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1.
Nat Commun ; 14(1): 7374, 2023 11 15.
Article En | MEDLINE | ID: mdl-37968269

Choosing optimal outcome measures maximizes statistical power, accelerates discovery and improves reliability in early-phase trials. We devised and evaluated a modification to a pragmatic measure of oxygenation function, the [Formula: see text] ratio. Because of the ceiling effect in oxyhaemoglobin saturation, [Formula: see text] ratio ceases to reflect pulmonary oxygenation function at high [Formula: see text] values. We found that the correlation of [Formula: see text] with the reference standard ([Formula: see text]/[Formula: see text] ratio) improves substantially when excluding [Formula: see text] and refer to this measure as [Formula: see text]. Using observational data from 39,765 hospitalised COVID-19 patients, we demonstrate that [Formula: see text] is predictive of mortality, and compare the sample sizes required for trials using four different outcome measures. We show that a significant difference in outcome could be detected with the smallest sample size using [Formula: see text]. We demonstrate that [Formula: see text] is an effective intermediate outcome measure in COVID-19. It is a non-invasive measurement, representative of disease severity and provides greater statistical power.


COVID-19 , Humans , Reproducibility of Results , COVID-19/diagnosis , Lung , Sample Size
2.
Eur Heart J Qual Care Clin Outcomes ; 9(4): 377-388, 2023 06 21.
Article En | MEDLINE | ID: mdl-36385522

BACKGROUND: Although morbidity and mortality from COVID-19 have been widely reported, the indirect effects of the pandemic beyond 2020 on other major diseases and health service activity have not been well described. METHODS AND RESULTS: Analyses used national administrative electronic hospital records in England, Scotland, and Wales for 2016-21. Admissions and procedures during the pandemic (2020-21) related to six major cardiovascular conditions [acute coronary syndrome (ACS), heart failure (HF), stroke/transient ischaemic attack (TIA), peripheral arterial disease (PAD), aortic aneurysm (AA), and venous thromboembolism(VTE)] were compared with the annual average in the pre-pandemic period (2016-19). Differences were assessed by time period and urgency of care.In 2020, there were 31 064 (-6%) fewer hospital admissions [14 506 (-4%) fewer emergencies, 16 560 (-23%) fewer elective admissions] compared with 2016-19 for the six major cardiovascular diseases (CVDs) combined. The proportional reduction in admissions was similar in all three countries. Overall, hospital admissions returned to pre-pandemic levels in 2021. Elective admissions remained substantially below expected levels for almost all conditions in all three countries [-10 996 (-15%) fewer admissions]. However, these reductions were offset by higher than expected total emergency admissions [+25 878 (+6%) higher admissions], notably for HF and stroke in England, and for VTE in all three countries. Analyses for procedures showed similar temporal variations to admissions. CONCLUSION: The present study highlights increasing emergency cardiovascular admissions during the pandemic, in the context of a substantial and sustained reduction in elective admissions and procedures. This is likely to increase further the demands on cardiovascular services over the coming years.


COVID-19 , Cardiovascular Diseases , Heart Failure , Stroke , Venous Thromboembolism , Humans , COVID-19/epidemiology , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/therapy , Pandemics , Secondary Care , Electronic Health Records , England/epidemiology , Stroke/epidemiology
3.
Lancet ; 400(10355): 822-831, 2022 09 10.
Article En | MEDLINE | ID: mdl-36049495

