Two clinical trials, one British and one American, have shown that early, prophylactic elective surgery does not improve five-year survival among patients with small abdominal aortic aneurysms. We ...report long-term outcomes in the United Kingdom Small Aneurysm Trial.
We randomly assigned 1090 patients, 60 to 76 years of age, with small abdominal aortic aneurysms (diameter, 4.0 to 5.5 cm) to one of two groups: 563 were assigned to undergo early elective surgery, and 527 were assigned to undergo surveillance by ultrasonography. Patients were followed in the trial until June 1998 and thereafter until August 2001; the mean duration of follow-up was 8 years (range, 6 to 10).
The mean duration of survival was 6.5 years among patients in the surveillance group, as compared with 6.7 years among patients in the early-surgery group (P=0.29). The adjusted hazard ratio for death from any cause in the early-surgery group as compared with the surveillance group was 0.83 (95 percent confidence interval, 0.69 to 1.00; P=0.05). The 30-day operative mortality in the early-surgery group (5.5 percent) led to an early disadvantage in terms of survival. The survival curves crossed at three years, and at eight years, mortality in the early-surgery group was 7.2 percentage points lower than that in the surveillance group (P=0.03). There was no evidence that age, sex, or the initial size of the aneurysm modified the hazard ratio or that delayed surgery in the surveillance group increased 30-day postoperative mortality. Death was attributable to a ruptured aneurysm in 19 of the 411 men who died (5 percent) and in 12 of the 85 women who died (14 percent) (P=0.001). The rate of early cessation of smoking was higher in the early-surgery group than in the surveillance group.
Among patients with a small abdominal aortic aneurysm, we found no long-term difference in mean survival between the early-surgery and surveillance groups, although after eight years, total mortality was lower in the early-surgery group. This difference may be attributed in part to beneficial changes in lifestyle adopted by members of the early-surgery group.
Our purpose was to document and investigate the prognostic significance of features seen on MRI of patients with whiplash injury following relatively minor road traffic crashes. MRI was obtained ...shortly and at 6 months after the crash using a 0.5 T imager. The images were assessed independently by two radiologists for evidence of fracture or other injury; loss of lordosis and spondylosis were also recorded. Clinical examinations were used to assess the status of patients initially and at 6 months. The results of the independent MRI and clinical investigations were then examined for association using statistical tests. Initial MRI was performed on 29 patients, of whom 19 had repeat studies at 6 months; 48 examinations were thus examined. Apart from spondylosis and loss of lordosis, only one abnormality was detected: an intramedullary lesion consistent with a small cyst or syrinx. There were no statistically significant associations between the outcome of injury and spondylosis or loss of lordosis. No significant changes were found when comparing the initial and follow-up MRI. It appears that MRI of patients with relatively less severe whiplash symptoms reveals a low frequency of abnormalities, apart from spondylosis and loss of lordosis, which have little short-term prognostic value. Routine investigation of such patients with MRI is not justified in view of the infrequency of abnormalities detected, the lack of prognostic value and the high cost of the procedure.
Recruitment is a major challenge for many trials; just over half reach their targets and almost a third resort to grant extensions. The economic and societal implications of this shortcoming are ...significant. Yet, we have a limited understanding of the processes that increase the probability that recruitment targets will be achieved. Accordingly, there is an urgent need to bring analytical rigour to the task of improving recruitment, thereby increasing the likelihood that trials reach their recruitment targets. This paper presents a conceptual framework that can be used to improve recruitment to clinical trials.
Using a case-study approach, we reviewed the range of initiatives that had been undertaken to improve recruitment in the txt2stop trial using qualitative (semi-structured interviews with the principal investigator) and quantitative (recruitment) data analysis. Later, the txt2stop recruitment practices were compared to a previous model of marketing a trial and to key constructs in social marketing theory.
Post hoc, we developed a recruitment optimisation model to serve as a conceptual framework to improve recruitment to clinical trials. A core premise of the model is that improving recruitment needs to be an iterative, learning process. The model describes three essential activities: i) recruitment phase monitoring, ii) marketing research, and iii) the evaluation of current performance. We describe the initiatives undertaken by the txt2stop trial and the results achieved, as an example of the use of the model.
Further research should explore the impact of adopting the recruitment optimisation model when applied to other trials.
