A systematic assessment of the association between frequently prescribed medicines and the risk of common cancers: a series of nested case-control studies

BACKGROUND

Studies systematically screening medications have successfully identified prescription medicines associated with cancer risk. However, adjustment for confounding factors in these studies has been limited. We therefore investigated the association between frequently prescribed medicines and the risk of common cancers adjusting for a range of confounders.

METHODS

A series of nested case-control studies were undertaken using the Primary Care Clinical Informatics Unit Research (PCCIUR) database containing general practice (GP) records from Scotland. Cancer cases at 22 cancer sites, diagnosed between 1999 and 2011, were identified from GP records and matched with up to five controls (based on age, gender, GP practice and date of registration). Odds ratios (OR) and 95% confidence intervals (CI) comparing any versus no prescriptions for each of the most commonly prescribed medicines, identified from prescription records, were calculated using conditional logistic regression, adjusting for comorbidities. Additional analyses adjusted for smoking use. An association was considered a signal based upon the magnitude of its adjusted OR, p-value and evidence of an exposure-response relationship. Supplementary analyses were undertaken comparing 6 or more prescriptions versus less than 6 for each medicine.

RESULTS

Overall, 62,109 cases and 276,580 controls were included in the analyses and a total of 5622 medication-cancer associations were studied across the 22 cancer sites. After adjusting for comorbidities 2060 medicine-cancer associations for any prescription had adjusted ORs greater than 1.25 (or less than 0.8), 214 had a corresponding p-value less than or equal to 0.01 and 118 had evidence of an exposure-dose relationship hence meeting the criteria for a signal. Seventy-seven signals were identified after additionally adjusting for smoking. Based upon an exposure of 6 or more prescriptions, there were 118 signals after adjusting for comorbidities and 82 after additionally adjusting for smoking.

CONCLUSIONS

In this study a number of novel associations between medicine and cancer were identified which require further clinical and epidemiological investigation. The majority of medicines were not associated with an altered cancer risk and many identified signals reflected known associations between medicine and cancer.

THU0134 COGNITIVE IMPAIRMENT IN RHEUMATOID ARTHRITIS

Background:

Increasing evidence suggests that systemic inflammation may be associated with an increased risk of developing cognitive dysfunction and Alzheimer’s disease (AD). Some studies have found an association between rheumatoid arthritis (RA) and neurodegeneration with several finding increased incidence of mild cognitive impairment (MCI) in those with RA compared to healthy controls.

Objectives:

This study aims to use preliminary data from theRheumatoid arthritis, medication and memorystudy (RESIST) to investigate the prevalence of MCI in a population of patients with RA and explore the relationship between MCI and specific demographic and clinical characteristics.

Methods:

The Montreal Cognitive Assessment (MoCA) was used as a cognitive screening tool and was administered to subjects ≥55 years of age who had been diagnosed with RA according to the ACR/EULAR criteria. Demographic and clinical data was recorded at screening in face-to-face interviews and included age, gender, date of RA diagnosis and RA medication. RA disease activity score from 28 joints (DAS28), rheumatoid factor (RF) level, anti-cyclic citrullinated peptide (anti-CCP) level, erythrocyte sedimentation rate (ESR) were recorded. 260 participants completed both screening and baseline visits as part of the RESIST longitudinal study, MoCA scores from baseline were analysed for these participants. Statistical analysis was used to provide descriptive statistics and explore possible predictors of cognitive impairment.

Results:

A total of 636 participants (mean age 68.1 yrs, female 67.5%) were screened between May 2018 and December 2019. The mean MoCA for screened participants was 25.4; 45.3% scored <26 in the MoCA and were considered to have mild cognitive impairment. Age was negatively correlated with MoCA score and was the only significant predictor of cognitive impairment. For each year of increase in age the MoCA score reduced by a mean of 0.08 points (p<0.05). There was little evidence of a difference in mean MoCA score by gender, RA medication, duration of disease, DAS28 score, ESR, anti-CCP or RF levels. The mean MoCA scores increased by 0.4 points between screening and baseline (P<0.001).

Conclusion:

A large proportion of participants scored below the proposed cut-off for normal cognition in the MoCA suggesting a high prevalence of MCI in adults >55 years with moderately active RA. This provides further support for the role of chronic inflammation in cognitive dysfunction and AD. Screening for MCI in rheumatology clinics might be clinically useful.

