Meta-analysis of 74,046 individuals identifies 11 new susceptibility loci for Alzheimer's disease

Eleven susceptibility loci for late-onset Alzheimer's disease (LOAD) were identified by previous studies; however, a large portion of the genetic risk for this disease remains unexplained. We conducted a large, two-stage meta-analysis of genome-wide association studies (GWAS) in individuals of European ancestry. In stage 1, we used genotyped and imputed data (7,055,881 SNPs) to perform meta-analysis on 4 previously published GWAS data sets consisting of 17,008 Alzheimer's disease cases and 37,154 controls. In stage 2, 11,632 SNPs were genotyped and tested for association in an independent set of 8,572 Alzheimer's disease cases and 11,312 controls. In addition to the APOE locus (encoding apolipoprotein E), 19 loci reached genome-wide significance (P < 5 × 10(-8)) in the combined stage 1 and stage 2 analysis, of which 11 are newly associated with Alzheimer's disease.

Genome-wide association study of CSF biomarkers Abeta1-42, t-tau, and p-tau181p in the ADNI cohort

OBJECTIVES

CSF levels of Aβ1-42, t-tau, and p-tau181p are potential early diagnostic markers for probable Alzheimer disease (AD). The influence of genetic variation on these markers has been investigated for candidate genes but not on a genome-wide basis. We report a genome-wide association study (GWAS) of CSF biomarkers (Aβ1-42, t-tau, p-tau181p, p-tau181p/Aβ1-42, and t-tau/Aβ1-42).

METHODS

A total of 374 non-Hispanic Caucasian participants in the Alzheimer's Disease Neuroimaging Initiative cohort with quality-controlled CSF and genotype data were included in this analysis. The main effect of single nucleotide polymorphisms (SNPs) under an additive genetic model was assessed on each of 5 CSF biomarkers. The p values of all SNPs for each CSF biomarker were adjusted for multiple comparisons by the Bonferroni method. We focused on SNPs with corrected p<0.01 (uncorrected p<3.10×10(-8)) and secondarily examined SNPs with uncorrected p values less than 10(-5) to identify potential candidates.

RESULTS

Four SNPs in the regions of the APOE, LOC100129500, TOMM40, and EPC2 genes reached genome-wide significance for associations with one or more CSF biomarkers. SNPs in CCDC134, ABCG2, SREBF2, and NFATC4, although not reaching genome-wide significance, were identified as potential candidates.

CONCLUSIONS

In addition to known candidate genes, APOE, TOMM40, and one hypothetical gene LOC100129500 partially overlapping APOE; one novel gene, EPC2, and several other interesting genes were associated with CSF biomarkers that are related to AD. These findings, especially the new EPC2 results, require replication in independent cohorts.

Management of frozen shoulder: a systematic review and cost-effectiveness analysis

BACKGROUND

Frozen shoulder is condition in which movement of the shoulder becomes restricted. It can be described as either primary (idiopathic) whereby the aetiology is unknown, or secondary, when it can be attributed to another cause. It is commonly a self-limiting condition, of approximately 1 to 3 years' duration, though incomplete resolution can occur.

OBJECTIVES

To evaluate the clinical effectiveness and cost-effectiveness of treatments for primary frozen shoulder, identify the most appropriate intervention by stage of condition and highlight any gaps in the evidence.

DATA SOURCES

A systematic review was conducted. Nineteen databases and other sources including the Cumulative Index to Nursing and Allied Health (CINAHL), Science Citation Index, BIOSIS Previews and Database of Abstracts of Reviews of Effects (DARE) were searched up to March 2010 and EMBASE and MEDLINE up to January 2011, without language restrictions. MEDLINE, CINAHL and PsycINFO were searched in June 2010 for studies of patients' views about treatment.

REVIEW METHODS

Randomised controlled trials (RCTs) evaluating physical therapies, arthrographic distension, steroid injection, sodium hyaluronate injection, manipulation under anaesthesia, capsular release or watchful waiting, alone or in combination were eligible for inclusion. Patients with primary frozen shoulder (with or without diabetes) were included. Quasi-experimental studies were included in the absence of RCTs and case series for manipulation under anaesthesia (MUA) and capsular release only. Full economic evaluations meeting the intervention and population inclusion criteria of the clinical review were included. Two researchers independently screened studies for relevance based on the inclusion criteria. One reviewer extracted data and assessed study quality; this was checked by a second reviewer. The main outcomes of interest were pain, range of movement, function and disability, quality of life and adverse events. The analysis comprised a narrative synthesis and pair-wise meta-analysis. A mixed-treatment comparison (MTC) was also undertaken. An economic decision model was intended, but was found to be implausible because of a lack of available evidence. Resource use was estimated from clinical advisors and combined with quality-adjusted life-years obtained through mapping to present tentative cost-effectiveness results.

RESULTS

Thirty-one clinical effectiveness studies and one economic evaluation were included. The clinical effectiveness studies evaluated steroid injection, sodium hyaluronate, supervised neglect, physical therapy (mainly physiotherapy), acupuncture, MUA, distension and capsular release. Many of the studies identified were at high risk of bias. Because of variation in the interventions and comparators few studies could be pooled in a meta-analysis. Based on single RCTs, and for some outcomes only, short-wave diathermy may be more effective than home exercise. High-grade mobilisation may be more effective than low-grade mobilisation in a population in which most patients have already had treatment. Data from two RCTs showed that there may be benefit from adding a single intra-articular steroid injection to home exercise in patients with frozen shoulder of < 6 months' duration. The same two trials showed that there may be benefit from adding physiotherapy (including mobilisation) to a single steroid injection. Based on a network of nine studies the MTC found that steroid combined with physiotherapy was the only treatment showing a statistically and clinically significant beneficial treatment effect compared with placebo for short-term pain (standardised mean difference -1.58, 95% credible interval -2.96 to -0.42). This analysis was based on only a subset of the evidence, which may explain why the findings are only partly supportive of the main analysis. No studies of patients' views about the treatments were identified. Average costs ranged from £36.16 for unguided steroid injections to £2204 for capsular release. The findings of the mapping suggest a positive relationship between outcome and European Quality of Life-5 Dimensions (EQ-5D) score: a decreasing visual analogue scale score (less pain) was accompanied by an increasing (better) EQ-5D score. The one published economic evaluation suggested that low-grade mobilisation may be more cost-effective than high-grade mobilisation. Our tentative cost-effectiveness analysis suggested that steroid alone may be more cost-effective than steroid plus physiotherapy or physiotherapy alone. These results are very uncertain.

