46 research outputs found

    Legacy effect of fibrate add-on therapy in diabetic patients with dyslipidemia: a secondary analysis of the ACCORDION study.

    Get PDF
    BACKGROUND:The Action to Control Cardiovascular Risk in Diabetes (ACCORD)-Lipid study found no evidence of a beneficial effect of statin-fibrate combined treatment, compared to statins alone, on cardiovascular outcomes and mortality in type 2 diabetes mellitus after 5 years of active treatment. However, a beneficial reduction in major CVD events was shown in a pre-specified sub-group of participants with dyslipidemia. The extended follow-up of this trial provides the opportunity to further investigate possible beneficial effects of fibrates in this group of patients. We aimed to evaluate possible "legacy effects" of fibrate add-on therapy on mortality and major cardiovascular outcomes in patients with dyslipidemia. METHODS:The ACCORD-lipid study was a randomized controlled trial of 5518 participants assigned to receive simvastatin plus fenofibrate vs simvastatin plus placebo. After randomized treatment allocation had finished at the end of the trial, all surviving participants were invited to attend an extended follow-up study (ACCORDION) to continue prospective collection of clinical outcomes. We undertook a secondary analysis of trial and post-trial data in patients who had dyslipidemia. The primary outcome was all-cause and cardiovascular mortality, and secondary outcomes were nonfatal myocardial infarction, stroke, congestive heart failure and major coronary heart disease. We used an intention-to-treat approach to analysis to make comparisons between the original randomized treatment groups. RESULTS:853 participants with dyslipidemia had survived at the end of the trial. Most participants continued to use statins, but few used fibrates in either group during the post-trial period. The incidence rates in the fenofibrate group were lower with respect to all-cause mortality, CVD mortality, nonfatal myocardial infarction, congestive heart failure and major coronary heart disease than those in the placebo group over a post-trial follow-up. Allocation to the combined fibrate-statin treatment arm during the trial period had a beneficial legacy effect on all-cause mortality (adjusted HR = 0.65, 95% CI 0.45-0.94; P = 0.02). CONCLUSIONS:Fibrate treatment during the initial trial period was associated with a legacy benefit of improved survival over a post-trial follow-up. These findings support re-evaluation of fibrates as an add-on strategy to statins in order to reduce cardiovascular risk in diabetic patients with dyslipidemia. Trial registration clinicaltrials.gov, Identifier: NCT00000620

    Estimated legacy effects from simulated post-trial data were less biased than from combined trial/post-trial data

    Get PDF
    © 2019 Elsevier Inc. Objectives: “Legacy effects” describe the phenomena where treatment effects are apparent during the post-trial period that are not attributable to the direct effects observed within the trial. We investigate different approaches to analysis of trial and extended follow-up data for the evaluation of legacy effects. Study Design and Setting: We conducted a simulation to compare three approaches, which differed in terms of the time period and selection of trial participants included in the analysis. Results: The most common approach used for estimating legacy effects in the literature, which combines initial trial and post-trial follow-up data, gave the most biased estimates. Approaches using post–randomized controlled trial data had better performance in most scenarios. When the size of the legacy effect was set to differ according to whether or not drugs were taken after trial, the stratified approach using post-trial data but only from participants taking the drug after trial was less biased but often had lower power to detect a legacy effect. Conclusion: When estimating legacy effects, approaches to analysis that are restricted to post-trial follow-up data are preferred. If data are available on participant drug use after trial, then both stratified and unstratified approaches to analysis of the post-trial data should be investigated

    Monitoring adherence to drug treatment by using change in cholesterol concentration: Secondary analysis of trial data

    Get PDF
    Objective: To estimate the accuracy of monitoring cholesterol concentration for detecting non-adherence to lipid lowering treatment. Design: Secondary analysis of data on cholesterol concentration in the LIPID (long term intervention with pravastatin in ischaemic disease) study by using three measures of non-adherence: discontinuation of treatment, allocation to placebo arm, less than 80% of pills taken. Setting: Randomised placebo controlled trial in Australia and New Zealand. Participants: 9014 patients with previous coronary heart disease. Interventions: Pravastatin 40 mg or placebo daily. Main outcome measures: Sensitivity, specificity, area under the receiver operating characteristics (ROC) curve, post-test probability. Results: Monitoring of cholesterol concentration had modest ability for detecting complete non-adherence. One year after the start of treatment, half (1957/3937) of the non-adherent patients and 6% (253/3944) of adherent patients had a rise in concentration of low density lipoprotein cholesterol. Accuracy was reasonable (area under the curve 0.89). Cholesterol monitoring, however, had weak ability for detecting partial non-adherence. One year after the start of treatment,16%(34/213) of partially adherent and 4% (155/3585) of fully adherent patients had a rise in concentration of low density lipoprotein cholesterol. Accuracy was poor (area under the curve 0.65). For typical pre-test probabilities of non-adherence ranging from low (25%) to high (75%), the post-test probabilities indicate continuing uncertainty after lipid testing. A patient with no change in low density lipoprotein cholesterol concentration has a post-test probability of being completely non-adherent of between 67% and 95% and a post-test probability of being partially non-adherent of between 48% and 89%. A patient with a decrease in concentration of 1.0 mmol/L has a post-test probability of being completely non-adherent of between 7% and 40% and a post-test probability of being partially non-adherent of between 21% and 71%. Conclusions: Monitoring concentration of low density lipoprotein (or total) cholesterol has modest ability to detect complete non-adherence or non-persistence with pravastatin treatment and weak ability to detect partial non-adherence. Results of monitoring should be considered as no more than an adjunct to careful discussion with patients about adherence