DemographicsOutcomeAge mean years (+/-SD) (n=633)68.1 (8.01)Gender (n=636)Female n (%)429 (67.5)RA Medication (n=636)csDMARD n (%)TNFi n (%)368 (57.9)268 (42.1)Duration of RA mean years (+/-SD) (n=484)14.4 (13.9)DAS28 mean (+/-SD) (n=306)3.5 (2.04)ESR mean (+/-SD) (n=501)23.4 (22.0)Anti-CCP (n=387)Positive n (%)236 (61)Rheumatoid Factor (n=377)Positive n (%)277 (73.5)MoCA Score points (n=636)≥26, n (%)<26 n (%)348 (54.7)288 (45.3)Subjective memory concerns (n=430)Yes n (%)No n (%)95 (22.1)335 (77.9)

Disclosure of Interests:

Christopher Edwards Grant/research support from: Abbvie, Biogen, Roche, Consultant of: Abbvie, Samsung, Speakers bureau: Abbvie, BMS, Biogen, Celgene, Fresenius, Gilead, Janssen, Lilly, Mundipharma, Pfizer, MSD, Novartis, Roche, Samsung, Sanofi, UCB

, Bethany McDowell: None declared, Chris Holroyd: None declared, Chris Cardwell: None declared, Michelle McHenry Speakers bureau: Novartis, Pfizer, AbbVie, Celgene, Lilly, Gary Meenagh: None declared, Clive Holmes: None declared, Bernadette McGuiness: None declared

Dietary Patterns and Retinal Vessel Caliber in the Irish Nun Eye Study

BACKGROUND

Retinal vessel abnormalities are associated with cardiovascular disease risk. Widening of retinal venules is associated with increased risk of stroke while narrowing of retinal arterioles independently predicts incident hypertension, coronary heart disease and diabetes. Dietary factors are known to play an important role in cardiovascular health. However, few studies have examined the association between dietary patterns (DPs) and retinal microvascular health.

OBJECTIVE

To examine the association between 'a posteriori'-derived DPs and retinal vascular caliber (RVC) in older women with a restricted lifestyle.

METHODS

This was a cross-sectional study of 1233 participants (mean age: 76.3 years) from the Irish Nun Eye Study (INES). Computer-assisted software was used to measure RVC from digital eye images using standardized protocols. Dietary intake was assessed using a food frequency questionnaire (FFQ). DP analysis was performed using principal component analysis from completed FFQs. Regression models were used to assess associations between DPs and retinal vessel diameters, adjusting for age, body mass index, refraction, hypertension, diabetes mellitus, ischemic heart disease, cerebrovascular accident and fellow eye RVC.

RESULTS

Two DPs were identified: a 'healthy' pattern with high factor loadings for fruit, vegetables, wholegrains and oily fish and an 'unhealthy' pattern with high factor loadings for sugar and sweets, chips, high fat dairy products and French fries. Adjusted linear regression analysis revealed that those who adhered most closely to the unhealthy DP had wider central retinal venular equivalent (CRVE) (p=0.03) and narrower central retinal arteriolar equivalent (CRAE) (p=0.01) compared to the least unhealthy DP. No independent relationship was observed between the healthy DP and RVC.

CONCLUSION

In this cohort of older women with a restricted lifestyle, an unhealthy DP was independently associated with an unfavorable retinal profile, namely a widening of retinal venules and narrowing of retinal arterioles.

β-Defensin 1 plays a role in acute mucosal defense against Candida albicans

Candida is an opportunistic fungal pathogen that colonizes the mucosal tract of humans. Pathogenic infection occurs in the presence of conditions causing perturbations to the commensal microbiota or host immunity. Early innate immune responses by the epithelium, including antimicrobial peptides (AMPs) and cytokines, are critical for protection against overgrowth. Reduced salivary AMP levels are associated with oral Candida infection, and certain AMPs, including human β-defensins 1-3, have direct fungicidal activity. In this study, we demonstrate that murine β-defensin 1 (mBD1) is important for control of early mucosal Candida infection and plays a critical role in the induction of innate inflammatory mediators. Mice deficient in mBD1, as compared with wild-type mice, exhibit elevated oral and systemic fungal burdens. Neutrophil infiltration to the sites of mucosal Candida invasion, an important step in limiting fungal infection, is significantly reduced in mBD1-deficient mice. These mice also exhibit defects in the expression of other AMPs, including mBD2 and mBD4, which may have direct anti-Candida activity. We also show that mBD1 deficiency impacts the production of important antifungal inflammatory mediators, including IL-1β, IL-6, KC, and IL-17. Collectively, these studies demonstrate a role for the mBD1 peptide in early control of Candida infection in a murine model of mucosal candidiasis, as well as in the modulation of host immunity through augmentation of leukocyte infiltration and inflammatory gene regulation.