LIMITATIONS

The key limitation was the lack of data available. It was not possible to undertake the planned synthesis exploring the influence of stage of frozen shoulder or the presence of diabetes on treatment effect. As a result of study diversity and poor reporting of outcome data there were few instances where the planned quantitative synthesis was possible or appropriate. Most of the included studies had a small number of participants and may have been underpowered. The lack of available data made the development of a decision-analytic model implausible. We found little evidence on treatment related to stage of condition, treatment pathways, the impact on quality of life, associated resource use and no information on utilities. Without making a number of questionable assumptions modelling was not possible.

CONCLUSIONS

There was limited clinical evidence on the effectiveness of treatments for primary frozen shoulder. The economic evidence was so limited that no conclusions can be made about the cost-effectiveness of the different treatments. High-quality primary research is required.

Enrichment of cis-regulatory gene expression SNPs and methylation quantitative trait loci among bipolar disorder susceptibility variants

We conducted a systematic study of top susceptibility variants from a genome-wide association (GWA) study of bipolar disorder to gain insight into the functional consequences of genetic variation influencing disease risk. We report here the results of experiments to explore the effects of these susceptibility variants on DNA methylation and mRNA expression in human cerebellum samples. Among the top susceptibility variants, we identified an enrichment of cis regulatory loci on mRNA expression (eQTLs), and a significant excess of quantitative trait loci for DNA CpG methylation, hereafter referred to as methylation quantitative trait loci (mQTLs). Bipolar disorder susceptibility variants that cis regulate both cerebellar expression and methylation of the same gene are a very small proportion of bipolar disorder susceptibility variants. This finding suggests that mQTLs and eQTLs provide orthogonal ways of functionally annotating genetic variation within the context of studies of pathophysiology in brain. No lymphocyte mQTL enrichment was found, suggesting that mQTL enrichment was specific to the cerebellum, in contrast to eQTLs. Separately, we found that using mQTL information to restrict the number of single-nucleotide polymorphisms studied enhances our ability to detect a significant association. With this restriction a priori informed by the observed functional enrichment, we identified a significant association (rs12618769, P(bonferroni)<0.05) from two other GWA studies (TGen+GAIN; 2191 cases and 1434 controls) of bipolar disorder, which we replicated in an independent GWA study (WTCCC). Collectively, our findings highlight the importance of integrating functional annotation of genetic variants for gene expression and DNA methylation to advance the biological understanding of bipolar disorder.

Breastfeeding promotion for infants in neonatal units: a systematic review and economic analysis

OBJECTIVES

To evaluate the effectiveness and cost-effectiveness of interventions that promote or inhibit breastfeeding or feeding with breastmilk for infants admitted to neonatal units, and to identify an agenda for future research.

DATA SOURCES

Electronic databases were searched (including MEDLINE and MEDLINE In-Process Citations, EMBASE, CINAHL, Maternity and Infant Care, PsycINFO, British Nursing Index and Archive, Health Management Information Consortium, Cochrane Central Register of Controlled Trials, Science Citation Index, Pascal, Latin American and Caribbean Health Sciences, MetaRegister of Controlled Trials, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effectiveness, Health Technology Assessment Database, National Research Register) from inception to February 2008. Advisors identified further published or unpublished material.

REVIEW METHODS

All papers fulfilled eligibility criteria covering participants, interventions, study design and outcomes. Results from primary studies were assessed and summarised in a qualitative synthesis for each type of intervention and across types of intervention. To estimate long-term cost utility, a decision tree was developed to synthesise data on enhanced staff contact, breastmilk effectiveness, incidence of necrotising enterocolitis (NEC) and sepsis, resource use, survival and utilities.

RESULTS

Forty-eight studies met the selection criteria for the effectiveness review, of which 65% (31/48) were RCTs, and 17% (8/48) were conducted in the UK. Seven were rated as good quality and 28 as moderate quality. No studies met the selection criteria for the health economics review. There is strong evidence that short periods of kangaroo skin-to-skin contact increased the duration of any breastfeeding for 1 month after discharge [risk ratio (RR) 4.76, 95% confidence interval (CI) 1.19 to 19.10] and for more than 6 weeks (RR 1.95, 95% CI 1.03 to 3.70) among clinically stable infants in industrialised settings. There is strong evidence for the effectiveness of peer support at home (in Manila) for mothers of term, low birthweight infants on any breastfeeding up to 24 weeks (RR 2.18, 95% CI 1.45 to 3.29) and exclusive breastfeeding from birth to 6 months (RR 65.94, 95% CI 4.12 to 1055.70), and for the effectiveness of peer support in hospital and at home for mothers of infants in Special Care Baby Units on providing any breastmilk at 12 weeks [odds ratio (OR) 2.81, 95% CI 1.11 to 7.14; p = 0.01]. There is more limited evidence for the effectiveness of skilled professional support in a US Neonatal Intensive Care Unit on infants receiving any breastmilk at discharge (OR 2.0, 95% CI 1.2 to 3.2, p = 0.004). Multidisciplinary staff training may increase knowledge and can increase initiation rates and duration of breastfeeding, although evidence is limited. Lack of staff training is an important barrier to implementation of effective interventions. Baby Friendly accreditation of the associated maternity hospital results in improvements in several breastfeeding-related outcomes for infants in neonatal units. Limited evidence suggests that cup feeding (versus bottle feeding) may increase breastfeeding at discharge and reduce the frequency of oxygen desaturation. Breastmilk expression using simultaneous pumping with an electric pump has advantages in the first 2 weeks. Pharmaceutical galactagogues have little benefit among mothers who have recently given birth. Our economic analysis found that additional skilled professional support in hospital was more effective and less costly (due to reduced neonatal illness) than normal staff contact. Additional support ranged from 0.009 quality-adjusted life-years (QALYs) to 0.251 QALYs more beneficial per infant and ranged from 66 pounds to 586 pounds cheaper per infant across the birthweight subpopulations. Donor milk would become cost-effective given improved mechanisms for its provision.