BACKGROUND: Angiotensin receptor blockers (ARBs) and ß blockers are widely used in the treatment of Marfan syndrome to try to reduce the rate of progressive aortic root enlargement characteristic of this condition, but their separate and joint effects are uncertain. We aimed to determine these effects in a collaborative individual patient data meta-analysis of randomised trials of these treatments. METHODS: In this meta-analysis, we identified relevant trials of patients with Marfan syndrome by systematically searching MEDLINE, Embase, and CENTRAL from database inception to Nov 2, 2021. Trials were eligible if they involved a randomised comparison of an ARB versus control or an ARB versus ß blocker. We used individual patient data from patients with no prior aortic surgery to estimate the effects of: ARB versus control (placebo or open control); ARB versus ß blocker; and indirectly, ß blocker versus control. The primary endpoint was the annual rate of change of body surface area-adjusted aortic root dimension Z score, measured at the sinuses of Valsalva. FINDINGS: We identified ten potentially eligible trials including 1836 patients from our search, from which seven trials and 1442 patients were eligible for inclusion in our main analyses. Four trials involving 676 eligible participants compared ARB with control. During a median follow-up of 3 years, allocation to ARB approximately halved the annual rate of change in the aortic root Z score (mean annual increase 0·07 [SE 0·02] ARB vs 0·13 [SE 0·02] control; absolute difference -0·07 [95% CI -0·12 to -0·01]; p=0·012). Prespecified secondary subgroup analyses showed that the effects of ARB were particularly large in those with pathogenic variants in fibrillin-1, compared with those without such variants (heterogeneity p=0·0050), and there was no evidence to suggest that the effect of ARB varied with ß-blocker use (heterogeneity p=0·54). Three trials involving 766 eligible participants compared ARBs with ß blockers. During a median follow-up of 3 years, the annual change in the aortic root Z score was similar in the two groups (annual increase -0·08 [SE 0·03] in ARB groups vs -0·11 [SE 0·02] in ß-blocker groups; absolute difference 0·03 [95% CI -0·05 to 0·10]; p=0·48). Thus, indirectly, the difference in the annual change in the aortic root Z score between ß blockers and control was -0·09 (95% CI -0·18 to 0·00; p=0·042). INTERPRETATION: In people with Marfan syndrome and no previous aortic surgery, ARBs reduced the rate of increase of the aortic root Z score by about one half, including among those taking a ß blocker. The effects of ß blockers were similar to those of ARBs. Assuming additivity, combination therapy with both ARBs and ß blockers from the time of diagnosis would provide even greater reductions in the rate of aortic enlargement than either treatment alone, which, if maintained over a number of years, would be expected to lead to a delay in the need for aortic surgery. FUNDING: Marfan Foundation, the Oxford British Heart Foundation Centre for Research Excellence, and the UK Medical Research Council.


Marfan Syndrome , Adrenergic beta-Antagonists/therapeutic use , Angiotensin Receptor Antagonists/therapeutic use , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Aorta , Humans , Marfan Syndrome/complications , Marfan Syndrome/drug therapy , Randomized Controlled Trials as Topic
5.
Lancet Gastroenterol Hepatol ; 6(3): 199-208, 2021 03.
Article En | MEDLINE | ID: mdl-33453763

BACKGROUND: There are concerns that the COVID-19 pandemic has had a negative effect on cancer care but there is little direct evidence to quantify any effect. This study aims to investigate the impact of the COVID-19 pandemic on the detection and management of colorectal cancer in England. METHODS: Data were extracted from four population-based datasets spanning NHS England (the National Cancer Cancer Waiting Time Monitoring, Monthly Diagnostic, Secondary Uses Service Admitted Patient Care and the National Radiotherapy datasets) for all referrals, colonoscopies, surgical procedures, and courses of rectal radiotherapy from Jan 1, 2019, to Oct 31, 2020, related to colorectal cancer in England. Differences in patterns of care were investigated between 2019 and 2020. Percentage reductions in monthly numbers and proportions were calculated. FINDINGS: As compared to the monthly average in 2019, in April, 2020, there was a 63% (95% CI 53-71) reduction (from 36 274 to 13 440) in the monthly number of 2-week referrals for suspected cancer and a 92% (95% CI 89-95) reduction in the number of colonoscopies (from 46 441 to 3484). Numbers had just recovered by October, 2020. This resulted in a 22% (95% CI 8-34) relative reduction in the number of cases referred for treatment (from a monthly average of 2781 in 2019 to 2158 referrals in April, 2020). By October, 2020, the monthly rate had returned to 2019 levels but did not exceed it, suggesting that, from April to October, 2020, over 3500 fewer people had been diagnosed and treated for colorectal cancer in England than would have been expected. There was also a 31% (95% CI 19-42) relative reduction in the numbers receiving surgery in April, 2020, and a lower proportion of laparoscopic and a greater proportion of stoma-forming procedures, relative to the monthly average in 2019. By October, 2020, laparoscopic surgery and stoma rates were similar to 2019 levels. For rectal cancer, there was a 44% (95% CI 17-76) relative increase in the use of neoadjuvant radiotherapy in April, 2020, relative to the monthly average in 2019, due to greater use of short-course regimens. Although in June, 2020, there was a drop in the use of short-course regimens, rates remained above 2019 levels until October, 2020. INTERPRETATION: The COVID-19 pandemic has led to a sustained reduction in the number of people referred, diagnosed, and treated for colorectal cancer. By October, 2020, achievement of care pathway targets had returned to 2019 levels, albeit with smaller volumes of patients and with modifications to usual practice. As pressure grows in the NHS due to the second wave of COVID-19, urgent action is needed to address the growing burden of undetected and untreated colorectal cancer in England. FUNDING: Cancer Research UK, the Medical Research Council, Public Health England, Health Data Research UK, NHS Digital, and the National Institute for Health Research Oxford Biomedical Research Centre.


