Reperfusion therapy for acute myocardial infarction: observations from the National Registry of Myocardial Infarction 2

The National Registry of Myocardial Infarction 2 (NRMI-2) provides a unique opportunity to evaluate the practice patterns among participating cardiology and emergency medicine departments involved in the care of patients with acute myocardial infarction. The data from NRMI-2 suggest that almost 1/3 of all non-transfer-in and non-transfer-out patients are eligible for reperfusion therapy. Furthermore, of those patients who are clearly eligible for reperfusion therapy, 24% are not given this proven therapy. Specifically, women, the elderly, patients without chest pain on presentation, and those patients at highest risk for in-hospital mortality were least likely to be treated with reperfusion therapy. The reason for underuse of reperfusion therapy may in part reflect a concern for adverse bleeding events associated with the use of thrombolytic therapy. The data from NRMI-2 also suggest that patients with contraindications to thrombolysis may be very appropriate for primary angioplasty. Realizing the full potential benefits of reperfusion therapy in terms of reduced cardiovascular morbidity and mortality will require that clinical practice patterns be aligned more closely with the recommended national guidelines, which are based on extensive clinical trial data that show the benefit of reperfusion therapy in a wide range of patients with acute myocardial infarction. By using observational databases, such as the NRMI-2, which describe how clinical care is administered in nonclinical trial settings, we can continually monitor our progress and initiate changes to ensure that patients are given access to the many therapies that have been shown to improve their quality of life and survival

Long-term outcomes of ranibizumab therapy for diabetic macular edema: the 36-month results from two phase III trials: RISE and RIDE.

PURPOSE: To report 36-month outcomes of RIDE (NCT00473382) and RISE (NCT00473330), trials of ranibizumab in diabetic macular edema (DME). DESIGN: Phase III, randomized, multicenter, double-masked, 3-year trials, sham injection-controlled for 2 years. PARTICIPANTS: Adults with DME (n=759), baseline best-corrected visual acuity (BCVA) 20/40 to 20/320 Snellen equivalent, and central foveal thickness (CFT) ≥ 275 μm on optical coherence tomography. METHODS: Patients were randomized equally (1 eye per patient) to monthly 0.5 mg or 0.3 mg ranibizumab or sham injection. In the third year, sham patients, while still masked, were eligible to cross over to monthly 0.5 mg ranibizumab. Macular laser was available to all patients starting at month 3; panretinal laser was available as necessary. MAIN OUTCOME MEASURES: The proportion of patients gaining ≥15 Early Treatment Diabetic Retinopathy Study letters in BCVA from baseline at month 24. RESULTS: Visual acuity (VA) outcomes seen at month 24 in ranibizumab groups were consistent through month 36; the proportions of patients who gained ≥15 letters from baseline at month 36 in the sham/0.5 mg, 0.3 mg, and 0.5 mg ranibizumab groups were 19.2%, 36.8%, and 40.2%, respectively, in RIDE and 22.0%, 51.2%, and 41.6%, respectively, in RISE. In the ranibizumab arms, reductions in CFT seen at 24 months were, on average, sustained through month 36. After crossover to 1 year of treatment with ranibizumab, average VA gains in the sham/0.5 mg group were lower compared with gains seen in the ranibizumab patients after 1 year of treatment (2.8 vs. 10.6 and 11.1 letters). Per-injection rates of endophthalmitis remained low over time (∼0.06% per injection). The incidence of serious adverse events potentially related to systemic vascular endothelial growth factor inhibition was 19.7% in patients who received 0.5 mg ranibizumab compared with 16.8% in the 0.3 mg group. CONCLUSIONS: The strong VA gains and improvement in retinal anatomy achieved with ranibizumab at month 24 were sustained through month 36. Delayed treatment in patients receiving sham treatment did not seem to result in the same extent of VA improvement observed in patients originally randomized to ranibizumab. Ocular and systemic safety was generally consistent with the results seen at month 24. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references

Species Differentiation on a Dynamic Landscape: Shifts in Metapopulation Genetic Structure Using the Chronology of the Hawaiian Archipelago

Species formation during adaptive radiation often occurs in the context of a changing environment. The establishment and arrangement of populations, in space and time, sets up ecological and genetic processes that dictate the rate and pattern of differentiation. Here, we focus on how a dynamic habitat can affect genetic structure, and ultimately, differentiation among populations. We make use of the chronology and geographical history provided by the Hawaiian archipelago to examine the initial stages of population establishment and genetic divergence. We use data from a set of 6 spider lineages that differ in habitat affinities, some preferring low elevation habitats with a longer history of connection, others being more specialized for high elevation and/or wet forest, some with more general habitat affinities. We show that habitat preferences associated with lineages are important in ecological and genetic structuring. Lineages that have more restricted habitat preferences are subject to repeated episodes of isolation and fragmentation as a result of lava flows and vegetation succession. The initial dynamic set up by the landscape translates over time into discrete lineages. Further work is needed to understand how genetic changes interact with a changing set of ecological interactions amongst a shifting mosaic of landscapes to achieve species formation

Intracranial hemorrhage rates and effect of immediate beta-blocker use in patients with acute myocardial infarction treated with tissue plasminogen activator. Participants in the National Registry of Myocardial Infarction-2.

