This Week in JAMA FREE

Immunization of infants and children against 2009 influenza A(H1N1) is likely to help control the H1N1 influenza pandemic. However, given the novelty of the virus strain and some uncertainty regarding the immunogenicity of the vaccine in young children, the antigen dose required to elicit an adequate antibody response is not clear. In a randomized, parallel-group study that enrolled 370 infants and children aged 6 months to 9 years, Nolan and colleagues Article assessed the immunogenicity and safety of an inactivated, split-virus 2009 influenza A(H1N1) vaccine that was given as a 2-injection regimen 21 days apart in doses of 15 μg or 30 μg of hemagglutinin antigen. The authors report that a single 15-μg dose of the vaccine was immunogenic, inducing antibody titers of 1:40 or greater in 92.5% (95% confidence interval [CI], 87.6%-95.6%) of infants and children. Among the infants and children randomly assigned to receive the 30-μg dose, 97.7% (95% CI, 94.2%-99.1%) had an antibody titer of 1:40 or greater following the first dose of vaccine. All participants had antibody titers of 1:40 or greater after a second vaccine dose, and vaccine-associated adverse events were mild to moderate in severity—similar to those reported for the seasonal influenza vaccine. In an editorial, Fiore and Neuzil Article discuss the immunogenicity of the influenza A(H1N1) vaccine in infants and children and caution that the findings reported by Nolan and colleagues may not be generalizable to all children.

Antidepressant medications are the current standard of treatment for major depressive disorder, but it is not clear that they have a pharmacological effect greater than that achieved with pill-placebo among patients with less severe depression. In meta-analysis of data from 6 randomized controlled trials of approved antidepressants, Fournier and colleagues assessed the relative benefit of medication vs placebo across a range of initial symptom severity in patients with depression. The authors found that the magnitude of benefit of antidepressant medication compared with pill-placebo increases with the severity of depression symptoms. Among patients with very severe depression, the benefit of medication is substantial, whereas among patients with mild or moderate depression symptoms, the benefit may be minimal or nonexistent.

Mr C is a 43-year-old man who noticed significant nausea and chess tightness without shortness of breath or chest pain during his usual exercise routine of running on a treadmill. His symptoms resolved when he stopped exercising and recurred with resumption of exercise. At his internist's office 4 days later, Mr C was found to have new lateral ST-segment depressions and T-wave inversions on electrocardiogram, so he was transferred to the emergency department for further evaluation. Pinto discusses the evaluation and treatment of patients with acute coronary syndrome/non–ST-segment elevation myocardial infarction, including risk stratification, early invasive management, and medical therapies.

“As [these students’] teacher, respecting the thoughtfulness of their questions, I reply what I hope is an equally thoughtful and honest answer. I don't know.” From “Integration.”

Three national initiatives seek to improve the quality of care provided to patients with stroke.

Extra calories and weight gain

Health risks of carbon capture and storage

Cap and trade legislation for greenhouse gas emissions

Lumbar spinal stenosis

Uniform format for disclosure of competing interests

Join Hussein Hollands, MD, MSc, Wednesday, January 20, from 2 to 3 PM to discuss acute-onset floaters and flashes and risk of retinal detachment. To register, go to http://www.ihi.org/AuthorintheRoom.

Dr DeAngelis summarizes and comments on this week's issue. Go to http://jama.ama-assn.org/misc/audiocommentary.dtl.

For your patients: Information about acute coronary syndromes.