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PubMed2025

Expanding kinetoplastid genome annotation through protein structure comparison.

Kinetoplastids belong to the Discoba supergroup, an early divergent eukaryotic clade. Although the amount of genomic information on these parasites has grown substantially, assigning gene functions through traditional sequence-based homology methods remains challenging. Recently, significant advancements have been made in in-silico protein structure prediction and algorithms for rapid and precise large-scale protein structure comparisons. In this work, we developed a protein structure-based homology search pipeline (ASC, Annotation by Structural Comparisons) and applied it to transfer biological information to all kinetoplastid proteins available in TriTrypDB, the reference database for this lineage. Our pipeline enabled the assignment of structural similarity to a substantial portion of kinetoplastid proteins, improving current knowledge through annotation transfer. Additionally, we identified structural homologs for representatives of 6,700 uncharacterized proteins across 33 kinetoplastid species, proteins that could not be annotated using existing sequence-based tools and databases. As a result, this approach allowed us to infer potential biological information for a considerable number of kinetoplastid proteins. Among these, we identified structural homologs to ubiquitous eukaryotic proteins that are challenging to detect in kinetoplastid genomes through standard genome annotation pipelines. The results (KASC, Kinetoplastid Annotation by Structural Comparison) are openly accessible to the community at kasc.fcien.edu.uy through a user-friendly, gene-by-gene interface that enables visual inspection of the data.

Kinetoplastida↗

PubMed2002

Comparative evaluation of the DPX and DPX-IQ lunar densitometer systems following software upgrade.

Bone densitometry research departments perform system and software upgrades infrequently in order to maintain high precision. This study compares the results obtained on a Lunar densitometer with DPX, and DPX-IQ installed to achieve year 2000 compliance. The DPX-IQ provides an improved femur edge detection algorithm with an expanded reference database. Two hundred data files for each measurement site acquired on DPX were reanalyzed on DPX-IQ. There was no change to the bone mineral density (BMD), bone mineral content (BMC), T-scores or Z-scores for the L2-L4 spine, radius (ultradistal and 33%), and total body. There was a significant high correlation for the femoral neck BMD (r = 0.98; p < 0.05). The mean differences in BMD, BMC, T-scores, and Z-scores at the femoral neck and Ward's and trochanteric regions were not significant (p > 0.05). The limits of agreement within the 95% confidence interval for the femoral neck BMD using the Bland and Altman method was between -0.057 and 0.063 g/cm(2). This order of magnitude magnifies the long-term precision error and alters the usual confidence limits for interpretation of true change in densitometry practice. Therefore, it is important for reanalysis of DPX data files with the DPX-IQ to be performed so that longitudinal changes in BMD can be accurately assessed.

Absorptiometry, Photon↗

PubMed2004

Official positions of the International Society for Clinical Densitometry.

The International Society for Clinical Densitometry (ISCD) has convened two Position Development Conferences at which a panel of experts agreed on recommendations for performance and clinical applications of bone density testing. These recommendation were reviewed by the ISCD Board of Directors, and those approved by the board are now official positions of the ISCD. These include (1) indications for bone density testing, (2) reference databases for T-scores, (3) standards for performing central dual-energy X-ray absorptiometry (DXA) for diagnosis, (4) interpretation of peripheral bone density results, (5) diagnosis of osteoporosis in postmenopausal women, (6) diagnosis of osteoporosis in men, (7) diagnosis in premenopausal women, (8) diagnosis in children, (9) indications and interpretation for serial bone mass measurement, (10) technical standards for phantom scanning and calibration, (11) technical standards for cross-calibration of DXAsystems, and (12) standards for reporting of bone density results including correct nomenclature and preferred number of decimal digits.

Absorptiometry, Photon↗

PubMed2004

Diagnosis of osteoporosis in men, premenopausal women, and children.

