Saturday, January 31, 2009

Giant Osteoclast Formation and Long-Term Oral Bisphosphonate Therapy

Robert S. Weinstein, M.D., Paula K. Roberson, Ph.D., and Stavros C. Manolagas, M.D., Ph.D.

ABSTRACT

Background Bisphosphonates decrease bone resorption and are commonly used to treat or prevent osteoporosis. However, the effect of bisphosphonates on their target cells remains enigmatic, since in patients benefiting from therapy, little change, if any, has been observed in the number of osteoclasts, which are the cells responsible for bone resorption.

Methods We examined 51 bone-biopsy specimens obtained after a 3-year, double-blind, randomized, placebo-controlled, dose-ranging trial of oral alendronate to prevent bone resorption among healthy postmenopausal women 40 through 59 years of age. The patients were assigned to one of five groups: those receiving placebo for 3 years; alendronate at a dose of 1, 5, or 10 mg per day for 3 years; or alendronate at a dose of 20 mg per day for 2 years, followed by placebo for 1 year. Formalin-fixed, undecalcified planar sections were assessed by bone histomorphometric methods.

Results The number of osteoclasts was increased by a factor of 2.6 in patients receiving 10 mg of alendronate per day for 3 years as compared with the placebo group (P<0.01).> the number of osteoclasts increased as the cumulative dose of the drug increased (r=0.50, P<0.001).> of these osteoclasts were giant cells with pyknotic nuclei that were adjacent to superficial resorption cavities. Furthermore, giant, hypernucleated, detached osteoclasts with 20 to 40 nuclei were found after alendronate treatment had been discontinued for 1 year. Of these large cells, 20 to 37% were apoptotic, according to both their morphologic features and positive findings from in situ end labeling.

Conclusions Long-term alendronate treatment is associated with an increase in the number of osteoclasts, which include distinctive giant, hypernucleated, detached osteoclasts that are undergoing protracted apoptosis.

Aspirin and Extended-Release Dipyridamole versus Clopidogrel for Recurrent Stroke

Ralph L. Sacco, M.D., Hans-Christoph Diener, M.D., Ph.D., Salim Yusuf, M.B., B.S., D.Phil., Daniel Cotton, M.S., Stephanie Ôunpuu, Ph.D., William A. Lawton, B.A., Yuko Palesch, Ph.D., Reneé H. Martin, Ph.D., Gregory W. Albers, M.D., Philip Bath, F.R.C.P., Natan Bornstein, M.D., Bernard P.L. Chan, M.D., Sien-Tsong Chen, M.D., Luis Cunha, M.D., Ph.D., Björn Dahlöf, M.D., Ph.D., Jacques De Keyser, M.D., Ph.D., Geoffrey A. Donnan, M.D., Conrado Estol, M.D., Ph.D., Philip Gorelick, M.D., Vivian Gu, M.D., Karin Hermansson, D.M.Sc., Lutz Hilbrich, M.D., Markku Kaste, M.D., Ph.D., Chuanzhen Lu, M.D., Thomas Machnig, M.D., Prem Pais, M.D., Robin Roberts, M.Tech., Veronika Skvortsova, M.D., Philip Teal, M.D., Danilo Toni, M.D., Cam VanderMaelen, Ph.D., Thor Voigt, M.D., Michael Weber, M.D., Byung-Woo Yoon, M.D., Ph.D., for the PRoFESS Study Group

ABSTRACT

Background Recurrent stroke is a frequent, disabling event after ischemic stroke. This study compared the efficacy and safety of two antiplatelet regimens — aspirin plus extended-release dipyridamole (ASA–ERDP) versus clopidogrel.

Methods In this double-blind, 2-by-2 factorial trial, we randomly assigned patients to receive 25 mg of aspirin plus 200 mg of extended-release dipyridamole twice daily or to receive 75 mg of clopidogrel daily. The primary outcome was first recurrence of stroke. The secondary outcome was a composite of stroke, myocardial infarction, or death from vascular causes. Sequential statistical testing of noninferiority (margin of 1.075), followed by superiority testing, was planned.

Results A total of 20,332 patients were followed for a mean of 2.5 years. Recurrent stroke occurred in 916 patients (9.0%) receiving ASA–ERDP and in 898 patients (8.8%) receiving clopidogrel (hazard ratio, 1.01; 95% confidence interval [CI], 0.92 to 1.11). The secondary outcome occurred in 1333 patients (13.1%) in each group (hazard ratio for ASA–ERDP, 0.99; 95% CI, 0.92 to 1.07). There were more major hemorrhagic events among ASA–ERDP recipients (419 [4.1%]) than among clopidogrel recipients (365 [3.6%]) (hazard ratio, 1.15; 95% CI, 1.00 to 1.32), including intracranial hemorrhage (hazard ratio, 1.42; 95% CI, 1.11 to 1.83). The net risk of recurrent stroke or major hemorrhagic event was similar in the two groups (1194 ASA–ERDP recipients [11.7%], vs. 1156 clopidogrel recipients [11.4%]; hazard ratio, 1.03; 95% CI, 0.95 to 1.11).