CONCLUSIONS

Despite the limitations of the evidence base, kangaroo skin-to-skin contact, peer support, simultaneous breastmilk pumping, multidisciplinary staff training and the Baby Friendly accreditation of the associated maternity hospital have been shown to be effective, and skilled support from trained staff in hospital has been shown to be potentially cost-effective. All these point to future research priorities. Many of these interventions inter-relate: it is unlikely that specific clinical interventions will be effective if used alone. There is a need for national surveillance of feeding, health and cost outcomes for infants and mothers in neonatal units; to assist this goal, we propose consensus definitions of the initiation and duration of breastfeeding/breastmilk feeding with specific reference to infants admitted to neonatal units and their mothers.

Systematic review of antimicrobial treatments for diabetic foot ulcers

BACKGROUND

Foot ulcers in diabetes are associated with increased mortality, illness and reduced quality of life. Ulcer infection impairs healing and antimicrobial interventions may cure infection, aid healing and reduce amputation rates.

OBJECTIVES

To systematically review the evidence for antimicrobial interventions for foot ulcers in diabetes.

METHODS

We searched 16 databases, 11 Internet sites, three books, conference proceedings, a journal and bibliographies in November 2002. We included randomized controlled trials (RCTs) or controlled clinical trials (CCTs).

RESULTS

Twenty-three studies investigated the effectiveness or cost-effectiveness of antimicrobial agents: intravenous antibiotics (n = 8); oral antibiotics (n = 5); topical antimicrobials (n = 4); subcutaneous granulocyte-colony stimulating factor (G-CSF) (n = 4); Ayurvedic preparations (n = 1): and sugar vs. antibiotics vs. standard care (n = 1). The trials were small and too dissimilar to be pooled. There is no strong evidence for any particular antimicrobial agent for the prevention of amputation, resolution of infection, or ulcer healing. Pexiganan cream may be as effective as oral ofloxacin for resolution of infection. Ampicillin and sulbactam cost less than imipenem/cilastatin, G-CSF cost less than standard care and cadexomer iodine dressings may cost less than daily dressings.

CONCLUSIONS

The evidence is too weak to recommend any particular antimicrobial agent. Large studies are needed of the effectiveness and cost-effectiveness of antimicrobial interventions.

Comparison of the early stages of forced unfolding for fibronectin type III modules

The structural changes accompanying stretch-induced early unfolding events were investigated for the four type III fibronectin (FN-III) modules, FN-III(7), FN-III(8), FN-III(9), and FN-III(10) by using steered molecular dynamics. Simulations revealed that two main energy barriers, I and II, have to be overcome to initiate unraveling of FN-III's tertiary structure. In crossing the first barrier, the two opposing beta-sheets of FN-III are rotated against each other such that the beta-strands of both beta-sheets align parallel to the force vector (aligned state). All further events in the unfolding pathway proceed from this intermediate state. A second energy barrier has to be overcome to break the first major cluster of hydrogen bonds between adjacent beta-strands. Simulations revealed that the height of barrier I varied significantly among the four modules studied, being largest for FN-III(7) and lowest for FN-III(10), whereas the height of barrier II showed little variation. Key residues affecting the mechanical stability of FN-III modules were identified. These results suggest that FN-III modules can be prestretched into an intermediate state with only minor changes to their tertiary structures. FN-III(10), for example, extends 12 A from the native "twisted" to the intermediate aligned state, and an additional 10 A from the aligned state to further unfolding where the first beta-strand is peeled away. The implications of the existence of intermediate states regarding the elasticity of fibrillar fibers and the stretch-induced exposure of cryptic sites are discussed.

Behavioural and psychological syndromes in Alzheimer's disease

OBJECTIVES

The origins of behavioural and psychological symptoms of dementia are still poorly understood. By focusing on piecemeal behaviours as opposed to more robust syndrome change valid biological correlates may be overlooked. Our understanding of BPSD via the identification of neuropsychiatric syndromes.

METHODS

We recruited 435 subjects from old age psychiatry and elderly care memory outpatient clinics fulfilling the criteria for diagnosis of probable Alzheimer's disease. Behavioural and psychological symptoms were assessed using the Neuropsychiatric Inventory. Principal components factor analysis was carried out on the composite scores of the 12 symptom domains to identify behavioural syndromes (factors). Results were confirmed by performing three different rotations: Varimax, Equamax and Quartimax.

RESULTS

Four factors were identified (which accounted for 57% of the variance): 'affect' factor-depression/dysphoria, anxiety, irritability/lability and agitation/aggression; 'physical behaviour' factor-apathy, aberrant motor behaviour, sleep disturbance and appetite/eating disturbance; 'psychosis' factor-delusions and hallucinations; 'hypomania' factor-disinhibition and elation/euphoria. These groups were unchanged when different methods of rotation were used.

CONCLUSIONS

We report novel observations that agitation/aggression/irritability cluster within a depressive symptom factor and apathy is found within a physical behaviour factor.