The World Health Organization (WHO) classification of bone mineral density is based on population studies in postmenopausal women. However, the increased use of bone densitometry has raised questions regarding the applicability of this classification to men, premenopausal women, and children. These questions were addressed at the International Society for Clinical Densitometry 2003 Position Development Conference. T-scores can be used and a diagnosis of osteoporosis made for T-scores of -2.5 or less (male reference database) in men age 65 yr and older and in men from 50 to 64 yr of age if other risk factors for fracture are present. The WHO classification should not be applied to premenopausal women. Men and premenopausal women with secondary causes of low bone density or bone loss may be clinically diagnosed with osteoporosis, taking bone density into consideration. In children and adolescents (males and females less than 20 yr of age), there are no densitometric criteria for diagnosing osteoporosis. If Z-scores are -2.0 or less (using pediatric databases of age-matched controls), then a characterization such as "low bone density for chronologic age" is appropriate. In men under 50 yr of age, premenopausal women, and children, Z-scores, not T-scores, should be used when reporting bone density results.

Absorptiometry, Photon↗

PubMed2005

Pharmacotherapy of osteoporosis in men.

Osteofragility fractures occur in men due to a compromise in bone strength, coupled with either trauma or a fall. In men >or= 65years of age, osteoporosis can be defined as bone mineral density (at the proximal femur, spine or distal forearm) of 2.5 standard deviations or less below the mean for a normal young adult man, using a male reference database (i.e., T-score value of 60 years will suffer an osteoporotic fracture [3]. Spinal fractures occur in 5% of men (compared with 16% of women) and hip fractures in 6% of men (compared with 18% of women) > 50 years of age [8]. The risk of hip fracture increases by approximately 2.6-fold for each standard deviation decrease in bone density measured at the hip [12,13]. At present, the life expectancy for men has increased to a mean age of 76.8 years. With men now living longer, they can be expected to develop multiple coexisting illnesses contributing to bone loss and an increased likelihood of falling and fragility fractures [5,14,15]. It is estimated that 30 - 60% of men presenting with spinal fractures have another illness contributing to their bone disease [4,6-10,16-20]. The ideal therapy for men with osteoporosis should include an intervention which significantly increases bone strength and reduces fracture rates, is safe, easy to administer and economical. This review outlines the current treatment strategies available for men with osteoporosis.

Aging↗

PubMed2000

Meta-analysis of dietary essential fatty acids and long-chain polyunsaturated fatty acids as they relate to visual resolution acuity in healthy preterm infants.

OBJECTIVE: To derive combined estimates of visual resolution acuity differences between healthy preterm infants consuming different compositions and ratios of essential fatty acids (EFAs) and docosahexaenoic acid (DHA), an omega-3 (n-3) long-chain polyunsaturated fatty acid (LCPUFA). DATA SOURCES: Electronic biomedical reference database (Medline and Health Star from 1965 to July 1999) searches with index terms omega-3, n-3, infant, vision, acuity, and human. Current review article, monograph, and book chapter bibliography/reference section hand searches. STUDY SELECTION: A total of 5 original articles and 4 review chapters were reviewed for details on study design, conduct, and outcome. Four prospective trials of EFA/LCPUFA supplementation were included in these analyses. For behaviorally based outcomes, there were 2 randomized comparisons each at </=1, 2, 6, 9, and 12 months of corrected age and 4 randomized comparisons at 4 months of corrected age. For electrophysiologically based outcomes (visual-evoked potential), there were 2 randomized comparisons each at </=1 and approximately 4 months of corrected age. DATA EXTRACTION: Dietary composition and EFA/LCPUFA balance, study design, and analytic characteristics (duration of feeding, source of EFAs/LCPUFAs, number of subjects in study population, number of subjects analyzed, and basis for estimating age), and experiment-based characteristics (location, number or sites, design, vision tests employed, testing protocol, and ophthalmic examination) were recorded independently by 2 researchers with a standardized protocol. DATA SYNTHESIS: The relative difference in visual resolution acuity between groups of infants who received a source of dietary EFAs/LCPUFAs and groups who did not was computed and then analyzed with the DerSimonian and Laird random-effects method. RESULTS: Analysis of the randomized comparisons (DHA-supplemented formula vs DHA-free formula) showed significant differences in visual resolution acuity at 2 and 4 months of age. Combined estimates of behaviorally based visual resolution acuity differences at these ages were.47 +/-.14 octaves and.28 +/-.08 octaves, respectively. A 1-octave difference is a reduction in the width of the stimulus elements by 50%. CONCLUSION: These results support efficacy of n-3 LCPUFA intake in early visual system development, although supplementation safety issues still must be addressed through larger randomized trials. Whether n-3 intake confers lasting advantage in visually based process development across the life-span is still to be determined.