COVID-19 , Colonoscopy/statistics & numerical data , Colorectal Neoplasms , Colorectal Surgery/statistics & numerical data , Early Detection of Cancer , Patient Care Management , Radiotherapy/statistics & numerical data , COVID-19/epidemiology , COVID-19/prevention & control , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/epidemiology , Colorectal Neoplasms/therapy , Delivery of Health Care/trends , Early Detection of Cancer/methods , Early Detection of Cancer/statistics & numerical data , England/epidemiology , Female , Health Services Needs and Demand , Humans , Male , Middle Aged , Patient Care Management/methods , Patient Care Management/organization & administration , Patient Care Management/standards , Referral and Consultation/statistics & numerical data , SARS-CoV-2 , State Medicine
6.
Lancet ; 396(10248): 381-389, 2020 08 08.
Article En | MEDLINE | ID: mdl-32679111

BACKGROUND: Several countries affected by the COVID-19 pandemic have reported a substantial drop in the number of patients attending the emergency department with acute coronary syndromes and a reduced number of cardiac procedures. We aimed to understand the scale, nature, and duration of changes to admissions for different types of acute coronary syndrome in England and to evaluate whether in-hospital management of patients has been affected as a result of the COVID-19 pandemic. METHODS: We analysed data on hospital admissions in England for types of acute coronary syndrome from Jan 1, 2019, to May 24, 2020, that were recorded in the Secondary Uses Service Admitted Patient Care database. Admissions were classified as ST-elevation myocardial infarction (STEMI), non-STEMI (NSTEMI), myocardial infarction of unknown type, or other acute coronary syndromes (including unstable angina). We identified revascularisation procedures undertaken during these admissions (ie, coronary angiography without percutaneous coronary intervention [PCI], PCI, and coronary artery bypass graft surgery). We calculated the numbers of weekly admissions and procedures undertaken; percentage reductions in weekly admissions and across subgroups were also calculated, with 95% CIs. FINDINGS: Hospital admissions for acute coronary syndrome declined from mid-February, 2020, falling from a 2019 baseline rate of 3017 admissions per week to 1813 per week by the end of March, 2020, a reduction of 40% (95% CI 37-43). This decline was partly reversed during April and May, 2020, such that by the last week of May, 2020, there were 2522 admissions, representing a 16% (95% CI 13-20) reduction from baseline. During the period of declining admissions, there were reductions in the numbers of admissions for all types of acute coronary syndrome, including both STEMI and NSTEMI, but relative and absolute reductions were larger for NSTEMI, with 1267 admissions per week in 2019 and 733 per week by the end of March, 2020, a percent reduction of 42% (95% CI 38-46). In parallel, reductions were recorded in the number of PCI procedures for patients with both STEMI (438 PCI procedures per week in 2019 vs 346 by the end of March, 2020; percent reduction 21%, 95% CI 12-29) and NSTEMI (383 PCI procedures per week in 2019 vs 240 by the end of March, 2020; percent reduction 37%, 29-45). The median length of stay among patients with acute coronary syndrome fell from 4 days (IQR 2-9) in 2019 to 3 days (1-5) by the end of March, 2020. INTERPRETATION: Compared with the weekly average in 2019, there was a substantial reduction in the weekly numbers of patients with acute coronary syndrome who were admitted to hospital in England by the end of March, 2020, which had been partly reversed by the end of May, 2020. The reduced number of admissions during this period is likely to have resulted in increases in out-of-hospital deaths and long-term complications of myocardial infarction and missed opportunities to offer secondary prevention treatment for patients with coronary heart disease. The full extent of the effect of COVID-19 on the management of patients with acute coronary syndrome will continue to be assessed by updating these analyses. FUNDING: UK Medical Research Council, British Heart Foundation, Public Health England, Health Data Research UK, and the National Institute for Health Research Oxford Biomedical Research Centre.


