripheral edema and headache. We aimed to explore the true magnitude of this phenomenon by determining the rate and placebo-adjusted rate of these side effects. METHODS: We performed a meta-analysis by including all randomized, placebo-controlled trials reporting edema and headache with amlodipine in patients with arterial hypertension and CAD. Placebo-adjusted rate (%) was determined as follows: (SE amlodipine % - SE placebo %)/SE amlodipine %. RESULTS: Data from 7226 patients of 22 trials were analyzed. Rate of edema was higher on amlodipine vs. placebo (16.6 vs. 6.2%, risk ratio: 2.9, 95% CI: 2.50-3.36, P < 0.0001). The placebo-adjusted rate was 63%, indicating that 37% of edema cases were unrelated to amlodipine. Treatment with low/medium doses (2.5-5 mg) resulted in lower rates of edema (risk ratio: 2.01, 95% CI: 1.41-2.88, P = 0.0001) vs. high dose (10 mg) (risk ratio: 3.08, 95% CI 2.62-3.60, P < 0.0001, Pforinteraction = 0.03). Incidence of headache was reduced using amlodipine vs. placebo (7.9 vs. 10.9%, risk ratio: 0.77, 95% CI: 0.65-0.90, P = 0.002) and was driven by use of low/medium doses (risk ratio: 0.52, 95% CI: 0.40-0.69, P < 0.00001 vs. risk ratio: 0.92, 95%-CI: 0.74-1.15, P = 0.45, for high doses, Pforinteraction = 0.002). CONCLUSION: Although risks of peripheral edema are three-fold higher on amlodipine, up to one-third of edema cases on amlodipine might not be induced by amlodipine. Headache is reduced on amlodipine treatment, mainly driven by use of this drug at low/medium doses.

Calcium antagonists for acute ischemic stroke.

BACKGROUND: The sudden loss of blood supply in ischemic stroke is associated with an increase of calcium ions within neurons. Inhibiting this increase could protect neurons and might reduce neurological impairment, disability, and handicap after stroke. OBJECTIVES: To assess the effects of calcium antagonists for reducing the risk of death or dependency after acute ischemic stroke. We investigated the influence of different drugs, dosages, routes of administration, time intervals after stroke, and trial design on the outcomes. SEARCH METHODS: The evidence is current to 6 February 2018. We searched the Cochrane Stroke Group Trials Register (6 February 2018), Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 2), MEDLINE Ovid (1950 to 6 February 2018), Embase Ovid (1980 to 6 February 2018), and four Chinese databases (6 February 2018): Chinese Biological Medicine Database (CBM-disc), China National Knowledge Infrastructure (CNKI), Chinese Scientific Periodical Database of VIP information, and Wanfang Data. We also searched the following trials registers: ClinicalTrials.gov, EU Clinical Trials Register, Stroke Trials Registry, ISRCTN registry, WHO International Clinical Trials Registry Platform, and Chinese Clinical Trial Registry, and we contacted trialists and researchers. SELECTION CRITERIA: Randomized controlled trials comparing a calcium antagonist versus control in people with acute ischemic stroke. DATA COLLECTION AND ANALYSIS: Two review authors independently selected trials, extracted data, assessed risk of bias, and applied the GRADE approach to assess the quality of the evidence. We used death or dependency at the end of long-term follow-up (at least three months) in activities of daily living as the primary outcome. We used standard Cochrane methodological procedures. MAIN RESULTS: We included 34 trials involving 7731 participants. All the participants were in the acute stage of ischemic stroke, and their age ranged from 18 to 85 years, with the average age ranging from 52.3 to 74.6 years across different trials. There were more men than women in most trials. Twenty-six trials tested nimodipine, and three trials assessed flunarizine. One trial each used isradipine, nicardipine, PY108-608, fasudil, and lifarizine. More than half of these trials followed participants for at least three months. Calcium antagonists showed no effects on the primary outcome (risk ratio (RR) 1.05; 95% confidence interval (CI) 0.98 to 1.13; 22 trials; 22 studies; 6684 participants; moderate-quality evidence) or on death at the end of follow-up (RR 1.07, 95% CI 0.98 to 1.17; 31 trials; 7483 participants; moderate-quality evidence). Thirteen trials reported adverse events, finding no significant differences between groups. Most trials did not report the allocation process or how they managed missing data, so we considered these at high risk of selection and attrition bias. Most trials reported double-blind methods but did not state who was blinded, and none of the trial protocols were available. AUTHORS' CONCLUSIONS: We found no evidence to support the use of calcium antagonists in people with acute ischemic stroke.