Commentary by Cara Litvin MD, Executive Editor, Clinical Correlations
As winter quickly approaches and we plunge into flu season, it’s fitting that news of a “killer” cold virus broke last week. According to a CDC report, adenovirus serotype 14 (Ad14) is an emerging strain of adenovirus that may cause severe respiratory illness and even death in people of all ages, including healthy young adults. The virus has been linked to 140 cases in 4 states (including NY) between 2006 and 2007. Over a third of these cases resulted in hospitalization, with the virus linked to 10 deaths. Although the infection is uncommon and the CDC has not issued any special precautions, clinicians should be aware of the virus and consider the diagnosis, particularly in younger patients with pneumonia and/or respiratory failure from an unknown source.
Moving from very rare to very common infections, there were over 1 million cases of Chlamydia in the US in 2006, making it the most commonly reported STD. Cases of Chlamydia, gonorrhea, and syphilis are all rising annually. Although more sensitive tests and increased screening efforts may be partially to blame for the increase in reported cases, the incidence of actual infection is also felt to be rising.
And staying on the topic of infectious diseases, a report highlighting the enormous efficacy of vaccines was published in JAMA last week. The report compares historical data with the current state of 12 diseases for which vaccines exist. The use of vaccines for several diseases including diphtheria, tetanus, mumps, and pertussis has resulted in a more than 92% decline in cases, with the elimination of endemic transmission of measles, rubella, and poliovirus. Invasive pneuomococcal cases have declined by 34% and deaths by 25% since 1997-1999 (a useful fact for patients who are reluctant to get the Pneumovax vaccine). As the report reminds us, vaccination is one of the greatest achievements in public health.
Making headlines in the NY Times this week was a report from the American Heart Association conference of a large study that compared death rates between patients who received bare metal stents with those who received drug eluting stents over a 2 year follow up period. Overall mortality of those receiving drug eluting stents was 9.4% compared to 11.9% for those with bare metal stents (P<0.0001) and the rate of revascularization was lower in those with drug eluting stents. This large study eases concerns over the long term safety of drug eluting stents following some recent negative reports over the past year.
Meanwhile, also at the AHA, in a follow up analysis of the Occluded Artery Trial (OAT) examining quality of life outcomes after late stenting (3 to 28 days) of a blocked major coronary artery, PCI, while much more expensive, provided no improvement in quality of life and only a modest benefit in symptoms when compared to patients only medically managed over a two year period after myocardial infarction.
Also reported at the AHA were the results of yet another thiazolidinedione meta-analysis. Actos (pioglitazone) neither increased nor decreased risk of cardiovascular disease or stroke, although there was a significant reduction in some combined cardiovascular outcomes, including MI and unstable angina. The study, although by no means conclusive, provides further evidence that the purported increased cardiovascular risk from Avandia (rosiglitazone) is not a class effect.
Speaking of Avandia, the FDA announced last week that its black box label would be expanded to include a warning reporting that the drug may cause an increased risk of myocardial infarction. Both Actos and Avandia already carry black box warnings for heart failure.