Conclusions The trial did not meet the predefined criteria for noninferiority but showed similar rates of recurrent stroke with ASA–ERDP and with clopidogrel. There is no evidence that either of the two treatments was superior to the other in the prevention of recurrent stroke. (ClinicalTrials.gov number, NCT00153062 [ClinicalTrials.gov] .)

Friday, January 30, 2009

Telmisartan to Prevent Recurrent Stroke and Cardiovascular Events

Salim Yusuf, M.B., B.S., D.Phil., Hans-Christoph Diener, M.D., Ph.D., Ralph L. Sacco, M.D., Daniel Cotton, M.S., Stephanie Ôunpuu, Ph.D., William A. Lawton, B.A., Yuko Palesch, Ph.D., Reneé H. Martin, Ph.D., Gregory W. Albers, M.D., Philip Bath, F.R.C.P., Natan Bornstein, M.D., Bernard P.L. Chan, M.D., Sien-Tsong Chen, M.D., Luis Cunha, M.D., Ph.D., Björn Dahlöf, M.D., Ph.D., Jacques De Keyser, M.D., Ph.D., Geoffrey A. Donnan, M.D., Conrado Estol, M.D., Ph.D., Philip Gorelick, M.D., Vivian Gu, M.D., Karin Hermansson, D.M.Sc., Lutz Hilbrich, M.D., Markku Kaste, M.D., Ph.D., Chuanzhen Lu, M.D., Thomas Machnig, M.D., Prem Pais, M.D., Robin Roberts, M.Tech., Veronika Skvortsova, M.D., Philip Teal, M.D., Danilo Toni, M.D., Cam VanderMaelen, Ph.D., Thor Voigt, M.D., Michael Weber, M.D., Byung-Woo Yoon, M.D., Ph.D., for the PRoFESS Study Group

ABSTRACT

Background Prolonged lowering of blood pressure after a stroke reduces the risk of recurrent stroke. In addition, inhibition of the renin–angiotensin system in high-risk patients reduces the rate of subsequent cardiovascular events, including stroke. However, the effect of lowering of blood pressure with a renin–angiotensin system inhibitor soon after a stroke has not been clearly established. We evaluated the effects of therapy with an angiotensin-receptor blocker, telmisartan, initiated early after a stroke.

Methods In a multicenter trial involving 20,332 patients who recently had an ischemic stroke, we randomly assigned 10,146 to receive telmisartan (80 mg daily) and 10,186 to receive placebo. The primary outcome was recurrent stroke. Secondary outcomes were major cardiovascular events (death from cardiovascular causes, recurrent stroke, myocardial infarction, or new or worsening heart failure) and new-onset diabetes.

Results The median interval from stroke to randomization was 15 days. During a mean follow-up of 2.5 years, the mean blood pressure was 3.8/2.0 mm Hg lower in the telmisartan group than in the placebo group. A total of 880 patients (8.7%) in the telmisartan group and 934 patients (9.2%) in the placebo group had a subsequent stroke (hazard ratio in the telmisartan group, 0.95; 95% confidence interval [CI], 0.86 to 1.04; P=0.23). Major cardiovascular events occurred in 1367 patients (13.5%) in the telmisartan group and 1463 patients (14.4%) in the placebo group (hazard ratio, 0.94; 95% CI, 0.87 to 1.01; P=0.11). New-onset diabetes occurred in 1.7% of the telmisartan group and 2.1% of the placebo group (hazard ratio, 0.82; 95% CI, 0.65 to 1.04; P=0.10).

Conclusions Therapy with telmisartan initiated soon after an ischemic stroke and continued for 2.5 years did not significantly lower the rate of recurrent stroke, major cardiovascular events, or diabetes. (ClinicalTrials.gov number, NCT00153062 [ClinicalTrials.gov] .)