Increase in the pharmacological management of Type 2 diabetes with pay-for-performance in primary care in the UK

AIMS

To determine whether the financial incentives for tight glycaemic control, introduced in the UK as part of a pay-for-performance scheme in 2004, increased the rate at which people with newly diagnosed Type 2 diabetes were started on anti-diabetic medication.

METHODS

A secondary analysis of data from the General Practice Research Database for the years 1999-2008 was performed using an interrupted time series analysis of the treatment patterns for people newly diagnosed with Type 2 diabetes (n = 21 197).

RESULTS

Overall, the proportion of people with newly diagnosed diabetes managed without medication 12 months after diagnosis was 47% and after 24 months it was 40%. The annual rate of initiation of pharmacological treatment within 12 months of diagnosis was decreasing before the introduction of the pay-for-performance scheme by 1.2% per year (95% CI -2.0, -0.5%) and increased after the introduction of the scheme by 1.9% per year (95% CI 1.1, 2.7%). The equivalent figures for treatment within 24 months of diagnosis were -1.4% (95% CI -2.1, -0.8%) before the scheme was introduced and 1.6% (95% CI 0.8, 2.3%) after the scheme was introduced.

CONCLUSION

The present study suggests that the introduction of financial incentives in 2004 has effected a change in the management of people newly diagnosed with diabetes. We conclude that a greater proportion of people with newly diagnosed diabetes are being initiated on medication within 1 and 2 years of diagnosis as a result of the introduction of financial incentives for tight glycaemic control.

Characterization and functional analysis of cellular immunity in mice with biotinidase deficiency

Biotinidase deficiency is an autosomal recessively inherited metabolic disorder that can be easily and effectively treated with pharmacological doses of the vitamin, biotin. Untreated children with profound biotinidase deficiency may exhibit neurological, cutaneous and cellular immunological abnormalities, specifically candida infections. To better understand the immunological dysfunction in some symptomatic individuals with biotinidase deficiency, we studied various aspects of immunological function in a genetically engineered knock-out mouse with biotinidase deficiency. The mouse has no detectable biotinidase activity and develops neurological and cutaneous symptoms similar to those seen in symptomatic children with the disorder. Mice with profound biotinidase deficiency on a biotin-restricted diet had smaller thymuses and spleens than identical mice fed a biotin-replete diet or wildtype mice on either diet; however, the organ to body weight ratios were not significantly different. Thymus histology was normal. Splenocyte subpopulation study showed a significant increase in CD4 positive cells. In addition, in vitro lymphocyte proliferation assays consistently showed diminished proliferation in response to various immunological stimuli. Not all symptomatic individuals with profound biotinidase deficiency develop immunological dysfunction; however, our results do show significant alterations in cellular immunological function that may contribute and/or provide a mechanism(s) for the cellular immunity abnormalities in individuals with biotinidase deficiency.

Inflammatory and immunological biomarkers are not related to survival in adults with Cystic Fibrosis

BACKGROUND

Chronic Pseudomonas aeruginosa pulmonary infection is associated with a decline in lung function and reduced survival in people with Cystic Fibrosis (CF). Damaging inflammatory and immunological mediators released in the lungs can be used as markers of chronic infection, inflammation and lung tissue damage.

METHODS

Clinical samples were collected from CF patients and healthy controls. Serum IgG and IgA anti-Pseudomonas antibodies, sputum IL-8 and TNFα, plasma IL-6 and urine TNFr1 were measured by ELISA. Sputum neutrophil elastase (NE), cathepsin S and cathepsin B were measured by spectrophotometric and fluorogenic assays. The relationship between IgG and IgA, inflammatory mediators and long-term survival was determined.

RESULTS

IgG and IL-6 positively correlated with mortality. However, multivariate analysis demonstrated that after adjusting for FEV(1), IgG was not independently related to mortality. A relationship was observed between IgG and IL-6, TNFα, TNFr1 and between IgA and IL8, cathepsin S and cathepsin B.