In acute myocardial infarction (AMI), immediate beta-blocker therapy reduces the incidence of reinfarction and recurrent chest pain in patients receiving tissue plasminogen activator (t-PA). Data from the Thrombolysis in Myocardial Infarction (TIMI)-2 trial also raises the possibility that such therapy may reduce the rate of intracranial hemorrhage (ICH). We reviewed data obtained from 60,329 patients treated with t-PA who were enrolled in the National Registry of Myocardial Infarction 2. Of the 60,329 in the study cohort, 23,749 patients (39.4%) were treated with immediate beta-blocker therapy and 542 patients (0.9%) developed an ICH. In a multivariate model that included all covariates known to be associated with the development of ICH, immediate beta-blocker therapy was associated with a 31% reduction in the ICH rate (odds ratio 0.69, 95% confidence intervals 0.57 to 0.84). Thus, in the present study, the use of immediate beta-blocker therapy in patients with AMI treated with t-PA was associated with a significant reduction in ICH. This finding supports the observations made in the TIMI 2 trial and serves to reinforce the recommendations made by the American College of Cardiology/American Heart Association task force that immediate beta-blocker therapy should be administered to all patients with AMI who do not have contraindications to this therapy

Risk for intracranial hemorrhage after tissue plasminogen activator treatment for acute myocardial infarction. Participants in the National Registry of Myocardial Infarction 2

BACKGROUND: The efficacy of thrombolytic therapy in reducing mortality from acute myocardial infarction has been unequivocally shown. However, thrombolysis is related to bleeding complications, including intracranial hemorrhage. OBJECTIVE: To determine the frequency of and risk factors for intracranial hemorrhage after recombinant tissue-type plasminogen activator (tPA) given for acute myocardial infarction in patients receiving usual care. DESIGN: Large national registry of patients who have had acute myocardial infarction. SETTING: 1484 U.S. hospitals. PATIENTS: 71073 patients who had had acute myocardial infarction from 1 June 1994 to 30 September 1996, received tPA as the initial reperfusion strategy, and did not receive a second dose of any thrombolytic agent. MEASUREMENT: Intracranial hemorrhage confirmed by computed tomography or magnetic resonance imaging. RESULTS: 673 patients (0.95%) were reported to have had intracranial hemorrhage during hospitalization for acute myocardial infarction; 625 patients (0.88%) had the event confirmed by computed tomography or magnetic resonance imaging. Of the 625 patients with confirmed intracranial hemorrhage, 331 (53%) died during hospitalization. An additional 158 patients (25.3%) who survived to hospital discharge had residual neurologic deficit. In multivariable models for the main effects of candidate risk factors, older age, female sex, black ethnicity, systolic blood pressure of 140 mm Hg or more, diastolic blood pressure of 100 mm Hg or more, history of stroke, tPA dose more than 1.5 mg/kg, and lower body weight were significantly associated with intracranial hemorrhage. CONCLUSIONS: Intracranial hemorrhage is a rare but serious complication of tPA in patients with acute myocardial infarction. Appropriate drug dosing may reduce the risk for this complication. Other therapies, such as primary coronary angioplasty, may be preferable in patients with acute myocardial infarction who have a history of stroke

The Role of Childhood Asthma in Obesity Development

RationaleAsthma and obesity often co-occur. It has been hypothesized that asthma may contribute to childhood obesity onset.ObjectivesTo determine if childhood asthma is associated with incident obesity and examine the role of asthma medication in this association.MethodsWe studied 8,716 children between ages 6 and 18.5 years who were nonobese at study entry participating in 18 US cohorts of the Environmental influences on Child Health Outcomes program (among 7,299 children with complete covariate data mean [SD] study entry age = 7.2 [1.6] years and follow up = 5.3 [3.1] years).Measurements and main resultsWe defined asthma based on caregiver report of provider diagnosis. Incident obesity was defined as the first documented body mass index ≥95th percentile for age and sex following asthma status ascertainment. Over the study period, 26% of children had an asthma diagnosis and 11% developed obesity. Cox proportional hazards models with sex-specific baseline hazards were fitted to assess the association of asthma diagnosis with obesity incidence. Children with asthma had a 23% (95% confidence intervals [CI] = 4, 44) higher risk for subsequently developing obesity compared with those without asthma. A novel mediation analysis was also conducted to decompose the total asthma effect on obesity into pathways mediated and not mediated by asthma medication use. Use of asthma medication attenuated the total estimated effect of asthma on obesity by 64% (excess hazard ratios = 0.64; 95% CI = -1.05, -0.23).ConclusionsThis nationwide study supports the hypothesis that childhood asthma is associated with later risk of obesity. Asthma medication may reduce this association and merits further investigation as a potential strategy for obesity prevention among children with asthma