Applying results from clinical trials: tranexamic acid in trauma patients.

This paper considers how results from clinical trials should be applied in the care of patients, using the results of the Clinical Randomisation of an Antifibrinolytic in Significant Haemorrhage (CRASH-2) trial of tranexamic acid in bleeding trauma patients as a case study. We explain why an understanding of the mechanisms of action of the trial treatment, and insight into the factors that might be relevant to this mechanism, is critical in order to properly apply (generalise) trial results and why it is not necessary that the trial population is representative of the population in which the medicine will be used. We explain why cause (mechanism)-specific mortality is more generalizable than all-cause mortality and why the risk ratio is the generalizable measure of the effect of the treatment. Overall, we argue that a biological insight into how the treatment works is more relevant when applying research results to patient care than the application of statistical reasoning

Mechanism of action of tranexamic acid in bleeding trauma patients: an exploratory analysis of data from the CRASH-2 trial.

INTRODUCTION: To investigate the mechanism of action of tranexamic acid (TXA) in bleeding trauma patients, we examined the timing of its effect on mortality. We hypothesised that if TXA reduces mortality by decreasing blood loss, its effect should be greatest on the day of the injury when bleeding is most profuse. However, if TXA reduces mortality via an anti-inflammatory mechanism its effect should be greater over the subsequent days. METHODS: Exploratory analysis, including per-protocol analyses, of data from the CRASH-2 trial, a randomised placebo controlled trial of the effect of TXA on mortality in 20,211 trauma patients with, or at risk of, significant bleeding. We examined hazard ratios (HR) and 95% confidence intervals for all-cause mortality, deaths due to bleeding and non-bleeding deaths, according to the day since injury. The CRASH-2 trial is registered as ISRCTN86750102 and ClinicalTrials.gov NCT00375258. RESULTS: The effect of TXA on mortality is greatest for deaths occurring on the day of the injury (HR all-cause mortality = 0.83, 0.73 to 0.93). This survival benefit is only evident in patients in whom treatment is initiated within 3 hours of their injury (HR ≤ 3 hours = 0.78, 0.68 to 0.90; HR > 3 hours = 1.02, 0.76 to 1.36). Initiation of TXA treatment within 3 hours of injury reduced the hazard of death due to bleeding on the day of the injury by 28% (HR = 0.72, 0.60 to 0.86). TXA treatment initiated beyond 3 hours of injury appeared to increase the hazard of death due to bleeding, although the estimates were imprecise. CONCLUSIONS: Early administration of tranexamic acid appears to reduce mortality primarily by preventing exsanguination on the day of the injury

Effect of changes in moderate or vigorous physical activity on changes in health-related quality of life of elderly British women over seven years.

PURPOSE: This study investigates the effect of changes in moderate or vigorous physical activity (MVPA) on trajectories in health-related quality of life (HR-QoL) over 7 years in British elderly women. METHODS: A total of 1,926 women from the British Women's Heart and Health Study with information on MVPA and HR-QoL [measured using Euro quality of life 5 dimension (EQ-5D)] at baseline and at 7 years of follow-up were included in the analysis. Baseline and 7-year follow-up MVPA values were categorised into 3 groups, generating 9 categories of change in MVPA. Logistic regression was used to obtain odds ratios (ORs) of maintaining or improving HR-QoL according to different patterns of change in MVPA level. RESULTS: Women who remained inactive over the 7 years of follow-up had the largest reduction in their EQ-5D scores. Compared to these women, women that increased their MPVA level from "inactive" to "low" or to "moderate-high" were more likely to maintain or improve their HR-QoL over 7 years (ORs 1.65 or 2.70, respectively, p value for trend <0.001). After adjustment for baseline EQ-5D score and a wide range of potential confounders, results remained largely unchanged, though precision of the estimates generally decreased. CONCLUSIONS: Our findings suggest that relatively regular MVPA, even taken up later in life, can help older women prevent a decline in HR-QoL and even improve their enjoyment of life

Effect of changes in moderate or vigorous physical activity on changes in health-related quality of life of elderly British women over seven years.