CONCLUSIONS

These data indicate that biomarkers of inflammation are not independent predictors of survival in people with CF.

Isolation and screening of carboxydotrophs isolated from composts and their potential for butanol synthesis

Carboxydotrophs are known for their ability to convert carbon monoxide (CO) to butanol through fermentation. Such a platform offers a promising alternative approach to biofuel production from synthesis gas feedstocks. In this study, carboxydotrophs were isolated from various manure compost. Out of 500 isolates, only 11 carboxydotrophs (7 mesophiles and 4 thermophiles) were found to utilize CO as the sole source of carbon and energy. To assess the biochemical basis for their ability to produce biofuel (butanol), the level of activities of CO dehydrogenase (CODH), hydrogenase and butanol dehydrogenase (BDH) enzymes for these isolates against the known carboxydotroph, Butyribacterium methylotrophicum was assessed. All isolates showed evidence of enzyme activities (0.16-2.20 micromol min(-1)), with the majority exhibiting higher activities compared with the known carboxydotroph, B. methylotrophicum (0.33-0.71 micromol min(-1)). The level of activities for CODH and BDH ranged from 0.163-3.59 micromolmin(-1) and 0.19-2.2 micromolmin(-1), respectively. Three isolates (M7-1, T2-22, and T3-14) demonstrated enzymatic activity three to seven times higher than B. methylotrophicum. Of these, T2-22 exhibited the highest BDH activity and shows great promise in the conversion of toxic CO into butanol more so than other carboxytotrophs known thus far. This study revealed some biochemical basis for butanol production from CO by carboxydotrophs. However, more research is needed to discover a direct biological route for butanol production from CO to strengthen their potential for synthesis gas bioprocessing. Follow-up work will focus on whole-genome sequencing of the promising isolate T2-22 to provide system-level insights into how carboxydotrophs utilize and regulate their molecular machineries for butanol production.

Neurological deficits in mice with profound biotinidase deficiency are associated with demylination and axonal degeneration

Biotinidase deficiency is an autosomal recessively inherited disorder characterized by neurological and cutaneous abnormalities. We have developed a transgenic knock-out mouse with biotinidase deficiency to better understand aspects of pathophysiology and natural history of the disorder in humans. Neurological deficits observed in symptomatic mice with biotinidase deficiency are similar to those seen in symptomatic children with the disorder. Using a battery of functional neurological assessment tests, the symptomatic mice performed poorly compared to wild-type mice. Demyelination, axonal degeneration, ventriculomegaly, and corpus callosum compression were found in the brains of untreated, symptomatic enzyme-deficient mice. With biotin treatment, the symptomatic mice improved neurologically and the white matter abnormalities resolved. These functional and anatomical findings and their reversal with biotin therapy are similar to those observed in untreated, symptomatic and treated individuals with biotinidase deficiency. The mouse with biotinidase deficiency appears to be an appropriate animal model in which to study the neurological abnormalities and the effects of treatment of the disorder.

Use of culture and molecular analysis to determine the effect of antibiotic treatment on microbial community diversity and abundance during exacerbation in patients with cystic fibrosis

BACKGROUND

Anaerobic bacteria are increasingly regarded as important in cystic fibrosis (CF) pulmonary infection. The aim of this study was to determine the effect of antibiotic treatment on aerobic and anaerobic microbial community diversity and abundance during exacerbations in patients with CF.

METHODS

Sputum was collected at the start and completion of antibiotic treatment of exacerbations and when clinically stable. Bacteria were quantified and identified following culture, and community composition was also examined using culture-independent methods.

RESULTS

Pseudomonas aeruginosa or Burkholderia cepacia complex were detected by culture in 24/26 samples at the start of treatment, 22/26 samples at completion of treatment and 11/13 stable samples. Anaerobic bacteria were detected in all start of treatment and stable samples and in 23/26 completion of treatment samples. Molecular analysis showed greater bacterial diversity within sputum samples than was detected by culture; there was reasonably good agreement between the methods for the presence or absence of aerobic bacteria such as P aeruginosa (κ=0.74) and B cepacia complex (κ=0.92), but agreement was poorer for anaerobes. Both methods showed that the composition of the bacterial community varied between patients but remained relatively stable in most individuals despite treatment. Bacterial abundance decreased transiently following treatment, with this effect more evident for aerobes (median decrease in total viable count 2.3×10(7) cfu/g, p=0.005) than for anaerobes (median decrease in total viable count 3×10(6) cfu/g, p=0.046).