    When to remeasure cardiovascular risk in untreated people at low and intermediate risk: Observational study

    Get PDF
    Objective: To estimate the probability of becoming high risk for cardiovascular disease among people at low and intermediate risk and not being treated for high blood pressure or lipid levels. Design: Observational study. Setting: General communities in Japan and the United States. Participants: 13 757 participants of the Tokyo health check-up study and 3855 of the Framingham studies aged 30-74 years with complete data on risk equation covariates, not receiving blood pressure or cholesterol lowering treatment, and with an estimated risk of cardiovascular disease 20% using the Framingham equation. Results: At baseline most participants had 10% probability of crossing the treatment threshold at one year for the 15-<20% baseline risk group. Conclusions: Decisions on the frequency of remeasuring for cardiovascular risk should be made on the basis of baseline risk. Repeat risk estimation before 8-10 years is not warranted for most people initially not requiring treatment. However, remeasurement within a year seems warranted in those with an initial 15-<20% risk

    Guidance for the design and reporting of studies evaluating the clinical performance of tests for present or past SARS-CoV-2 infection

    Get PDF
    Testing for SARS-CoV-2 infection is key in managing the current pandemic. More than 1700 preprints and peer reviewed journal articles evaluating tests for SARS-CoV-2 infection have been published as of January 2021. However, evaluations of these studies have identified many methodological issues, leading to a high risk of bias and difficulties applying the results in practice. Better guidance is urgently needed on the conduct and interpretation of these studies. This article outlines the principles for defining the intended purpose of the test; study population selection; reference standard, test timing; and other critical considerations for the design, reporting, and interpretation of diagnostic accuracy studies. The implementation and accuracy of SARS-CoV-2 tests have major implications for individuals and communities, balancing the potential consequences of continued infection against the need for public health measures, such as the restriction of movements and social activities. Decision making in the current pandemic requires a clear understanding of the clinical performance and limitations of testing. This article provides guidance to assist researchers design robust diagnostic accuracy studies, assist publishers and peer reviewers to assess such studies, and support clinicians and policy makers in their evaluation of the evidence on SARS-CoV-2 testing for clinical and public health decisions. The guidance aims to ensure that studies evaluating the diagnostic accuracy of SARS-CoV-2 tests are conducted as rigorously as possible, in an efficient and timely way

    Search for gravitational waves from Scorpius X-1 in the second Advanced LIGO observing run with an improved hidden Markov model

    Get PDF
    We present results from a semicoherent search for continuous gravitational waves from the low-mass x-ray binary Scorpius X-1, using a hidden Markov model (HMM) to track spin wandering. This search improves on previous HMM-based searches of LIGO data by using an improved frequency domain matched filter, the J-statistic, and by analyzing data from Advanced LIGO's second observing run. In the frequency range searched, from 60 to 650 Hz, we find no evidence of gravitational radiation. At 194.6 Hz, the most sensitive search frequency, we report an upper limit on gravitational wave strain (at 95% confidence) of h095%=3.47×10-25 when marginalizing over source inclination angle. This is the most sensitive search for Scorpius X-1, to date, that is specifically designed to be robust in the presence of spin wandering. © 2019 American Physical Society

    Search for gravitational waves from Scorpius X-1 in the second Advanced LIGO observing run with an improved hidden Markov model

    Get PDF
    We present results from a semicoherent search for continuous gravitational waves from the low-mass x-ray binary Scorpius X-1, using a hidden Markov model (HMM) to track spin wandering. This search improves on previous HMM-based searches of LIGO data by using an improved frequency domain matched filter, the J-statistic, and by analyzing data from Advanced LIGO’s second observing run. In the frequency range searched, from 60 to 650 Hz, we find no evidence of gravitational radiation. At 194.6 Hz, the most sensitive search frequency, we report an upper limit on gravitational wave strain (at 95% confidence) of h95%0=3.47×10−25 when marginalizing over source inclination angle. This is the most sensitive search for Scorpius X-1, to date, that is specifically designed to be robust in the presence of spin wandering
    corecore