Thrombolysis with Alteplase 3 to 4.5 Hours after Acute Ischemic Stroke

Werner Hacke, M.D., Markku Kaste, M.D., Erich Bluhmki, Ph.D., Miroslav Brozman, M.D., Antoni Dávalos, M.D., Donata Guidetti, M.D., Vincent Larrue, M.D., Kennedy R. Lees, M.D., Zakaria Medeghri, M.D., Thomas Machnig, M.D., Dietmar Schneider, M.D., Rüdiger von Kummer, M.D., Nils Wahlgren, M.D., Danilo Toni, M.D., for the ECASS Investigators

ABSTRACT

Background Intravenous thrombolysis with alteplase is the only approved treatment for acute ischemic stroke, but its efficacy and safety when administered more than 3 hours after the onset of symptoms have not been established. We tested the efficacy and safety of alteplase administered between 3 and 4.5 hours after the onset of a stroke.

Methods After exclusion of patients with a brain hemorrhage or major infarction, as detected on a computed tomographic scan, we randomly assigned patients with acute ischemic stroke in a 1:1 double-blind fashion to receive treatment with intravenous alteplase (0.9 mg per kilogram of body weight) or placebo. The primary end point was disability at 90 days, dichotomized as a favorable outcome (a score of 0 or 1 on the modified Rankin scale, which has a range of 0 to 6, with 0 indicating no symptoms at all and 6 indicating death) or an unfavorable outcome (a score of 2 to 6 on the modified Rankin scale). The secondary end point was a global outcome analysis of four neurologic and disability scores combined. Safety end points included death, symptomatic intracranial hemorrhage, and other serious adverse events.

Results We enrolled a total of 821 patients in the study and randomly assigned 418 to the alteplase group and 403 to the placebo group. The median time for the administration of alteplase was 3 hours 59 minutes. More patients had a favorable outcome with alteplase than with placebo (52.4% vs. 45.2%; odds ratio, 1.34; 95% confidence interval [CI], 1.02 to 1.76; P=0.04). In the global analysis, the outcome was also improved with alteplase as compared with placebo (odds ratio, 1.28; 95% CI, 1.00 to 1.65; P<0.05).> higher with alteplase than with placebo (for any intracranial hemorrhage, 27.0% vs. 17.6%; P=0.001; for symptomatic intracranial hemorrhage, 2.4% vs. 0.2%; P=0.008). Mortality did not differ significantly between the alteplase and placebo groups (7.7% and 8.4%, respectively; P=0.68). There was no significant difference in the rate of other serious adverse events.

Conclusions As compared with placebo, intravenous alteplase administered between 3 and 4.5 hours after the onset of symptoms significantly improved clinical outcomes in patients with acute ischemic stroke; alteplase was more frequently associated with symptomatic intracranial hemorrhage. (ClinicalTrials.gov number, NCT00153036 [ClinicalTrials.gov] .)

Rosuvastatin to Prevent Vascular Events in Men and Women with Elevated C-Reactive Protein

Paul M Ridker, M.D., Eleanor Danielson, M.I.A., Francisco A.H. Fonseca, M.D., Jacques Genest, M.D., Antonio M. Gotto, Jr., M.D., John J.P. Kastelein, M.D., Wolfgang Koenig, M.D., Peter Libby, M.D., Alberto J. Lorenzatti, M.D., Jean G. MacFadyen, B.A., Børge G. Nordestgaard, M.D., James Shepherd, M.D., James T. Willerson, M.D., Robert J. Glynn, Sc.D., for the JUPITER Study Group

ABSTRACT

Background Increased levels of the inflammatory biomarker high-sensitivity C-reactive protein predict cardiovascular events. Since statins lower levels of high-sensitivity C-reactive protein as well as cholesterol, we hypothesized that people with elevated high-sensitivity C-reactive protein levels but without hyperlipidemia might benefit from statin treatment.

Methods We randomly assigned 17,802 apparently healthy men and women with low-density lipoprotein (LDL) cholesterol levels of less than 130 mg per deciliter (3.4 mmol per liter) and high-sensitivity C-reactive protein levels of 2.0 mg per liter or higher to rosuvastatin, 20 mg daily, or placebo and followed them for the occurrence of the combined primary end point of myocardial infarction, stroke, arterial revascularization, hospitalization for unstable angina, or death from cardiovascular causes.

Results The trial was stopped after a median follow-up of 1.9 years (maximum, 5.0). Rosuvastatin reduced LDL cholesterol levels by 50% and high-sensitivity C-reactive protein levels by 37%. The rates of the primary end point were 0.77 and 1.36 per 100 person-years of follow-up in the rosuvastatin and placebo groups, respectively (hazard ratio for rosuvastatin, 0.56; 95% confidence interval [CI], 0.46 to 0.69; P<0.00001),> rates of 0.17 and 0.37 for myocardial infarction (hazard ratio, 0.46; 95% CI, 0.30 to 0.70; P=0.0002), 0.18 and 0.34 for stroke (hazard ratio, 0.52; 95% CI, 0.34 to 0.79; P=0.002), 0.41 and 0.77 for revascularization or unstable angina (hazard ratio, 0.53; 95% CI, 0.40 to 0.70; P<0.00001),> the combined end point of myocardial infarction, stroke, or death from cardiovascular causes (hazard ratio, 0.53; 95% CI, 0.40 to 0.69; P<0.00001),> any cause (hazard ratio, 0.80; 95% CI, 0.67 to 0.97; P=0.02). Consistent effects were observed in all subgroups evaluated. The rosuvastatin group did not have a significant increase in myopathy or cancer but did have a higher incidence of physician-reported diabetes.