Background the UK Small Aneurysm Trial was established to test the benefit of prophylactic elective surgery for small abdominal aortic aneurysms (4.0–5.5 cm in diameter) and identify prognostic risk ...factors, including smoking. Patients, methods and outcomes one thousand and ninety patients (902 men and 188 women, mean age 69.3 years) were randomised to either early elective surgery or ultrasonography surveillance until the aneurysm diameter exceeded 5.5 cm, mean follow-up was 4.6 years. Baseline assessments included lung function tests and cotinine (a smoking marker). The principal outcome measures were all-cause mortality and aneurysm rupture. Results during the course of the trial, aneurysm rupture was diagnosed in 25 patients and 309 patients died. Whereas self-reported smoking status was not significantly associated with survival, patients without any trace of plasma cotinine had a significantly improved long-term (6-year) survival,p =0.02. Current smokers had a lower FEV1than past- and never-smokers. FEV1was the most powerful predictor of long-term (6-year) survival, the crude death rates per 100 person-years were 9.1, 6.9 and 4.6 for those with FEV1<1.9 l, 1.9–2.5 l and >2.5 l respectively, p=0.001. Moreover, the rupture rate was 1.9% per year for patients positive for plasma cotinine compared with 0.5% in those without trace of plasma cotinine,p =0.004. Conclusions self-reported smoking status underestimates the effect of continued smoking on the prognosis of patients with small abdominal aortic aneurysm. Patients with high plasma cotinine concentrations (smokers) have an increased risk of aneurysm rupture and poorer long-term survival.
To study the outcome of surgery versus ultrasound surveillance for small aortic aneurysms.
Multicentre, random allocation, open trial.
University and general hospitals across the UK.
Patients aged ...60–76 years with small asymptomatic abdominal aortic aneurysms (4–5.5 cm in diameter).
The mortality rate, costs, usage of health service resources and quality of life of each treatment will be compared.
From patients randomised to ultrasound surveillance, the natural history of small aneurysms will be determined. The design, methods and progress of this trial are reported here.
The T1-weighted magnetic resonance examinations in 11 acquired immunodeficiency syndrome patients showed substantial reduction in signal intensity of vertebral bodies. Review of bone marrow aspirates ...and biopsies that were available in eight patients suggested that the abnormality resulted from markedly increased amounts of storage iron within the bone marrow, probably secondary to the anemia of chronic disease.
To investigate factors associated with a prolonged hospital stay after elective open surgical repair of abdominal aortic aneurysm.
We have investigated prospectively base-line risk factors associated ...with an increased length of postoperative hospital stay in 474 of the patients undergoing surgery as part of the U.K. Small Aneurysm Trial.
The median length of hospital stay was 11 days (interquartile range 9–14 days). Age (within the range 60–76 years), sex, body mass index, aneurysm diameter, graft type (tube or bifurcated), hospital (university or other), ECG characteristics, angina (from Rose questionnaire) and/or previous myocardial infarction were not associated with length of hospital stay. Quality of life also was assessed before surgery using the Medical Outcomes Study SF20. Psychosocial aspects including level of social functioning, role functioning, mental health, health perceptions and pain were not associated with length of postoperative stay. The level of preoperative physical functioning was associated inversely with length of hospital stay,
p = 0.004. Patients' length of hospital stay also was inversely associated with preoperative lung function: FEV
1,
p = 0.011 and FVC,
p = 0.006. In contrast, smoking habit was of only borderline significance,
p = 0.09.
Conditional logistic regression analysis identified only preoperative lung function (FEV
1 and FVC) and physical functioning, three intrinsically linked factors, as predictors of length of hospital stay after elective repair of an abdominal aortic aneurysm.
In a consecutive series of 70 patients with carcinoma of the rectum, 42 had operable tumours and in these the histology of the initial biopsy was compared with that of the excised specimen. In 9 of ...the 42 patients the histological grading of the original biopsy was different from that of the final specimen; in 3 the carcinoma was missed despite repeated preoperative biopsies; and in 5, errors were made in the diagnosis of carcinoma in polyps. In 5 of 7 cases of poorly differentiated carcinoma the initial biopsies indicated moderate differentiation: there was therefore a 70% inaccuracy in the preoperative diagnosis of poorly differentiated carcinoma of the rectum. The implications of this inaccuracy for the surgery of rectal cancer are discussed.
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