Genome-wide linkage analysis of ADHD using high-density SNP arrays: novel loci at 5q13.1 and 14q12

Previous genome-wide linkage studies applied the affected sib-pair design; one investigated extended pedigrees of a genetic isolate. Here, results of a genome-wide high-density linkage scan of attention-deficit/hyperactivity disorder (ADHD) using an array-based genotyping of approximately 50 K single nucleotide polymorphism (SNPs) markers are presented. We investigated eight extended pedigrees of German origin that were non-related, not part of a genetic isolate and ascertained on the basis of clinical referral. Two parametric analyses maximizing LOD scores (MOD) and a non-parametric analysis for both a broad and a narrow phenotype approach were conducted. Novel linkage loci across all families were detected at 2q35, 5q13.1, 6q22-23 and 14q12, within individual families at 18q11.2-12.3. Further linkage regions at 7q21.11, 9q22 and 16q24.1 in all families, and at 1q25.1, 1q25.3, 9q31.1-33.1, 9q33, 12p13.33, 15q11.2-13.3 and 16p12.3-12.2 in individual families replicate previous findings. High-resolution linkage mapping points to several novel candidate genes characterized by dense expression in the brain and potential impact on disorder-relevant synaptic transmission. Our study provides further evidence for common gene effects throughout different populations despite the complex multifactorial etiology of ADHD.

A retrospective study of the behavioural and psychological symptoms of mid and late phase Alzheimer's disease

AIM

To document the behavioural and psychological symptoms in patients with a diagnosis of established Alzheimer's disease (AD) for at least 3 years.

METHODS

Patients with a > or =3 year history of AD (NINCDS/ADRDA) were recruited from old age psychiatrist and elderly care memory clinics. Information regarding duration of symptoms and non-cognitive symptomatology was obtained during interview with a carer or next-of-kin who had contact with the patient at least 3 times a week and for at least 3 years. MMSE, FAST and NPI including caregiver distress, were used to assess cognition, function and behavioural/psychological disturbance respectively. With each non-cognitive symptom the carer was asked to estimate its onset.

RESULTS

The mean age of patients was 77 years and duration of illness 87 months. Mean MMSE was 8/30 and FAST score 6d. Of the psychological symptoms occurring at any stage, depression (56%), delusions (55%) and anxiety (52%) were most common, with hallucinations, elation and disinhibition occurring less frequently. In general, behavioural changes were more common with apathy occurring in 88% of patients, motor behaviour in 70%, aggression in 66%, irritability and appetite changes in 60% and sleep disturbance in 54%. All symptoms except apathy became less common when the carer was asked if they were still present in the last month. Mean onset of psychological symptoms was 47 months. Mean onset of behavioural symptoms was 48 months. Behavioural disturbance seemed to cause more care-giver distress than psychological change.

CONCLUSION

The results show behavioural and psychological symptoms in AD are common and distressing for carers. They appear to require a consistent period of neurodegeneration in order to emerge.

Effects of an abilities-focused program of morning care on residents who have dementia and on caregivers

OBJECTIVE

To conduct a controlled investigation to examine the effects of an abilities-focused program of morning care on the interaction behaviors and functioning of residents with dementia and on caregivers' interaction behaviors and perceptions of caregiving.

DESIGN

A quasi-experimental, repeated measures design.

SETTING

The study was conducted on four, nursing-home-level cognitive supports units in a geriatric care center. One of the units was randomly selected as the experimental unit; the other three served as controls.

PARTICIPANTS

The final sample consisted of 40 residents (20 each in the experimental and three control groups) and 44 caregivers (16 on the experimental unit and 28 on the three control units).

INTERVENTION

An educational program on delivering abilities-focused morning care, designed by the authors, was provided to caregivers on the experimental unit.

MEASUREMENTS

Measures were taken at baseline and at 3 and 6 months postintervention with regard to residents' interaction behaviors, level of agitation, and level of function and to caregivers' interaction behaviors, perceived ease of caregiving, and level of stress.

RESULTS

Repeated measures analysis of variance (RM-ANOVA) was used to compare the experimental and control groups in regard to changes in the outcomes over time. Results indicated that the abilities-focused program had statistically significant effects on (a) residents' personal attending and calm/functional behaviors, level of agitation, and levels of overall and social function, and (b) caregivers' verbal relevance and personal attending, relaxed, and social/flexible behaviors.

CONCLUSIONS

The evidence suggests that both residents and caregivers benefit from morning care that is oriented toward the abilities of people with dementia.

A systematic review of duplex ultrasound, magnetic resonance angiography and computed tomography angiography for the diagnosis and assessment of symptomatic, lower limb peripheral arterial disease

OBJECTIVES

To determine the diagnostic accuracy and cost-effectiveness of duplex ultrasound (DUS), magnetic resonance angiography (MRA), and computed tomography angiography (CTA), as alternatives to contrast angiography (CA), for the assessment of lower limb peripheral arterial disease (PAD).

DATA SOURCES

Ten electronic databases were searched in April 2004, with an update in May 2005. Six key journals and bibliographies of included studies were also searched and experts in the field were consulted.

REVIEW METHODS

Data extraction and quality assessment were performed in duplicate. Data were analysed according to test type and diagnostic threshold. For the economic analysis, a decision tree was developed and a probabilistic sensitivity analysis performed to incorporate statistical uncertainty into the cost-effectiveness analysis.