PURPOSE: This study investigates the effect of changes in moderate or vigorous physical activity (MVPA) on trajectories in health-related quality of life (HR-QoL) over 7 years in British elderly women. METHODS: A total of 1,926 women from the British Women's Heart and Health Study with information on MVPA and HR-QoL [measured using Euro quality of life 5 dimension (EQ-5D)] at baseline and at 7 years of follow-up were included in the analysis. Baseline and 7-year follow-up MVPA values were categorised into 3 groups, generating 9 categories of change in MVPA. Logistic regression was used to obtain odds ratios (ORs) of maintaining or improving HR-QoL according to different patterns of change in MVPA level. RESULTS: Women who remained inactive over the 7 years of follow-up had the largest reduction in their EQ-5D scores. Compared to these women, women that increased their MPVA level from "inactive" to "low" or to "moderate-high" were more likely to maintain or improve their HR-QoL over 7 years (ORs 1.65 or 2.70, respectively, p value for trend <0.001). After adjustment for baseline EQ-5D score and a wide range of potential confounders, results remained largely unchanged, though precision of the estimates generally decreased. CONCLUSIONS: Our findings suggest that relatively regular MVPA, even taken up later in life, can help older women prevent a decline in HR-QoL and even improve their enjoyment of life

The Role of Topical Timolol in the Treatment of Infantile Hemangiomas: A Systematic Review and Meta-analysis.

To date the efficacy and safety of topical timolol in the treatment of infantile hemangioma has not been reviewed and analysed systematically. We collated all published data on the efficacy and safety of topical timolol in the treatment of infantile hemangioma. A total of 31 studies with 691 patients were included. The fixed effects pooled estimate of the response rate defined as any improvement from baseline of infantile hemangioma after treatment with topical timolol was significant (RR = 8.96; 95% CI 5.07-15.47; heterogeneity test p = 0.99), and the treatment was overall well tolerated. However, the quality of evidence was low to moderate. Topical timolol is an effective treatment for small infantile hemangioma, with no significant adverse effects noted. However, there is still a need for adequately powered randomised controlled trials

Cambios en los parámetros vocales de los docentes durante el curso escolar

La voz es una herramienta fundamental para el docente. La alteración de sus cualidades básicas es definida como disfonía y resulta ser muy común. Nuestro objetivo es estudiar si la voz de los docentes cambia, como consecuencia del esfuerzo vocal provocado por su profesión, en los trimestres del curso escolar y tras la jornada laboral, midiendo el índice acústico de calidad de voz (AVQI). Además, estudiamos si el cambio tras la jornada laboral difiere en los distintos trimestres del curso. La muestra está compuesta de 93 docentes de los cuales 40 imparten su labor en un centro público y 53 en un centro concertado. Por sexos, el 29% son hombres y el 71% son mujeres. El 41.4% imparte en infantil y/o primaria y el 58.6% en ESO y/o Bachillerato. Para la grabación de voz se utilizó el programa de análisis acústico PRAAT. Se encuentran evidencias de que en el segundo y tercer trimestre el parámetro AVQI empeora en los docentes de forma significativa tras su jornada lectiva y de forma más acusada en los que imparten ESO y Bachillerato. Los docentes de centros públicos registran niveles AVQI significativamente superiores a los de centros concertados. La disfonía es significativamente menor en los docentes que imparten las materias de música, idioma distinto del castellano y/o educación física. No se encuentran cambios significativos de AVQI entre los distintos trimestres

Hidden heterogeneity: Uncovering patterns of adherence in microbicide trials for HIV prevention.

BACKGROUND: Interpretation of clinical trial results testing vaginal microbicide gels for HIV prevention depends on participant adherence. Prior to the era of antiretrovirals, microbicide trials collected adherence data via self-report, and trials typically reported trial population adherence as overall averages in primary results manuscripts. This study first sought to determine if different patterns of adherence from three trials of vaginal microbicide gels could be identified, using self-reported data and if so, how those patterns compare across trials. The second objective was to explore which individual-level factors were associated with different adherence patterns. METHODS: Data from the following three clinical trials of vaginal microbicides were used for this study: HIV Prevention Trials Network (HPTN) 035 testing PRO 2000 and Buffergel, the Microbicides Development Programme (MDP) 301 testing PRO 2000, and the Population Council's Carraguard study, testing Carraguard gel. Latent Class Analysis (LCA) was used to identify longitudinal patterns of adherence using self-reported data about gel use. Multinomial multivariable logistic regression was used to estimate relative risk-ratios for factors which were independently associated with different latent adherence trajectories within each trial, and compared across trials. RESULTS: Included in this analysis are 2,282 women from HPTN 035 (age 17-56 years), 6238 women from MDP 301 (age 16-75 years), and 6039 women from Carraguard (age 16-73 years). Using LCA, 3-4 different patterns of gel adherence were identified in each trial; these patterns were similar across the trials. Factors associated with adherence patterns were identified in all trials. Older age was associated with the adherence trajectory that consistently reported gel use in three trials. Participant-reported negative reaction of partners to the gel was associated with trajectories that reported less consistent adherence in two trials. A greater number of baseline-reported sex partners or sex acts was associated with trajectories which reported less consistent adherence in some trials. Trial site location was associated with membership of trajectories in all trials. CONCLUSION: LCA was able to identify patterns of microbicide gel adherence in clinical trials that used self-reported data. Key factors associated with patterns of adherence in this study were participant age, clinical trial site location, and partner reaction to the study gel. These findings, in particular, age and perceived partner reaction to the method, are consistent with results from other clinical trials and programmatic rollout of biomedical HIV prevention methods for women in Africa. This study contributes to the body of evidence that women need more support to navigate power dynamics within their relationships with men so that they can successfully use HIV prevention methods