CONCLUSION

Antibiotic treatment targeted against aerobes had a minimal effect on abundance of anaerobes and community composition, with both culture and molecular detection methods required for comprehensive characterisation of the microbial community in the CF lung. Further studies are required to determine the clinical significance of and optimal treatment for these newly identified bacteria.

The epidemiology of red cell transfusion

BACKGROUND AND OBJECTIVES

Understanding of the clinical usage of red cells is limited despite its importance in transfusion practice improvement and planning for blood supply requirements. Previous studies have described red cell use based upon ICD and hospital discharge codes; however, such approaches are open to misclassification. This study addresses this limitation by undertaking an epidemiological analysis of red cell use using case note review.

MATERIALS AND METHODS

Patient, disease and contextual factors were extracted from the medical records of a randomly selected sample of hospital patients in Northern Ireland who received a red cell transfusion during 2005 (n=1474).

RESULTS

Transfused patients received a total of 3804 units (median of two units per transfusion episode). Most transfusions occurred in a medical setting (71%). Patients undergoing treatment for gastrointestinal conditions were responsible for the majority of the demand (29% of transfusion episodes; 34% of red cell units). The presence of bleeding and abnormal tests of coagulation were associated with receiving larger transfusions (≥ 3 units), while patients undergoing orthopaedic surgery and those with a haemoglobin level over 7 g/dl had the lowest risk of receiving ≥ 3 units in any one transfusion episode.

CONCLUSION

The majority of red cells are now prescribed in a medical setting. With an ageing population and increasing therapeutic interventions, the demand for blood is likely to increase despite efforts to reduce usage by eliminating inappropriate transfusions through education and behaviour change. The post-transfusion target (and therefore the number of units to transfuse) for any given clinical situation as well as guidance on a 'safe' transfusion threshold should be considered in future guidelines.

Meta-analysis of the effects of lithium usage on serum creatinine levels

There is conflicting evidence concerning lithium's effect on renal function. The aim is to clarify whether lithium affects kidney function and at what stage of treatment any effect may occur. Systematic review identified 23 studies split into three groups on which meta-analysis was performed to identify the following: A) lithium's effect on renal function in cross-sectional case-control studies, B) studies of renal function before and after commencement on lithium, C) studies of longer term effect in those already established on lithium therapy. Group A showed a statistically significant increase of 5.7 μmol/L in creatinine in the study population compared with controls. Group B showed a non-statistically significant rise in creatinine (2.9 μmol/L) after a mean follow-up of 86 months. Group C showed a statistically significant increase in creatinine of 7.0 μmol/L over a mean duration of 64 months. An increase in creatinine of an average of 1.6 μmol/L/year on lithium was also identified in this group. Any lithium-associated increase in serum creatinine is quantitatively small and of questionable clinical significance. However, routine renal function monitoring of patients on lithium is essential.

Cluster randomised controlled trial of an infection control education and training intervention programme focusing on meticillin-resistant Staphylococcus aureus in nursing homes for older people

The aim of this cluster randomised controlled trial was to test the impact of an infection control education and training programme on meticillin-resistant Staphylococcus aureus (MRSA) prevalence in nursing homes. Nursing homes were randomised to intervention (infection control education and training programme; N=16) or control (usual practice continued; N=16). Staff in intervention homes were educated and trained (0, 3 and 6 months) in the principles and implementation of good infection control practice with infection control audits conducted in all sites (0, 3, 6 and 12 months) to assess compliance with good practice. Audit scores were fed back to nursing home managers in intervention homes, together with a written report indicating where practice could be improved. Nasal swabs were taken from all consenting residents and staff at 0, 3, 6 and 12 months. The primary outcome was MRSA prevalence in residents and staff, and the secondary outcome was a change in infection control audit scores. In all, 793 residents and 338 staff were recruited at baseline. MRSA prevalence did not change during the study in residents or staff. The relative risk of a resident being colonised with MRSA in an intervention home compared with a control home at 12 months was 0.99 (95% confidence interval: 0.69, 1.42) after adjustment for clustering. Mean infection control audit scores were significantly higher in the intervention homes (82%) compared with the control homes (64%) at 12 months (P<0.0001). Consideration should be given to other approaches which may help to reduce MRSA in this setting.

