Excess Risk of Cardiac Events Associated with Dabigatran Reply

Compared with controls, dabigatran (Pradaxa) is associated with a higher risk of myocardial infarction (MI) or acute coronary syndrome, according to a new meta-analysis published online in Archives of Internal Medicine.

Ken Uchino and Adrian Hernandez analyzed data from seven clinical trials comparing dabigatran with warfarin, enoxaparin, or placebo in 30,514 patients. The rate of MI or ACS was significantly higher in the dabigatran groups than in the control groups:

Statins Elevate Risk of Diabetes in Postmenopausal Women Reply

Statins increase the risk of developing diabetes in postmenopausal women, according to a new study published in Archives of Internal Medicine. The study provides more evidence and details about the previously reported link between statins and the development of diabetes.

Using data from more than 153,000 postmenopausal women who were participating in the Women’s Health Initiative (WHI) and who did not have diabetes mellitus (DM) at baseline, and containing more than 1 million person-years of follow-up, the investigators found a significant increase in the risk of diabetes in women taking statins at baseline:

Researchers Report a New Placebo Effect: Manipulating Clinical Trials 2

Two Danish diabetes researchers claim that the pharmaceutical industry may be manipulating independent clinical research by controlling access to placebo drugs or devices. In a letter published in the Lancet, Mikkel Christensen and Filip K Knop write that “this could be a major way for the pharmaceutical industry to control scientific information about their drugs.”

They cite an example in which researchers sought to obtain a placebo diabetes medication in a specialized injection pen “for an independently financed trial to investigate the effect of a marketed drug.” Here’s what happened:

Before considering delivery of placebo, the company asked for a full protocol to be scrutinised by an opaque system of evaluation committees. After more than 6 months, the company finally agreed to supply placebo devices provided that the protocol was changed according to their suggestions. The researchers were also obliged to allow the company access to the resulting trial report for 4 weeks before submission for publication.

Diets Differ in Effect on Weight Gain and Fat and Lean Mass Reply

A new study published in JAMA demonstrates the various effects of overeating of three diets that differed mainly in protein composition.

George Bray and colleagues randomized 25 healthy volunteers to participate in an inpatient study to consume low, normal, or high protein diets which provided 40% more calories than required to maintain their normal weight. After 8 weeks there was less weight gain in the low protein group than in the other groups (p=.002).

Weight gain:

• low protein group: 3.16 kg
• normal protein group: 6.05 kg
• high protein diet group: 6.51 kg

However, there was no difference between the groups in the increase in body fat, and the low protein diet caused no increase in energy expenditure or lean body mass. By contrast, energy expenditure and lean body mass increased with the normal and high protein diets.

High STEMI Readmission Rate in US Linked to Shorter Hospital Stays Reply

STEMI (ST-segment elevation myocardial infarction) patients in the US are more likely to be readmitted to the hospital within 30 days compared to patients outside the US, but this difference loses significance when length of stay (LOS) is taken into account, according to a new study published in JAMA. 

Robb Cociol and colleagues analyzed data from 5,745 STEMI patients enrolled in the Assessment of Pexelizumab in Acute Myocardial Infarction trial and found that US patients had a 68% increase in the risk of readmission compared to patients outside the US.

Missing Data: The Elephant That’s Not in the Room (Guest Post) 2

Editor’s Note: The following guest post by Harlan Krumholz is reprinted with permission from CardioExchange, the cardiology social media website published by the New England Journal of Medicine.

Missing Data: The Elephant That’s Not in the Room

by Harlan M. Krumholz, MD, SM

There is a problem so grave that it threatens the very validity of what we learn from the medical literature. Bad data? Not exactly. Actually, it’s missing data — information, relevant to the risks and benefits of treatments, that is simply not published. In some cases, these data would make a critical difference in the inferences that readers draw from the literature. The absence of the data renders meta-analyses, systematic reviews, and book chapters suspect. Conclusions are made on the basis of incomplete science. In short, publication bias and selective publication are impugning the validity of what we can learn from a PubMed search or even the most careful review of published studies.

This matter demands our immediate attention and speaks to the need to rethink the configuration of clinical medical science. It may be time to adopt strategies to ensure that all relevant studies, results, and supporting documentation are made publicly available. “Out of sight, out of mind” is a dangerous reality in science and medicine. It’s time for a change — and it starts with the recognition that we have a problem.

I urge you to read BMJ this week to explore the evidence of this problem. In full disclosure, the studies include one by me (with others, led by Joe Ross) showing that more than half of trials sponsored by the NIH go unpublished even 30 months after completion. The other articles reveal troubling information, including about how missing data can affect the results of meta-analyses — and how many investigators are ignoring the requirements for mandatory reporting of trial results, raising the question of what “mandatory” actually means.

Bariatric Surgery Cuts Cardiovascular Deaths and Events Reply

Bariatric surgery results in significant reductions in cardiovascular deaths and events, according to a new study from Sweden published in JAMA. But one expert cautions that the results do not mean that obese patients without other weight-related complications should undergo surgery.

Analyzing data from more than 4,000 obese patients enrolled in the ongoing Swedish Obese Subjects (SOS) study, Lars Sjöström and colleagues found that bariatric surgery was associated with a reduction in cardiovascular events and deaths after a mean followup of 14.7 years. (The investigators had previously reported a reduction in total mortality in the treatment group.)

Measuring In-Hospital Mortality Favors Hospitals with Short Stays Reply

As a measure of performance and quality, in-hospital mortality systematically favors hospitals with shorter length of stay (LOS) times, according to a new study published in Annals of Internal Medicine. The finding may have important implications for quality improvement initiatives that use mortality as a performance measure.

Elizabeth Drye and colleagues analyzed Medicare data from 3.5 million hospital admissions for acute MI, heart failure, and pneumonia. They observed  wide variations in the LOS for each condition and large differences between the in-hospital and 30-day mortality rates. Performance ratings were different for a substantial number of hospitals based on the mortality assessment used.

Acute MI:

• Mean LOS varied from 2.3 to 13.7 days
• In-hospital mortality and 30 day mortality: 10.8% and 16.1%
• 8.2% of hospitals had a change in performance classification based on type of mortality assessment