Unintended effects of statins from observational studies in the general population: systematic review and meta-analysis.

BACKGROUND: Efficacy of statins has been extensively studied, with much less information reported on their unintended effects. Evidence from randomized controlled trials (RCTs) on unintended effects is often insufficient to support hypotheses generated from observational studies. We aimed to systematically assess unintended effects of statins from observational studies in general populations with comparison of the findings where possible with those derived from randomized trials. METHODS: Medline (1998 to January 2012, week 3) and Embase (1998 to 2012, week 6) were searched using the standard BMJ Cohort studies filter. The search was supplemented with reference lists of all identified studies and contact with experts in the field. We included prospective studies with a sample size larger than 1,000 participants, case control (of any size) and routine health service linkage studies of over at least one year duration. Studies in subgroups of patients or follow-up of patient case series were excluded, as well as hospital-based cohort studies. RESULTS: Ninety studies were identified, reporting on 48 different unintended effects. Statins were associated with lower risks of dementia and cognitive impairment, venous thrombo-embolism, fractures and pneumonia, but these findings were attenuated in analyses restricted to higher quality studies (respectively: OR 0.74 (95% CI 0.62 to 0.87); OR 0.92 (95% CI 0.81 to 1.03); OR 0.97 (95% CI 0.88 to 1.05); OR 0.92 (95% CI 0.83 to 1.02)); and marked heterogeneity of effects across studies remained. Statin use was not related to any increased risk of depression, common eye diseases, renal disorders or arthritis. There was evidence of an increased risk of myopathy, raised liver enzymes and diabetes (respectively: OR 2.63 (95% CI 1.50 to 4.61); OR 1.54 (95% CI 1.47 to 1.62); OR 1.31 (95% CI 0.99 to 1.73)). CONCLUSIONS: Our systematic review and meta-analyses indicate that high quality observational data can provide relevant evidence on unintended effects of statins to add to the evidence from RCTs. The absolute excess risk of the observed harmful unintended effects of statins is very small compared to the beneficial effects of statins on major cardiovascular events

Lung, gastric and colorectal cancer mortality by occupation and industry among working-aged men in Japan

We examined occupational and industrial differences in lung, gastric, and colorectal cancer risk among Japanese men of working age (25–64 years) using the 2010 Japanese national survey data for occupation and industry-specific death rates. Poisson regression models were used to estimate the age-adjusted incident rate ratios by lung, gastric, and colorectal cancers, with manufacturing used as the referent occupation or industry. Unemployed Japanese men and those in manufacturing had an 8–11-fold increased risk of lung, gastric and colorectal cancer. The highest mortality rates for lung and colorectal cancer by occupation were “administrative and managerial” (by occupation) and “mining” (by industry). For gastric cancer, the highest mortality rate was “agriculture” (by occupation) and “mining” (by industry). By occupation; Japanese men in service occupations, those in administrative and managerial positions, those in agriculture, forestry and fisheries, and those in professional and engineering categories had higher relative mortality risks for lung, gastric, and colorectal cancers. By industry; mining, electricity and gas, fisheries, and agriculture and forestry had the higher mortality risks for those cancers. Unemployed men had higher mortality rates than men in any occupation and industry for all three cancers. Overall, this study suggests that for Japanese men, occupations and industries may be a key social determinant of health