RESULTS

A total of 113 studies met the inclusion criteria (including six economic evaluations). For the detection of stenosis greater than 50% in the whole leg, contrast-enhanced (CE) MRA (14 studies) had the highest diagnostic accuracy, with sensitivity ranging from 92 to 99.5% and specificity from 64 to 99%. Two-dimensional (2D) time-of-flight (TOF) MRA (11 studies) was less accurate, with sensitivity ranging from 79 to 94% and specificity from 74 to 92%. 2D phase-contrast (PC) MRA (one study) had a sensitivity of 98% and specificity of 74%. CTA (seven studies) also appeared slightly inferior to CE MRA, with a sensitivity ranging from 89 to 99% and specificity from 83 to 97%, but better than DUS (28 studies), which had a sensitivity ranging from 80 to 98% and specificity from 89 to 99%. There was some indication that CE MRA and DUS were more accurate for detecting stenoses/occlusions above the knee than below the knee or in the pedal artery. The four studies of patient attitudes strongly suggested that patients preferred CE MRA to CA. CA was considered the most uncomfortable test, followed by CE MRA, with CTA being the least uncomfortable. Half of the patients (from a sample who did not suffer from claustrophobia and had no metallic implants) expressed no preference between undergoing TOF MRA or DUS; most of those who did express a preference favoured TOF MRA. In the 55 studies identified for adverse events, MRA was associated with the highest reported proportion. However, the most severe adverse events were more common in patients undergoing CA; although these were rare for both tests. The economic evaluation showed DUS dominated the other alternatives when the whole leg was assessed, by presenting higher effectiveness at a lower cost per quality-adjusted life-year (QALY; i.e. 13,646 pounds per QALY). When the assessment was limited to a section of the leg, either above the knee or below the knee, 2D TOF MRA was the most cost-effective preoperative diagnostic strategy. The incremental cost per QALY for below-the-knee comparisons was equal to 37,024 pounds when 2D TOF MRA was compared with DUS. For above-the-knee comparisons, 2D TOF MRA presented the lowest cost and slightly lower effectiveness compared with CE MRA, with a cost per QALY equal to 13,442 pounds.

CONCLUSIONS

The results of the review suggest that CE MRA has a better overall diagnostic accuracy than CTA or DUS, and that CE MRA is generally preferred by patients over CA. Where available, CE MRA may be a viable alternative to CA. The only controlled trial suggested that the results of DUS were comparable to those of CA, in terms of surgical planning and outcome. This finding conflicts with the results of diagnostic accuracy studies, which reported poor estimates of accuracy for DUS in comparison with CA. There was insufficient evidence to evaluate the usefulness of CTA for the assessment of PAD, particularly newer techniques. The results of the economic modelling suggest that for PAD patients for whom the whole leg is evaluated by a preoperative diagnostic test, DUS dominates the other alternatives by presenting higher effectiveness at a lower cost per QALY. However, when the analysis of stenosis is limited to a section of the leg, either above the knee or below the knee, 2D TOF MRA appears to be the most cost-effective preoperative diagnostic strategy. Further research is needed into a number of areas including the relative clinical effectiveness of the available imaging tests, in terms of surgical planning and postoperative outcome.

Promoting positive affect and diminishing loneliness of widowed seniors through a support intervention

Seniors are most vulnerable to conjugal bereavement. Although social support buffers the effects of bereavement, widows and widowers have lower levels of social support than married individuals. Self-help/support groups can supplement support from their depleted natural networks. Accordingly, the aim of this demonstration project was to examine the impact of support groups on widowed seniors' loneliness, affect, and perceived support. Four face-to-face support groups for widowed seniors were conducted weekly for a maximum of 20 weeks. Participants completed pretest, posttest, and delayed posttest measures of support need and support satisfaction, positive and negative affect, and loneliness/isolation. The statistically significant impacts of the intervention were enhanced support satisfaction, diminished support needs, and increased positive affect. There was a trend toward decreased social isolation and emotional loneliness. In postintervention semistructured interviews, bereaved seniors reported increased hope, improved skills in developing social relationships, enhanced coping, new role identities, and less loneliness. Community health nurse researchers could conduct randomized controlled trials of face-to-face and telephone support groups for bereaved people of all ages. Community health nurse practitioners could benefit from lessons learned about timing, duration, and selection of sensitive outcomes.

Etanercept, infliximab and adalimumab for the treatment of psoriatic arthritis: a systematic review and economic evaluation

BACKGROUND

Etanercept, infliximab and adalimumab are licensed in the UK for the treatment of active and progressive psoriatic arthritis (PsA) in adults who have an inadequate response to standard treatment.

OBJECTIVE

To determine the clinical effectiveness, safety and cost-effectiveness of these biologic agents in the treatment of active and progressive PsA.

DATA SOURCES

Systematic reviews were performed, with data sought from 10 electronic databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Science Citation Index, Conference Proceedings Citation Index - Science, ClinicalTrials.gov, metaRegister of Current Controlled Trials, NHS Economic Evaluation Database, Health Economic Evaluations Database and EconLit) up to June 2009.

REVIEW METHODS

Full paper manuscripts of titles/abstracts considered relevant were obtained and assessed for inclusion by two reviewers according to criteria on study design, interventions, participants and outcomes. Data on study and participant characteristics, efficacy outcomes, adverse effects, costs to the health service and cost-effectiveness were extracted, along with baseline data where reported. The primary efficacy outcomes were measures of anti-inflammatory response, skin lesion response and functional status, and the safety outcome was the incidence of serious adverse events. The primary measure of cost-effectiveness was incremental cost per additional quality-adjusted life-year (QALY). Standard meta-analytic techniques were applied to efficacy data. Published cost-effectiveness studies and the economic analyses submitted to the National Institute for Health and Clinical Excellence (NICE) by the biologic manufacturers were reviewed. An economic model was developed by updating the model produced by the York Assessment Group for the previous NICE appraisal of biologics in PsA.

RESULTS

Pooled estimates of effect demonstrated a significant improvement in patients with PsA for all joint disease and functional status outcomes at 12-14 weeks' follow-up. The biologic treatment significantly reduced joint symptoms for etanercept [relative risk (RR) 2.60, 95% confidence interval (CI) 1.96 to 3.45], infliximab (RR 3.44, 95% CI 2.53 to 4.69) and adalimumab (RR 2.24, 95% CI 1.74 to 2.88), with 24-week data demonstrating maintained treatment effects. Trial data demonstrated a significant effect of all three biologics on skin disease at 12 or 24 weeks. Evidence synthesis found that infliximab appeared to be most effective across all outcomes of joint and skin disease. The response in joint disease was greater with etanercept than with adalimumab, whereas the response in skin disease was greater with adalimumab than with etanercept, although these differences are not statistically significant. Under base-case assumptions, etanercept was the most likely cost-effective strategy for patients with PsA and mild-to-moderate psoriasis if the threshold for cost-effectiveness was £20,000 or £30,000 per QALY. All biologics had a similar probability of being cost-effective for patients with PsA and moderate-to-severe psoriasis at a threshold of £20,000 per QALY.