Acute Coronary Syndrome/therapy , Coronavirus Infections/epidemiology , Hospitalization/statistics & numerical data , Pandemics , Pneumonia, Viral/epidemiology , Aged , Aged, 80 and over , Angina, Unstable/therapy , Betacoronavirus , COVID-19 , England/epidemiology , Facilities and Services Utilization , Female , Humans , Male , Middle Aged , Myocardial Revascularization , Non-ST Elevated Myocardial Infarction/therapy , SARS-CoV-2 , ST Elevation Myocardial Infarction/therapy
7.
Lancet Gastroenterol Hepatol ; 3(4): 231-241, 2018 04.
Article En | MEDLINE | ID: mdl-29475806

BACKGROUND: Gastroprotectant drugs are used for the prevention and treatment of peptic ulcer disease and might reduce its associated complications, but reliable estimates of the effects of gastroprotectants in different clinical settings are scarce. We aimed to examine the effects of proton-pump inhibitors (PPIs), prostaglandin analogues, and histamine-2 receptor antagonists (H2RAs) in different clinical circumstances by doing meta-analyses of tabular data from all relevant unconfounded randomised trials of gastroprotectant drugs. METHODS: We searched MEDLINE and Embase from Jan 1, 1950, to Dec 31, 2015, to identify unconfounded, randomised trials of a gastroprotectant drug (defined as a PPI, prostaglandin analogue, or H2RA) versus control, or versus another gastroprotectant. Two independent researchers reviewed the search results and extracted the prespecified outcomes and key characteristics for each trial. We did meta-analyses of the effects of gastroprotectant drugs on ulcer development, bleeding, and mortality overall, according to the class of gastroprotectant, and according to the individual drug within a gastroprotectant class. FINDINGS: We identified comparisons of gastroprotectant versus control in 849 trials (142 485 participants): 580 prevention trials (110 626 participants), 233 healing trials (24 033 participants), and 36 trials for the treatment of acute upper gastrointestinal bleeding (7826 participants). Comparisons of one gastroprotectant drug versus another were available in 345 trials (64 905 participants), comprising 160 prevention trials (32 959 participants), 167 healing trials (28 306 participants), and 18 trials for treatment of acute upper gastrointestinal bleeding (3640 participants). The median number of patients in each trial was 78 (IQR 44·0-210·5) and the median duration was 1·4 months (0·9-2·8). In prevention trials, gastroprotectant drugs reduced development of endoscopic ulcers (odds ratio [OR] 0·27, 95% CI 0·25-0·29; p<0·0001), symptomatic ulcers (0·25, 0·22-0·29; p<0·0001), and upper gastrointestinal bleeding (0·40, 0·32-0·50; p<0·0001), but did not significantly reduce mortality (0·85, 0·69-1·04; p=0·11). Larger proportional reductions in upper gastrointestinal bleeding were observed for PPIs than for other gastroprotectant drugs (PPIs 0·21, 99% CI 0·12-0·36; prostaglandin analogues 0·63, 0·35-1·12; H2RAs 0·49, 0·30-0·80; phet=0·0005). Gastroprotectant drugs were effective in preventing bleeding irrespective of the use of non-steroidal anti-inflammatory drugs (phet=0·56). In healing trials, gastroprotectants increased endoscopic ulcer healing (3·49, 95% CI 3·28-3·72; p<0·0001), with PPIs more effective (5·22, 99% CI 4·00-6·80) than prostaglandin analogues (2·27, 1·91-2·70) and H2RAs (3·80, 3·44-4·20; phet<0·0001). In trials among patients with acute bleeding, gastroprotectants reduced further bleeding (OR 0·68, 95% CI 0·60-0·78; p<0·0001), blood transfusion (0·75, 0·65-0·88; p=0·0003), further endoscopic intervention (0·56, 0·45-0·70; p<0·0001), and surgery (0·72, 0·61-0·84; p<0·0001), but did not significantly reduce mortality (OR 0·90, 0·72-1·11; p=0·31). PPIs had larger protective effects than did H2RAs for further bleeding (phet=0·0107) and blood transfusion (phet=0·0130). INTERPRETATION: Gastroprotectants, in particular PPIs, reduce the risk of peptic ulcer disease and its complications and promote healing of peptic ulcers in a wide range of clinical circumstances. However, this meta-analysis might have overestimated the benefits owing to small study bias. FUNDING: UK Medical Research Council and the British Heart Foundation.