Dietary Supplements↗

PubMed2002

Shamanism or science?

The interconnection of the three organismic levels, metabolism, morphology, and biogeography, can now be amplified into a multipart architecture, introducing plant bioactivity through ethnobotany-oriented descriptions. Only via such an integrative model, the diverse organismic levels can be connected within a more holistic, realistic scheme. Construction of qualitative and quantitative models via evolutionarily conceived implantation into dahlgrenograms and Sporne indices, allows ethnobotany to acquire predictive validity. The coherence of such systems was demonstrated by comparison of the vast ethnobotanical Brazilian database by Pio Corrêa with relatively very minute databases referring to three Amazonian Indian societies.

Bolivia↗

PubMed2003

Improved protocol for SAGE tag-to-gene allocation.

Serial analysis of gene expression (SAGE) is a powerful method for large-scale analysis of gene expression patterns. SAGE yields digital information on transcript abundance by the use of short sequence fragments (tags). Because SAGE does not require a priori knowledge of the expressed genes in the starting material, SAGE can be used for gene discovery. Unfortunately, correct tag-to-gene discovery. Unfortunately, correct tag-to-gene allocation after SAGE remains problematic when the short sequence of the tag corresponds to more than one gene in the reference database or when novel yet uncloned genes were detected. To overcome this problem, we developed an improved protocol for the proper identification of tag-corresponding genes. It relies on the isolation of 3'-terminal cDNA restriction fragments by the use of paramagnetic streptavidin beads and the ligation of linkers before the amplification step. Our protocol benefits from additional information encoded in each SAGE tag: its location 3'-terminal to the last NlaIII restriction site in the cDNA. In contrast to previously described protocols, stringent PCR conditions can be applied because of the length of the specific primers, which are composed of linker- and tag-specific sequences. Additionally, we demonstrate that our protocol yields quantitative information that can be used for further expression analysis of specific SAGE tags.

Animals↗

PubMed2005

Preclinical drug safety analysis by chemogenomic profiling in the liver.

The economic hurdles of drug development and the emergence of genomic technologies such as chemogenomics are combining to shift the existing paradigms in preclinical drug development. Today, the information gleaned from high content molecular data has begun to augment traditional approaches to the assessment of drug safety. The optimal approach is a hybrid strategy employing chemogenomic data and gene expression-based biomarkers of drug efficacy and toxicity to supplement low content and insensitive methods for risk assessment and mechanistic evaluation of drug candidates. Large reference databases of chemogenomic data are essential to the derivation and validation of accurate and predictive gene expression biomarkers. An example of the development of a predictive biomarker for hepatic bile duct hyperplasia is described herein. As gene expression technologies improve, biomarkers will achieve higher throughput, and become more cost effective and increasingly accurate. This will elevate the value of chemogenomics in drug development, shift attrition to earlier in the process, and reduce the overall cost of drug development. Over the past 2 to 3 years, the transition of chemogenomics from a research tool to a decision-making tool has begun and regulatory agencies are anxiously awaiting implementation of this technology to make faster and more informed evaluations of potential drugs.

Animals↗

PubMed2002

Applications of computer software for the interpretation and management of mass spectrometry data in pharmaceutical science.