LIMITATIONS

Limited available efficacy data and difficulty in assessing PsA activity and its response to biologic therapy.

CONCLUSIONS

The data indicated that etanercept, infliximab and adalimumab were efficacious in the treatment of PsA compared with placebo, with beneficial effects on joint symptoms, functional status and skin. Short-term data suggested that these biologic agents can delay joint disease progression and evidence to support their use in the treatment of PsA is convincing. Future research would benefit from long-term observational studies with large sample sizes of patients with PsA to demonstrate that beneficial effects are maintained, along with further monitoring of the safety profiles of the biologic agents.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Platelet beta-secretase activity is increased in Alzheimer's disease

beta-Secretase activity is the rate-limiting step in Abeta peptide production from amyloid precursor protein. Abeta is a major component of Alzheimer's disease (AD) cortical amyloid plaques. beta-Secretase activity is elevated in post mortem brain tissue in AD. The current study investigated whether beta-secretase activity was also elevated in peripheral blood platelets. We developed a novel fluorimetric beta-secretase activity assay to investigate platelets isolated from individuals with AD (n=86), and age-matched controls (n=115). Platelet membrane beta-secretase activity (expressed as initial rate) varied over fourfold between individuals, raising important questions about in vivo regulation of this proteolytic activity. Nonetheless, we identified a significant 17% increase in platelet membrane beta-secretase activity in individuals with AD compared to controls (p=0.0003, unpaired t-test). Platelet membrane beta-secretase activity did not correlate with mini-mental state examination (MMSE) score in the AD group (mean MMSE=17.7, range 1-23), indicating that the increase did not occur as a secondary result of the disease process, and may even have preceded symptom onset.

Plasmid cDNA-directed protein synthesis in a coupled eukaryotic in vitro transcription-translation system

A system is described in which transcription of cDNA clones by bacteriophage T7 RNA polymerase is coupled to translation in the micrococcal nuclease treated rabbit reticulocyte lysate in a single reaction of coupled transcription-translation. The monovalent and divalent cation requirements for translation are dominant for optimum expression in this coupled system, so that transcription is relatively inefficient. Nevertheless, the use of appropriate DNA concentrations leads to the synthesis of sufficient RNA to saturate the protein synthesis capacity of the system. The fidelity and efficiency of expression in this coupled system are high, and the degree of purification of the plasmid DNA is relatively uncritical. The system therefore offers very considerable advantages for rapid screening of 'mini-preparations' of cDNA plasmid constructs for retention of the correct reading frame and expression of the desired protein product.

A series of systematic reviews to inform a decision analysis for sampling and treating infected diabetic foot ulcers

OBJECTIVES

To review systematically the evidence on the performance of diagnostic tests used to identify infection in diabetic foot ulcers (DFUs) and of interventions to treat infected DFUs. To use estimates derived from the systematic reviews to create a decision analytic model in order to identify the most effective method of diagnosing and treating infection and to identify areas of research that would lead to large reductions in clinical uncertainty.

DATA SOURCES

Electronic databases covering period from inception of the database to November 2002.

REVIEW METHODS

Selected studies were assessed against validated criteria and described in a narrative review. The structure of a decision analytic model was derived for two groups of patients in whom diagnostic tests were likely to be used.

RESULTS

Three studies that investigated the performance of diagnostic tests for infection on populations including people with DFUs found that there was no evidence that single items on a clinical examination checklist were reliable in identifying infection in DFUs, that wound swabs perform poorly against wound biopsies, and that semi-quantitative analysis of wound swabs may be a useful alternative to quantitative analysis. However, few people with DFUs were included, so it was not possible to tell whether diagnostic performance differs for DFUs relative to wounds of other aetiologies. Twenty-three studies investigated the effectiveness (n = 23) or cost-effectiveness (n = 2) of antimicrobial agents for DFUs. Eight studied intravenous antibiotics, five oral antibiotics, four different topical agents such as dressings, four subcutaneous granulocyte colony stimulating factor (G-CSF), one evaluated oral and topical Ayurvedic preparations and one compared topical sugar versus antibiotics versus standard care. The majority of trials were underpowered and were too dissimilar to be pooled. There was no strong evidence for recommending any particular antimicrobial agent for the prevention of amputation, resolution of infection or ulcer healing. Topical pexiganan cream may be as effective as oral antibiotic treatment with ofloxacin for the resolution of local infection. Ampicillin and sulbactam were less costly than imipenem and cilastatin, a growth factor (G-CSF) was less costly than standard care and cadexomer iodine dressings may be less costly than daily dressings. A decision analytic model was derived for two groups of people, those for whom diagnostic testing would inform treatment--people with ulcers which do not appear infected but whose ulcer is not progressing despite optimal concurrent treatment--and those in whom a first course of antibiotics (prescribed empirically) have failed. There was insufficient information from the systematic reviews or interviews with experts to populate the model with transition probabilities for the sensitivity and specificity of diagnosis of infection in DFUs. Similarly, there was insufficient information on the probabilities of healing, amputation or death in the intervention studies for the two populations of interest. Therefore, we were unable to run the model to inform the most effective diagnostic and treatment strategy.

CONCLUSIONS

The available evidence is too weak to be able to draw reliable implications for practice. This means that, in terms of diagnosis, infection in DFUs cannot be reliably identified using clinical assessment. This has implications for determining which patients need formal diagnostic testing for infection, on whether empirical treatment with antibiotics (before the results of diagnostic tests are available) leads to better outcomes, and on identifying the optimal methods of diagnostic testing. With respect to treatment, it is not known whether treatment with systemic or local antibiotics leads to better outcomes or whether any particular agent is more effective. Limited evidence suggests that both G-CSF and cadexomer iodine dressings may be less expensive than 'standard' care, that ampicillin/sulbactam may be less costly than imipenem/cilastatin, and that an unlicensed cream (pexiganan) may be as effective as oral ofloxacin. Further research is needed to ascertain the characteristics of infection in people with DFUs that influence healing and amputation outcomes, to determine whether detecting infection prior to treatment offers any benefit over empirical therapy, and to establish the most effective and cost-effective methods for detecting infection, as well as the relative effectiveness and cost-effectiveness of antimicrobial interventions for DFU infection.