Lignans and breast cancer risk in pre- and post-menopausal women: meta-analyses of observational studies

Phyto-oestrogens are plant compounds structurally similar to oestradiol, which have been proposed to have protective effects against breast cancer. The main class of phyto-oestrogens in the Western diet is lignans. Literature reports on the effect of lignans in breast cancer risk have been conflicting. We performed three separate meta-analyses to examine the relationships between (i) plant lignan intake, (ii) enterolignan exposure and (iii) blood enterolactone levels and breast cancer risk. Medline, BIOSIS and EMBASE databases were searched for publications up to 30 September 2008, and 23 studies were included in the random effects meta-analyses. Overall, there was little association between high plant lignan intake and breast cancer risk (11 studies, combined odds ratio (OR): 0.93, 95% confidence interval (95% CI): 0.83-1.03, P=0.15), but this association was subjected to marked heterogeneity (I(2)=44%). Restricting the analysis to post-menopausal women, high levels of plant lignan intake were associated with reduced breast cancer risk (7 studies, combined OR: 0.85, 95% CI: 0.78, 0.93, P<0.001) and heterogeneity was markedly reduced (I(2)=0%). High enterolignan exposure was also associated with breast cancer (5 studies, combined OR: 0.73, 95% CI: 0.57, 0.92, P=0.009) but, again, there was marked heterogeneity (I(2)=63%). No association was found with blood enterolactone levels (combined OR: 0.82, 95% CI: 0.59-1.14, P=0.24). In conclusion, plant lignans may be associated with a small reduction in post-menopausal breast cancer risk, but further studies are required to confirm these results.

Influence of prolonged hospitalization on overall bed occupancy: a five-year single-centre study

BACKGROUND

Effective bed use is crucial to an efficient NHS. Current targets suggest a decrease in mean occupancy as the most appropriate method of improving overall efficiency. The elderly and those suffering from complex medical problems are thought to account for a high proportion of overall bed occupancy.

AIM

To assess the effect of prolonged hospital stay (>100 days) on overall bed occupancy in a modern teaching hospital.

DESIGN

Retrospective analysis.

METHODS

Analysis of all admission episodes (n = 117,178) over a five-year period in a large teaching hospital in a single UK region, serving a population of approximately 200,000. A logistic regression multi-factorial model was used to assess the effect of demographic and diagnostic variables on duration of stay.

RESULTS

A prolonged stay (>100 days) was seen in 648 admission episodes (0.6%). These accounted for 11% of the overall bed occupancy over the 5-year period. Excluding all prolonged admission episodes from our analysis made no difference to the overall median length of stay.

DISCUSSION

Prolonged hospitalizations have a significant impact on bed occupancy. Targeting these very long (>100 days) hospital stays may better improve overall efficiency, compared to targeting mean or median length of stay.

Endovascular treatment for ruptured abdominal aortic aneurysm

BACKGROUND

An abdominal aortic aneurysm (AAA) (the pathological enlargement of the aorta) can develop in both men and women as they grow older. It is most commonly seen in men over the age of 65 years. Progressive aneurysm enlargement can lead to rupture and massive internal bleeding, a fatal event unless timely repair can be achieved. Despite improvements in perioperative care, mortality remains high (approximately 50%) after conventional open surgical repair. A newer minimally invasive technique, endovascular repair, has been shown to reduce early morbidity and mortality, as compared to conventional open surgery, for planned AAA repair. Emergency endovascular repair (eEVAR) has been used successfully to treat ruptured abdominal aortic aneurysm (RAAA), proving that it is feasible in selected patients. However, it is not yet known if eEVAR will lead to significant improvements in outcomes for these patients or indeed if it can replace conventional open repair as the preferred treatment for this lethal condition.

OBJECTIVES

To compare the advantages and disadvantages of eEVAR in comparison with conventional open surgical repair for the treatment of RAAA.

SEARCH STRATEGY

The Cochrane Peripheral Vascular Diseases Group searched their trials register (last searched October 2006) and the Cochrane Central Register of Controlled Trials (CENTRAL) database (last searched Issue 4, 2006). We searched a number of electronic databases and handsearched relevant journals until March 2006 to identify studies for inclusion.

SELECTION CRITERIA

Randomised controlled trials in which patients with a confirmed ruptured abdominal aortic aneurysm were randomly allocated to eEVAR, or conventional open surgical repair.