The rapid growth of mass spectrometry (MS)-based computer software applications has been fueled by the unprecedented need to capture and analyze MS data and provide the information necessary for decision-making. Shorter timelines and a significantly greater number of samples has resulted in a tremendous focus on streamlined approaches that provide scientists, managers, and executives the capability to readily obtain, or even request, the necessary information that leads to accelerated product development. The generation of analytical data using roboticized high-throughput hardware has produced a bottleneck since data can be generated faster than it can be analyzed. New techniques including MS/MS and accurate mass experiments are feasible only using computers to capture and manage the enormous amounts of data necessary to perform the experiments. Whatever the nature of the experiments conducted, the MS analysis strategy is to extract the appropriate information required for decision-making in as facile a manner as possible. We will review here a survey of the creation of commercial and laboratory specific reference databases and associated searching algorithms and also recent efforts to introduce advancedprocessing and analysis algorithms to the hands of the masses, specifically as an aid to structure elucidation.

Chemistry, Pharmaceutical↗

PubMedDate not supplied

Conservative versus surgical treatment of mallet finger: a pooled quantitative literature evaluation.

BACKGROUND: Although common, mallet finger represents a spectrum of injuries for which there are many questions about the best form of treatment. A long-standing controversy continues as to strategies and techniques of treatment. This quantitative literature analysis is the first that makes use of an evidence-based evaluation process to pool across studies the outcomes of conservative versus surgical treatment of closed mallet finger injuries of both acute and chronic or recurrent types. METHODS: Published articles in English were sought using multiple methods, including the MEDLINE and EMBASE databases, reference review, and correspondence with selected experts. Both observational and randomized trials were included. Results were summarized in terms of 95 percent confidence intervals, and sensitivity analysis was performed for two other amounts of residual extensor lag. RESULTS: Of the 41 reports retrieved, 26 met inclusion criteria, including 21 for initial acute treatment (1146 pooled digits) and 5 for chronic or recurrent treatment (148 pooled digits). Successful outcomes were found in about 77 percent of mallet fingers treated conservatively by splintage, including 480 patients who were observed for a 2-year period. Patient satisfaction with conservative treatment was found to be about 83 percent in 6 studies recording overall patient satisfaction (315 pooled patients). Successful outcomes of surgical treatment for acute mallet finger averaged about 85 percent in 3 studies (60 pooled digits) and about 73 percent in 5 studies of chronic or recurrent mallet finger. CONCLUSIONS: Conservative treatment of at least 80 percent of mallet finger injuries is safe, effective, well accepted by patients, and cost efficient compared with surgical treatment. Multiple types of surgical procedures are available when surgery is indicated for a limited number of open or otherwise complex mallet finger injuries as well as for chronic or recurrent mallet finger.

Chronic Disease↗

PubMedDate not supplied

Group visits: a qualitative review of current research.

PURPOSE: The group visit model has emerged as one possible solution to problems posed by the limitations of current structures of care and the demands of a growing chronic illness load. In this article, we summarize current group visit research and develop suggestions for furthering this care model. METHODS: An electronic review of all group visit articles published from the years 1974 to 2004 was conducted via the PubMed and MedLine databases. Reference sections of articles thus obtained were mined for additional citations. Articles were excluded if: (1) they were not research studies (ie, purely descriptive, with no evaluative component); or (2) the group visit intervention was subsumed under larger primary or hospital-based interventions. RESULTS: Although the heterogeneity of the studies presented renders the assessment of this care model problematic, there is sufficient data to support the effectiveness of group visits in improving patient and physician satisfaction, quality of care, quality of life, and in decreasing emergency department and specialist visits. CONCLUSION: Group visits are a promising approach to chronic care management for the motivated patient. Future research may benefit, however, from abandoning old nomenclatures and clearly defining the structure, processes of care, content of visits, and appropriate outcome measures.

Ambulatory Care↗

PubMed2003

Clinical and cost-effectiveness of capecitabine and tegafur with uracil for the treatment of metastatic colorectal cancer: systematic review and economic evaluation.