Conclusions In this trial of apparently healthy persons without hyperlipidemia but with elevated high-sensitivity C-reactive protein levels, rosuvastatin significantly reduced the incidence of major cardiovascular events. (ClinicalTrials.gov number, NCT00239681 [ClinicalTrials.gov] .)

Valvular Heart Disease and the Use of Dopamine Agonists for Parkinson's Disease

Renzo Zanettini, M.D., Angelo Antonini, M.D., Gemma Gatto, M.D., Rosa Gentile, M.D., Silvana Tesei, M.D., and Gianni Pezzoli, M.D.

ABSTRACT

Background Ergot-derived dopamine receptor agonists, often used in the treatment of Parkinson's disease, have been associated with an increased risk of valvular heart disease.

Methods We performed an echocardiographic prevalence study in 155 patients taking dopamine agonists for Parkinson's disease (pergolide, 64 patients; cabergoline, 49; and non–ergot-derived dopamine agonists, 42) and 90 control subjects. Valve regurgitation was assessed according to American Society of Echocardiography recommendations. The mitral-valve tenting area was also measured and used as a quantitative index for leaflet stiffening and apical displacement of leaflet coaptation.

Results Clinically important regurgitation (moderate to severe, grade 3 to 4) in any valve was found with significantly greater frequency in patients taking pergolide (23.4%) or cabergoline (28.6%) but not in patients taking non–ergot-derived dopamine agonists (0%), as compared with control subjects (5.6%). The relative risk for moderate or severe valve regurgitation in the pergolide group was 6.3 for mitral regurgitation (P=0.008), 4.2 for aortic regurgitation (P=0.01), and 5.6 for tricuspid regurgitation (P=0.16); corresponding relative risks in the cabergoline group were 4.6 (P=0.09), 7.3 (P<0.001),> (P=0.12). The mean mitral tenting area was significantly greater in ergot-treated patients and showed a linear relationship with the severity of mitral regurgitation. Patients treated with ergot derivatives who had grade 3 to 4 regurgitation of any valve had received a significantly higher mean cumulative dose of pergolide or cabergoline than had patients with lower grades.

Conclusions The frequency of clinically important valve regurgitation was significantly increased in patients taking pergolide or cabergoline, but not in patients taking non–ergot-derived dopamine agonists, as compared with control subjects. These findings should be considered in evaluating the risk–benefit ratio of treatment with ergot derivatives.

Dopamine Agonists and the Risk of Cardiac-Valve Regurgitation

René Schade, M.D., Frank Andersohn, M.D., Samy Suissa, Ph.D., Wilhelm Haverkamp, M.D., Ph.D., and Edeltraut Garbe, M.D., Ph.D

ABSTRACT

Background Case reports and echocardiographic studies suggest that the ergot-derived dopamine agonists pergolide and cabergoline, used in the treatment of Parkinson's disease and the restless legs syndrome, may increase the risk of cardiac-valve regurgitation.

Methods We used data from the United Kingdom General Practice Research Database to identify a population-based cohort comprising 11,417 subjects 40 to 80 years of age who were prescribed antiparkinsonian drugs between 1988 and 2005. We conducted a nested case–control analysis within this cohort in which each patient with newly diagnosed cardiac-valve regurgitation was matched with up to 25 control subjects from the cohort, according to age, sex, and year of entry into the cohort. Incidence-rate ratios for cardiac-valve regurgitation with the use of different dopamine agonists were estimated by conditional logistic-regression analysis.

Results Of 31 case patients with newly diagnosed cardiac-valve regurgitation, 6 were currently exposed to pergolide, 6 were currently exposed to cabergoline, and 19 had not been exposed to any dopamine agonist within the previous year. The rate of cardiac-valve regurgitation was increased with current use of pergolide (incidence-rate ratio, 7.1; 95% confidence interval [CI], 2.3 to 22.3) and cabergoline (incidence-rate ratio, 4.9; 95% CI, 1.5 to 15.6), but not with current use of other dopamine agonists.

Conclusions In this study, use of the dopamine agonists pergolide and cabergoline was associated with an increased risk of newly diagnosed cardiac-valve regurgitation.