Structural insights into the mechanical regulation of molecular recognition sites

Intriguing experimental and computational data are emerging to suggest that mechanical forces regulate the functional states of some proteins by stretching them into nonequilibrium states. Using the extracellular matrix protein fibronectin as an example, we discuss molecular design principles that might control the exposure of a protein's recognition sites, and/or their relative distances, in a force-dependent manner. Fibronectin regulates many cellular functions by binding directly to integrins. Although integrins have a key role in the transduction of force across the cell membrane by coupling the extracellular matrix to the cytoskeleton, the studies reviewed here suggest that fibronectin might be one of the molecules responsible for the initial transformation of mechanical force into a biochemical signal.

Sugammadex for the reversal of muscle relaxation in general anaesthesia: a systematic review and economic assessment

BACKGROUND

Sugammadex (Bridion) is a newly developed agent for the reversal of neuromuscular blockade (NMB) induced by rocuronium or vecuronium. Sugammadex can reverse profound blockade and can be given for immediate reversal and its use would avoid the potentially serious adverse effects of the currently used agent, succinylcholine. Also, sugammadex can reverse NMB more quickly and predictably than existing agents.

OBJECTIVES

To determine the clinical effectiveness and cost-effectiveness of sugammadex for the reversal of muscle relaxation after general anaesthesia in UK practice following routine or rapid induction of NMB.

DATA SOURCES

Medical databases [including MEDLINE, EMBASE, CINAHL, Science Citation Index, BIOSIS and Cochrane Central Register of Controlled Trials (CENTRAL), conference proceedings, internet sites and clinical trials registers] were searched to identify published and unpublished studies. The main searches were carried out in May 2008 and supplemented by current awareness updates up until November 2008.

REVIEW METHODS

For the clinical effectiveness review, randomised controlled trials of sugammadex against placebo or an active comparator (neostigmine + glycopyrrolate) for the reversal of moderate or profound NMB and for immediate reversal (spontaneous recovery from succinylcholine-induced blockade) were included. The primary effectiveness outcome was speed of recovery from NMB, as measured by objective monitoring of neuromuscular function. For the cost-effectiveness review, a de novo economic assessment considered the routine induction of NMB and the rapid induction and/or reversal of NMB, and threshold analyses were carried out on a series of pairwise comparisons to establish how effective sugammadex needs to be to justify its cost.

RESULTS

The review of clinical effectiveness included four randomised active-control trials of sugammadex, nine randomised placebo-controlled trials and five studies in special populations. A total of 2132 titles and abstracts and 265 full-text publications were screened. The included trials indicated that sugammadex produces more rapid recovery from moderate or profound NMB than placebo or neostigmine. Median time to recovery from moderate blockade was 1.3-1.7 minutes for rocuronium + sugammadex, 21-86 minutes for rocuronium + placebo and 17.6 minutes for rocuronium + neostigmine. In profound blockade, median time to recovery was 2.7 minutes for rocuronium + sugammadex, 30 to > 90 minutes for rocuronium + placebo, and 49 minutes for rocuronium + neostigmine. Results for vecuronium were similar. In addition, recovery from NMB was faster with rocuronium reversed by sugammadex 16 mg/kg after 3 minutes (immediate reversal) than with succinylcholine followed by spontaneous recovery (median time to primary outcome 4.2 versus 7.1 minutes). The evidence base for modelling cost-effectiveness is very limited. However, assuming that the reductions in recovery times seen in the trials can be achieved in routine practice and can be used productively, sugammadex [2 mg/kg (4 mg/kg)] is potentially cost-effective at its current list price for the routine reversal of rocuronium-induced moderate (profound) blockade, if each minute of recovery time saved can be valued at approximately 2.40 pounds (1.75 pounds) or more. This is more likely to be achieved if any reductions in recovery time are in the operating room (estimated value of 4.44 pounds per minute saved) rather than the recovery room (estimated value of 0.33 pounds per minute saved). The results were broadly similar for rocuronium- and vecuronium-induced blockade. For rapid reversal of NMB it appeared that any reduction in morbidity from adopting sugammadex is unlikely to result in significant cost savings.

LIMITATIONS

The evidence base was not large and many of the published trials were dose-finding and safety studies with very small sample sizes. Also, some relevant outcomes, in particular patient experience/quality of life and resources/costs used, were either not investigated or not reported. In addition, it is likely that the patients included in the efficacy trials were relatively young and in good general health compared with the overall surgical population. Regarding the economic evaluation, there appears to be no evidence linking measures of clinical efficacy to patients' health-related quality of life and mortality risks.

CONCLUSIONS

Sugammadex may be a cost-effective option compared with neostigmine + glycopyrrolate for reversal of moderate NMB and also provides the facility to recover patients from profound blockade. Rocuronium + sugammadex could be considered as a replacement for succinylcholine for rapid induction (and reversal) of NMB, although this may not be a cost-effective option in some types of patient at current list prices for sugammadex. Considerable uncertainties remain about whether the full benefits of sugammadex can be realised in clinical practice.