DATA COLLECTION AND ANALYSIS

Studies identified for potential inclusion were independently assessed for eligibility by at least two reviewers, with excluded studies further checked by the agreed arbitrators. As no randomised controlled trials were identified at present no tests of heterogeneity or sensitivity analysis were performed.

MAIN RESULTS

There were no randomised controlled trials identified at present comparing eEVAR with conventional open surgical repair for the treatment of RAAA.

AUTHORS' CONCLUSIONS

There is no high quality evidence to support the use of eEVAR in the treatment of RAAA. However, evidence from prospective controlled studies without randomisation, prospective studies, and retrospective case series suggest that eEVAR is feasible in selected patients, with outcomes comparable to best conventional open surgical repair for the treatment of RAAA . Furthermore, endovascular repair in selected patients may be associated with a trend towards reductions in blood loss, duration of intensive care treatment, and mortality.

Secular trends in heart rate in young adults, 1949 to 2004: analyses of cross sectional studies

OBJECTIVE

To investigate secular trends in resting heart rate in young adults.

DESIGN, SETTING, AND PARTICIPANTS

A series of cross sectional cohorts of first year undergraduates (5562) aged 16-24 years who attended Queen's University Belfast from 1949 to 2004 and underwent health checks at the university health centre.

MAIN OUTCOME MEASURE

Resting heart rate.

RESULTS

Crude aggregate data for 1949-59 showed a secular decline in heart rate in male and female students. Both unadjusted and fully adjusted analyses of data from 1975 onwards-controlled for age, body mass index, height, and smoking-showed a U shaped association between heart rate and year of entry to university in both sexes (p < 0.001): heart rate initially declined and then increased from the mid 1980s. Trends were similar in smokers and non-smokers and in students with normal body size and those who were overweight. However, heart rate in the 693 (28%) male students reporting the most physical activity remained stable and lower than that of men who participated in less physical activity over the period of the study. Similarly in female students, heart rate was generally lower in the 210 (10%) who participated in the most physical activity than in those who engaged in less physical activity.

CONCLUSIONS

The decline in heart rate in young adults occurring at least 50 years ago and continuing until the 1980s is consistent with other favourable findings on cardiovascular health in this age group and with observed long term declines in cardiovascular mortality. The more recent rise in heart rate, not accounted for by increases in overweight, prompts concern that recent favourable trends in cardiovascular disease risk may not be maintained. Among students who took part in the highest levels of physical activity the finding of low and stable heart rates points to the importance of exercise in maintaining cardiovascular health. Measurement of heart rate in population surveys would provide a simple tool to assist monitoring cardiovascular health.

Observer Variation in the Detection of Colorectal Neoplasia on Double-contrast Barium Enema: Implications for Colorectal Cancer Screening and Training

AIM

To assess inter-observer error for the diagnosis of neoplasia on double contrast barium enema (DCBE) in the light of claims that no additional interpretative training would be needed for implementation in a national screening programme.

MATERIALS AND METHODS

10 experts, 10 consultants, and 10 experienced trainees each reported 20 DCBE studies, of which two showed cancer, three showed large polyps, four showed small polyps, and 12 were normal. Inter-observer variation was compared using odds ratios with the trainee group as reference (baseline group).

RESULTS

Experts were significantly more likely to correctly identify neoplasia on DCBE than trainees. The odds of a correct diagnosis for experts were 2.79 (95% CI 2.04, 3.81) for cancer, 2.36 (1.88, 2.97) for large polyps, and 3.50 (1.98, 6.18) for small polyps. While consultants were more likely to correctly diagnose a large polyp than trainees, 1.45 (1.15, 1.84), there was no significant difference between these two groups for the correct diagnosis of either cancer, 1.24 (0.52, 2.96), or small polyps, 1.26 (0.83, 1.90). A cancer was missed by 6 (60%) experts, 9 (90%) consultants, and 8 (80%) trainees. Large polyps were missed by 4 (40%) experts, 5 (50%) consultants, and 6 (60%) trainees. There was no significant difference between any group when false positive diagnoses were considered.

CONCLUSIONS

There is considerable inter-observer perceptive error for the diagnosis of neoplasia on DCBE. Experts performed significantly better than other observers but the overall standard of performance was poor, even amongst experts.