Anti-Ulcer Agents/therapeutic use , Histamine H2 Antagonists/therapeutic use , Peptic Ulcer Hemorrhage/drug therapy , Peptic Ulcer/drug therapy , Peptic Ulcer/prevention & control , Prostaglandins, Synthetic/therapeutic use , Proton Pump Inhibitors/therapeutic use , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Humans , Peptic Ulcer/complications , Peptic Ulcer Hemorrhage/prevention & control , Secondary Prevention
8.
Stat Methods Med Res ; 26(5): 2287-2318, 2017 Oct.
Article En | MEDLINE | ID: mdl-26271918

We investigate the effect of the choice of parameterisation of meta-analytic models and related uncertainty on the validation of surrogate endpoints. Different meta-analytical approaches take into account different levels of uncertainty which may impact on the accuracy of the predictions of treatment effect on the target outcome from the treatment effect on a surrogate endpoint obtained from these models. A range of Bayesian as well as frequentist meta-analytical methods are implemented using illustrative examples in relapsing-remitting multiple sclerosis, where the treatment effect on disability worsening is the primary outcome of interest in healthcare evaluation, while the effect on relapse rate is considered as a potential surrogate to the effect on disability progression, and in gastric cancer, where the disease-free survival has been shown to be a good surrogate endpoint to the overall survival. Sensitivity analysis was carried out to assess the impact of distributional assumptions on the predictions. Also, sensitivity to modelling assumptions and performance of the models were investigated by simulation. Although different methods can predict mean true outcome almost equally well, inclusion of uncertainty around all relevant parameters of the model may lead to less certain and hence more conservative predictions. When investigating endpoints as candidate surrogate outcomes, a careful choice of the meta-analytical approach has to be made. Models underestimating the uncertainty of available evidence may lead to overoptimistic predictions which can then have an effect on decisions made based on such predictions.


Bayes Theorem , Biomarkers , Endpoint Determination/methods , Meta-Analysis as Topic , Biomarkers/analysis , Endpoint Determination/statistics & numerical data , Humans , Models, Statistical , Recurrence , Treatment Outcome , Uncertainty
9.
Pediatrics ; 134(1): e55-62, 2014 Jul.
Article En | MEDLINE | ID: mdl-24982100

BACKGROUND: The Parent Report of Children's Abilities-Revised (PARCA-R) is a questionnaire for assessing cognitive and language development in very preterm infants. Given the increased risk of developmental delay in infants born late and moderately preterm (LMPT; 32-36 weeks), this study aimed to validate this questionnaire as a screening tool in this population. METHODS: Parents of 219 children born LMPT completed the PARCA-R questionnaire and the Brief Infant Toddler Social and Emotional Assessment when children were 24 months corrected age (range, 24 months-27 months). The children were subsequently assessed by using the cognitive and language scales of the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III). RESULTS: An average Bayley-III, cognitive and language (CB-III) score and a total PARCA-R Parent Report Composite (PRC) score were computed. There was a large association between PRC and CB-III scores (r = 0.66, P < .001) indicating good concurrent validity. Using Youden index, the optimum PARCA-R cutoff for identifying children with moderate/severe developmental delay (CB-III scores < 80) was PRC scores < 73. This gave sensitivity 0.90 (95% confidence interval: 0.75-1.00) and specificity 0.76 (95% confidence interval: 0.70-0.82), indicating good diagnostic utility. Approximately two-thirds of the children who had a PRC score < 73 had false-positive screens. However, these children had significantly poorer cognitive and behavioral outcomes than children with true negative screens. CONCLUSIONS: The PARCA-R has good concurrent validity with a gold standard developmental test and can be used to identify LMPT infants who may benefit from a clinical assessment. The PARCA-R has potential for clinical use as a first-line cognitive screening tool for this sizeable population of infants in whom follow-up may be beneficial.


Developmental Disabilities/diagnosis , Infant, Postmature , Infant, Premature , Parents , Surveys and Questionnaires , Child, Preschool , Female , Humans , Infant, Newborn , Male
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