OBJECTIVES: To evaluate the clinical and cost-effectiveness of capecitabine and tegafur with uracil (UFT/LV) as first-line treatments for patients with metastatic colorectal cancer, as compared with 5-fluorouracil/folinic acid (5-FU/FA) regimens. DATA SOURCES: Electronic databases, reference lists of relevant articles and sponsor submissions were also consulted. REVIEW METHODS: Systematic searches, selection against criteria and quality assessment were performed to obtain data from relevant studies. Costs were estimated through resource-use data taken from the published trials and the unpublished sponsor submissions. Unit costs were taken from published sources, where available. An economic evaluation was undertaken to compare the cost-effectiveness of capecitabine and UFT/LV with three intravenous 5-FU/LV regimens widely used in the UK: the Mayo, the modified de Gramont regimen and the inpatient de Gramont regimens. RESULTS: The evidence suggests that treatment with capecitabine improves overall response rates and has an improved adverse effect profile in comparison with 5-FU/LV treatment with the Mayo regimen, with the exception of hand-foot syndrome. Time to disease progression or death after treatment with UFT/LV in one study appears to be shorter than after treatment with 5-FU/LV with the Mayo regimen, although it also had an improved adverse effect profile. Neither capecitabine nor UFT/LV appeared to improve health-related quality of life. Little information on patient preference was available for UFT/LV, but there was indicated a strong preference for this over 5-FU/LV. The total cost of capecitabine and UFT/LV treatments were estimated at 2111 pounds and 3375 pounds, respectively, compared with the total treatment cost for the Mayo regimen of 3579 pounds. Cost estimates were also presented for the modified de Gramont and inpatient de Gramont regimens. These were 3684 pounds and 6155 pounds, respectively. No survival advantage was shown in the RCTs of the oral drugs against the Mayo regimen. Cost savings of capecitabine and UFT/LV over the Mayo regimen were estimated to be 1461 pounds and 209 pounds, respectively. Drug acquisition costs were higher for the oral therapies than for the Mayo regimen, but were offset by lower administration costs. Adverse event treatment costs were similar across the three regimens. It was inferred that there was no survival difference between the oral drugs and the de Gramont regimens. Cost savings of capecitabine and UFT/LV over the modified de Gramont regimen were estimated to be 1353 pounds and 101 pounds, respectively, and over the inpatient de Gramont regimen were estimated to be 4123 pounds and 2870 pounds, respectively. CONCLUSIONS: The results show that there are cost savings associated with the use of oral therapies. No survival difference has been proven between the oral drugs and the Mayo regimen. In addition, no evidence of a survival difference between the Mayo regimen and the de Gramont regimens has been identified. However, improved progression-free survival and an improved adverse event profile have been shown for the de Gramont regimen over the Mayo regimen. Further research is recommended into the following areas: quality of life data should be included in trials of colorectal cancer treatments; the place of effective oral treatments in the treatment of colorectal cancer, the safety mechanisms needed to ensure compliance and the monitoring of adverse effects; the optimum duration of treatment; the measurement of patient preference; and a phase III comparative trial of capecitabine and UFT/LV versus modified de Gramont treatment to determine whether there was any survival advantage and to collate the necessary economic data.

Antimetabolites, Antineoplastic↗

PubMed2003

Clinical and cost-effectiveness of new and emerging technologies for early localised prostate cancer: a systematic review.

