Objective To determine rates of publication and reporting of results within two years for all completed clinical trials registered in ClinicalTrials.gov across leading academic medical centers in the United States. Design Cross sectional analysis. Setting Academic medical centers in the United States. Participants Academic medical centers with 40 or more completed interventional trials registered on ClinicalTrials.gov. Methods Using the Aggregate Analysis of ClinicalTrials.gov database and manual review, we identified all interventional clinical trials registered on ClinicalTrials.gov with a primary completion date between October 2007 and September 2010 and with a lead investigator affiliated with an academic medical center. Main outcome measures The proportion of trials that disseminated results, defined as publication or reporting of results on ClinicalTrials.gov, overall and within 24 months of study completion. Results We identified 4347 interventional clinical trials across 51 academic medical centers. Among the trials, 1005 (23%) enrolled more than 100 patients, 1216 (28%) were double blind, and 2169 (50%) were phase II through IV. Overall, academic medical centers disseminated results for 2892 (66%) trials, with 1560 (35.9%) achieving this within 24 months of study completion. The proportion of clinical trials with results disseminated within 24 months of study completion ranged from 16.2% (6/37) to 55.3% (57/103) across academic medical centers. The proportion of clinical trials published within 24 months of study completion ranged from 10.8% (4/37) to 40.3% (31/77) across academic medical centers, whereas results reporting on ClinicalTrials.gov ranged from 1.6% (2/122) to 40.7% (72/177). Conclusions Despite the ethical mandate and expressed values and mission of academic institutions, there is poor performance and noticeable variation in the dissemination of clinical trial results across leading academic medical centers.
9 June 2009 in Proceedings of the National Academy of Sciences
Calorie restriction (CR) improves health and extends life span in a variety of species. Despite many downstream molecules and physiological systems having been identified as being regulated by CR, the mechanism by which CR extends life span remains unclear. The Drosophila gene Indy (for I'm not dead yet), involved in the transport and storage of Krebs cycle intermediates in tissues important in fly metabolism, was proposed to regulate life span via an effect on metabolism that could overlap with CR. In this study, we report that CR down regulates Indy mRNA expression, and that CR and the level of Indy expression interact to affect longevity. Optimal life span extension is seen when Indy expression is decreased between 25 and 75% of normal. Indy long-lived flies show several phenotypes that are shared by long-lived CR flies, including decreased insulin-like signaling, lipid storage, weight gain, and resistance to starvation as well as an increase in spontaneous physical activity. We conclude that Indy and CR interact to affect longevity and that a decrease in Indy may induce a CR-like status that confers life span extension.
Several models of arteriovenous fistula (AVF) have excellent patency and help in understanding the mechanisms of venous adaptation to the arterial environment. However, these models fail to exhibit either maturation failure or fail to develop stenoses, both of which are critical modes of AVF failure in human patients. We used high-resolution Doppler ultrasound to serially follow mice with AVFs created by direct 25-gauge needle puncture. By day 21, 75% of AVFs dilate, thicken, and increase flow, i.e., mature, and 25% fail due to immediate thrombosis or maturation failure. Mature AVF thicken due to increased amounts of smooth muscle cells. By day 42, 67% of mature AVFs remain patent, but 33% of AVFs fail due to perianastomotic thickening. These results show that the mouse aortocaval model has an easily detectable maturation phase in the first 21 days followed by a potential failure phase in the subsequent 21 days. This model is the first animal model of AVF to show a course that recapitulates aspects of human AVF maturation.
Background: Venoarterial extracorporeal membrane oxygenation (VA‐ECMO) is increasingly used for patients with cardiogenic shock. Although Impella or intra‐aortic balloon pump (IABP) is frequently used for left ventricular unloading (LVU) during VA‐ECMO treatment, there are limited data on comparative outcomes. We compared outcomes of Impella and IABP for LVU during VA‐ECMO. Methods and Results: Using the Nationwide Readmissions Database between 2016 and 2020, we analyzed outcomes in 3 groups of patients with cardiogenic shock requiring VA‐ECMO based on LVU strategies: extracorporeal membrane oxygenation (ECMO) only, ECMO with IABP, and ECMO with Impella. Of 15 980 patients on VA‐ECMO, IABP and Impella were used in 19.4% and 16.4%, respectively. The proportion of patients receiving Impella significantly increased from 2016 to 2020 (6.5% versus 25.8%; P ‐trend<0.001). In‐hospital mortality was higher with ECMO with Impella (54.8%) compared with ECMO only (50.4%) and ECMO with IABP (48.4%). After adjustment, ECMO with IABP versus ECMO only was associated with lower in‐hospital mortality (adjusted odds ratio [aOR], 0.83; P =0.02). ECMO with Impella versus ECMO only had similar in‐hospital mortality (aOR, 1.09; P =0.695) but was associated with more bleeding (aOR, 1.21; P =0.007) and more acute kidney injury requiring hemodialysis (aOR, 1.42; P <0.001). ECMO with Impella versus ECMO with IABP was associated with greater risk of acute kidney injury requiring hemodialysis (aOR, 1.49; P =0.002), higher in‐hospital mortality (aOR, 1.32; P =0.001), and higher 40‐day mortality (hazard ratio, 1.25; P <0.001). Conclusions: In patients with cardiogenic shock on VA‐ECMO, LVU with Impella, particularly with 2.5/CP, was not associated with improved survival at 40 days but was associated with increased adverse events compared with IABP. More data are needed to assess Impella platform‐specific comparative outcomes of LVU.