Helping health professionals deal with violence

Violence towards health professionals is defined as any incident in which a health professional experiences abuse, threat, fear or the application of force arising out of the course of his or her work, whether or not they are on duty. It emerges that no single theory can adequately explain the phenomenon, and perceptions about incidence and prevalence are distorted by the media. There is consistent and variable reporting but a high incidence and prevalence undoubtedly exists within health care. Health professionals and less experienced nurses in particular have been found to be most at risk. A strategic approach is needed to the development and implementation of workplace-specific solutions. Health professionals have a right to expect that violence at work is minimized but it would be unrealistic to expect it to be eradicated.

A novel type of programmed neuronal death in the cervical spinal cord of the chick embryo

We examined the massive early cell death that occurs in the ventral horn of the cervical spinal cord of the chick embryo between embryonic days 4 and 5 (E4 and E5). Studies with immunohistochemical, in situ hybridization, and retrograde-tracing methods revealed that many dying cells express Islet proteins and Lim-3 mRNA (motoneuron markers) and send their axons to the somatic region of the embryo before cell death. Together, these data strongly suggest that the dying cells are somatic motoneurons. Cervical motoneurons die by apoptosis and can be rescued by treatment with cycloheximide and actinomycin D. Counts by motoneuron numbers between E3.5 and E10 revealed that, in addition to cell death between E4 and E5, motoneuron death also occur between E6 and E10 in the cervical cord. Studies with [3H]thymidine autoradiography and morphological techniques revealed that in the early cell-death phase (E4-E5), genesis of motoneurons, axonal elongation, and innervation of muscles is still ongoing. However, studies with [3H]thymidine autoradiography also revealed that the cells dying between E4 and E5 become postmitotic before E3.5. Increased size of peripheral targets, treatment with neuromuscular blockade, and treatment with partially purified muscle or brain extracts and defined neurotropic agents, such as NGF, BDNF, neurotrophin-3, CNTF, bFGF, PDGF, S100-beta, activin, cholinergic differentiation factor/leukemia inhibitory factor, bone morphogenetic protein-2, IGF-I, interleukin-6, and TGF-beta 1, were all ineffective in rescuing motoneurons dying between E4 and E5. By contrast, motoneurons that undergo programmed cell death at later stages (E6-E10) in the cervical cord are target-dependent and respond to activity blockade and trophic factors. Experimental approaches revealed that early cell death also occurs in a notochord-induced ectopic supernumerary motoneuron column in the cervical cord. Transplantation of the cervical neural tube to other segmental regions failed to alter the early death of motoneurons, whereas transplantation of other segments to the cervical region failed to induce early motoneuron death. These results suggest that the mechanisms that regulate motoneuron death in the cervical spinal cord between E4 and E5 are independent of interactions with targets. Rather, this novel type of cell death seems to be determined by signals that either are cell-autonomous or are derived from other cells within the cervical neural tube.

Caffeine withdrawal symptoms and rate of metabolism

Forty normal subjects (mean age 36) had their caffeine intake estimated by keeping a diary (n=40) and also by analysing provided samples of tea and coffee (n=28). A test dose of caffeine (500 mg) was given and a series of salivary samples analysed to estimate pharmacokinetic measures of the rate of caffeine metabolism. They then underwent 48 h of placebo substitution using double-blind procedures. A wide range of physiological, psychological and subjective measures were taken on successive days during withdrawal and resumption of caffeine. On withdrawal, 27 subjects reported tiredness and 18 developed headache. Electroencephalograph, skin conductance and blood pressure changes were apparent. Sleep improved on withdrawal but subjects reported feeling less alert and more tired. The higher the usual caffeine intake, the greater the unpleasant feelings on withdrawal and the more marked the reversal of feelings on resumption. The faster the metabolism of caffeine, the less the drop in anxiety during withdrawal and the less its return on resumption. These correlations were, however, rather weak and sporadic.

Peptide inhibitors of the ICE protease family arrest programmed cell death of motoneurons in vivo and in vitro

Members of the CED-3/interleukin-1 beta-converting enzyme (ICE) protease family have been implicated in cell death in both invertebrates and vertebrates. In this report, we show that peptide inhibitors of ICE arrest the programmed cell death of motoneurons in vitro as a result of trophic factor deprivation and in vivo during the period of naturally occurring cell death. In addition, interdigital cells that die during development are also rescued in animals treated with ICE inhibitors. Taken together, these results provide the first evidence that ICE or an ICE-like protease plays a regulatory role not only in vertebrate motoneuron death but also in the developmentally regulated deaths of other cells in vivo.