Cigarette smoking and nicotine gum (0, 2 and 4 mg): effects upon four visual attention tasks

Sixteen regular smokers, abstinent for 12 h prior to testing, were assessed on a battery of four visual attention tasks: rapid visual information processing (RVIP), letter cancellation, Stroop, and width of attention. Each subject was assessed under four conditions: placebo gum, 2 mg nicotine gum, 4 mg nicotine gum, and cigarette smoking (own brand), with the order of drug administration determined by latin square. Pre-post drug difference scores for letter cancellation response time demonstrated a significant monotonic dose-response function, with significantly faster performance following cigarette than placebo. RVIP response time and target detection were also affected by nicotine. One RVIP task parameter demonstrated a significant monotonic dose-response function, with highest performance under smoking. Other RVIP measures demonstrated curvilinear dose-response functions, with highest performance under nicotine gum, and broadly similar performance after placebo gum and cigarette smoking. Monotonic and inverted-U arousal/performance functions similar to these have been demonstrated in previous research with nicotine. In contrast to the significant changes in sustained attention, neither width of attention nor Stroop task performance (an index of distractability) was affected by nicotine. Resting heart rate and subjective 'need for a cigarette' showed the predicted monotonic dose-response functions following nicotine. There were no significant changes in any Profile of Mood State factor.

Galantamine for vascular cognitive impairment

BACKGROUND

Vascular dementia is the second most common form of dementia. Cholinesterase inhibitors modestly improve a broad range of symptoms in some patients with Alzheimer's disease through enhancement of cholinergic neurotransmission. These drugs may also be beneficial in vascular dementia as reductions in acetylcholine and acetyltransferase activity have been reported.

OBJECTIVES

To assess the efficacy of galantamine in the treatment of people with vascular cognitive impairment or vascular dementia or "mixed" dementia.

SEARCH STRATEGY

Trials were identified from a search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 19 April 2005 using the terms: galantamine. galanthamine, reminyl. All major health care databases and many ongoing trial databases within the scope of the group are searched regularly to keep this Register up to date.

SELECTION CRITERIA

All unconfounded randomised double-blind trials comparing galantamine with placebo were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two RCTs fulfilling the inclusion criteria were included in this review. Two reviewers independently extracted the data from these two inclusion studies.

MAIN RESULTS

Two trials employing randomized, double-blind, parallel-group methodology were included. GAL-INT-6 reported sub-group data for a pure population of vascular dementia patients showing no significant differences in Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog/11) and Clinician's Interview-based Impression of Change (CIBIC-plus) when galantamine was compared against placebo. When data combining patients with vascular dementia diagnosed according to recognised criteria with a population of patients with Alzheimer's disease and coincidental radiographic findings of cerebrovascular disease was analysed, statistically significant improvements in cognition (ADAS-cog), global functioning (CIBIC-plus), activities of daily living (DAD) and behaviour (NPI) were noted. In the galantamine treated group, significantly higher numbers of patients dropped out and withdrew due to an adverse event. Limited data was available at the time of publication for a second larger trial (GAL-INT-26) involving patients with vascular dementia diagnosed using standard criteria. Statistically significant benefits favouring galantamine over placebo in assessments of cognition (ADAS-cog/11; p < 0.001) and executive function (Executive Interview, EXIT-25, p = 0.041) were recorded. No differences in outcome in measures of behaviour (Neuropsychiatric Inventory, NPI), daily living (Alzheimer's Disease Cooperative Study-Activities of Daily Living inventory, ADCS-ADL) and global functioning (CIBIC-plus) in this trial were seen.

AUTHORS' CONCLUSIONS

Limited data were available when considering the impact of galantamine on vascular dementia or vascular cognitive impairment. The data available at the time of review suggest some advantage over placebo in the areas of cognition and executive functioning in one trial but this was not seen in a second trial which included smaller numbers of relevant patients. In both considered trials galantamine produced higher rates of gastrointestinal side-effects. More studies are needed before firm conclusions can be drawn.

Fluorescence-based enzymatic assay by capillary electrophoresis laser-induced fluorescence detection for the determination of a few beta-galactosidase molecules

beta-Galactosidase can be assayed by monitoring the generation of the fluorescent products, fluorescein-mono-beta-D-galactopyranoside and fluorescein, when the fluorogenic substrate fluorescein-di-beta-D-galactopyranoside is used. We have used capillary electrophoresis with ultrasensitive laser-induced fluorescence detection to monitor the formation of the fluorescent products of off-column enzymatic reactions. By analyzing as little as 40 pl of the enzymatic mixture we obtain limits of detection of 6.5 x 10(-14) M beta-galactosidase or 1.6 molecules based on the detection of fluorescein-mono-beta-D-galactopyranoside.

Genome-wide SNP genotyping study using pooled DNA to identify candidate markers mediating susceptibility to end-stage renal disease attributed to Type 1 diabetes

AIMS

Genetic factors play a major role in the progression of kidney disease in diabetes. To identify candidate single nucleotide polymorphisms (SNPs) with potential effects on susceptibility to end-stage renal disease (ESRD), we performed a whole genome association scan using pooled DNA from Caucasian individuals with Type 1 diabetes.

METHODS

We utilized the Illumina Infinium II HumanHap 550 beadchip platform to genotype 555 352 SNPs in DNA pools comprised of 547 cases with ESRD and 549 control subjects with Type 1 diabetes duration > 20 years and no ESRD. Pooled probe intensity was used to predict mean allele frequency (MAF) for each locus. Individual genotyping was performed using the iPLEX assay in conjunction with the MassARRAY platform (Sequenom).

RESULTS

We identified 2870 markers showing substantial differences in MAF (5.0-10.7%) between pools. To initiate validation of these findings, we genotyped 22 high-ranking markers in 462 individuals with ESRD and 470 unaffected control subjects selected from the genome-wide SNP genotyping study sample. We observed the strongest evidence for association between ESRD and rs1749824, located in the ZMIZ1 gene [OR = 1.47 (1.21-1.78) per copy of T allele; P = 8.1 x 10(-5)] and rs9298190, located in the musculin gene [OR = 1.56 (1.28-1.91) per copy of C allele; P = 1.6 x 10(-5)]. Evidence for nominal association with markers in or near the IRS2, TMPO, BID, KLRA1, ELMO1 and CNDP1 genes was also observed (P < or = 0.0006).

CONCLUSIONS

These findings identify several novel loci which may contribute to ESRD susceptibility in individuals with Type 1 diabetes.