OBJECTIVES: To evaluate the clinical and cost-effectiveness of new and emerging technologies for early, localised prostate cancer. DATA SOURCES: Electronic databases, reference lists of relevant articles and various health services research-related resources. REVIEW METHODS: A list of new and emerging technologies was identified and agreed. A systematic review was undertaken and selected studies were reviewed against a set of criteria. An economic model was developed and used to compare the specified newer treatments with the traditional approaches. RESULTS: For neoadjuvant hormonal therapy, no evidence of benefit was seen in terms of biochemical disease-free survival. For adjuvant hormonal therapy, there was no evidence of benefit in terms of survival, but some conflicting evidence that higher risk patients may benefit. The largest number of studies reported results for brachytherapy, where some evidence suggested that it may be more effective than standard treatments for lower risk patients, although less effective for intermediate- and high-risk patients, in terms of biochemical disease-free survival. Lower quality evidence reported fewer complications than for standard treatments. Higher quality evidence suggested that disease-specific quality of life (QoL) for brachytherapy patients was lower than for patients receiving standard treatments. The review of three-dimensional conformal radiotherapy (3D-CRT) considered treatment-related morbidity, where significantly fewer gastrointestinal complications occurred than with standard radiotherapy. It was suggested that higher radiation doses achieved better disease control, although patient characteristics were often reported as independent indicators of control. The review of intensity-modulated conformal radiotherapy suggested that late gastrointestinal toxicity may be reduced compared with 3D-CRT. For cryotherapy, high rates of impotence were reported. Owing to the paucity and poor quality of evidence identified for other interventions, conclusions regarding their clinical effectiveness cannot be drawn. Cost-effectiveness estimates were based on the impact of adverse events on quality-adjusted life-years and the assessment was restricted to brachytherapy, 3D-CRT and cryotherapy compared with standard treatments. Of the new treatments included, only cryotherapy appeared not to be potentially cost-effective compared with traditional treatments, owing to the associated high incidence of impotence. CONCLUSIONS: The results of the clinical effectiveness review should be viewed in the context of the quality of the available evidence. Very few randomised controlled trials (RCTs) were identified, with the majority of included studies being descriptive case series, open to patient selection bias and measuring surrogate end-points with short-term follow-up. It is difficult therefore to draw conclusions on the relative benefits or otherwise of the newer technologies owing to the lack of substantive evidence of any quality and the lack of comparisons between the newer technologies and with standard treatments. Given the lack of high-quality clinical evidence with long-term follow-up and the uncertainty surrounding the assumptions in the economic analysis, the following areas are recommended for further research: RCTs with sufficient follow-up to measure benefits in terms of overall survival to include QoL measurement to establish trade-offs between potential adverse events and benefits of treatment; the identification of prognostic risk factors among men diagnosed with early prostate cancer; QoL studies to compare the utility of health states among patients on active monitoring, patients receiving treatment and the comparable healthy population; the relationship between surrogate end-points and survival; and the adoption of standard definitions for adverse events.

Cost-Benefit Analysis↗

PubMed2003

Systematic review and economic decision modelling for the prevention and treatment of influenza A and B.

OBJECTIVES: To establish the clinical and cost-effectiveness of amantadine, oseltamivir and zanamivir compared to standard care for the treatment and prevention of influenza. DATA SOURCES: Electronic databases. Reference lists of identified articles and key publications. Relevant trials. REVIEW METHODS: A systematic review and meta-analysis of the randomised evidence was undertaken to investigate the effectiveness of oseltamivir and zanamivir compared to standard care for treatment and prophylaxis use for influenza A and B. An additional systematic review of the effectiveness of amantadine for treatment and prophylaxis use for influenza A in children and the elderly was also undertaken. Economic decision models were constructed to examine the cost-effectiveness and cost-utility of the alternative strategies for treating and preventing influenza A and/or B. This was informed by the systematic reviews outlined above and additional sources of information where required. RESULTS: The systematic review of the treatment of influenza found that oseltamivir reduced the median duration of symptoms in the influenza positive group by 1.38 days for the otherwise healthy adult population, 0.5 day for the high-risk population, and 1.5 days for the children population. This compared to 1.26 days, 1.99 days, and 1.3 for the similar groups for inhaled zanamivir. The systematic review of the prevention of influenza found that the relative risk reduction for oseltamivir was between approximately 75 and 90% and approximately 70 and 90% for inhaled zanamivir depending on the strategy adopted and the population under consideration. For the economic model a base case was constructed that focussed primarily on the health benefits generated by shortening the period of influenza illness. This base case found that, compared to standard care, the estimated cost per quality-adjusted life year ranged from pound 6190 to pound 31,529 for healthy adults, from pound 4535 to pound 22,502 for the 'high-risk' group, from pound 6117 to pound 30,825 for children, and from pound 5057 to pound 21,781 for the residential care elderly population. The base case model included valuations of the health effects of pneumonia (and otitis media in the children's model) based on observed rates in the trials. However it does not include the cost of hospitalisations as only very limited data was available for the effects of antivirals on hospitalisation rates. As for mortality rates, deaths from influenza were rare in trials of neuraminidase inhibitors (NIs). Therefore, suitable data on mortality were not available from these sources. As avoided hospitalisation costs and avoided mortality are potentially important we also carried out sensitivity analysis that involved extrapolating the observed reductions in pneumonias in the NI trials to hospitalisations and deaths. In all four models the cost-effectiveness of NIs is substantially improved by this extrapolation. For prophylaxis, antiviral drugs were compared with vaccination as preventative strategies. In all cases the cost-effectiveness ratios for vaccination were either low or cost-saving. In the base case the cost-effectiveness of antivirals was relatively unfavourable, there were scenarios relating to the elderly residential care model where antivirals as an additional strategy could be cost-effective. CONCLUSIONS: The cost-effectiveness varies markedly between the intervention strategies and target populations. The estimate of cost effectiveness is also sensitive to variations in certain key parameters of the model, for example the proportion of all influenza-like illnesses that are influenza. The effectiveness literature that was used to inform the economic decision model spans many decades and hence great caution should be exercised when interpreting the results of indirect intervention comparisons from the model. Further randomised trials making direct comparisons would be valuable to verify the model's findings.

Antiviral Agents↗

PubMed2004

Newer hypnotic drugs for the short-term management of insomnia: a systematic review and economic evaluation.

OBJECTIVES: To assess the clinical and cost-effectiveness of zaleplon, zolpidem and zopiclone (Z-drugs) compared with benzodiazepines. DATA SOURCES: Electronic databases, reference lists of retrieved articles and pharmaceutical company submissions. REVIEW METHODS: Randomised controlled trials (RCTs) that compared either benzodiazepines to the Z-drugs or any two of the non-benzodiazepine drugs in patients with insomnia were included in the review. Data on the following outcome measures were considered: sleep onset latency, total sleep duration, number of awakenings, quality of sleep, adverse effects and rebound insomnia. A search was also undertaken for any study designs that evaluated issues related to adverse events (e.g. dependency and withdrawal symptoms). Full economic evaluations that compared two or more options and considered both costs and consequences including cost-effectiveness, cost-utility analysis or cost-benefit analysis undertaken in the context of high-quality RCTs were considered for inclusion in the review. RESULTS: Twenty-four studies, involving a total study population of 3909 patients, met the inclusion criteria. These included 17 studies comparing a Z-drug with a benzodiazepine and seven comparing a Z-drug with another Z-drug. The diversity of possible comparisons and the range of outcome measures in the review may be confusing. Outcomes were rarely standardised and, even when reported, differed in interpretation. In addition, variations in assessment and variety in the level of information provided make study comparisons difficult. As a result, meta-analysis has been possible on only a small number of outcomes. However, some broad conclusions might be reached based on the limited data provided. The existing published economic literature in this area is very limited. No relevant economic evaluations were identified for inclusion in the review. The industry submissions did not include detailed evidence of cost-effectiveness. Given the lack of robust clinical evidence, no economic model describing the costs and benefits of the newer hypnotic drugs for insomnia was developed. The systematic review provided in this report suggests that an agnostic approach to cost-effectiveness is required at this stage. In the short-term, no systematic evidence is available concerning significant outcome variations between either the different classes of drugs or between individual drugs within each class. Within this short-term horizon, the one element that does vary significantly is the acquisition cost of the individual drugs. CONCLUSIONS: The short-acting drugs seem equally effective and safe with minor differences that may lead a prescriber to favour one over another in different patients. There is no evidence that one is more cost-effective than any other. Analysis of the additional costs to the NHS, depending on the rate of change from benzodiazepine prescriptions to Z-drug prescriptions, at current levels of hypnotic prescribing, range from GBP2 million to GBP17 million per year. There are clear research needs in this area; in particular, none of the existing trials adequately compare these medications. It is suggested that further consideration should be given to a formal trial to allow head-to-head comparison of some of the key drugs in a double-blind RCT lasting at least 2 weeks, and of sufficient size to draw reasonable conclusions. We would also recommend that any such trial should include a placebo arm. It should also collect good-quality data around sleep outcomes and in particular quality of life and daytime drowsiness. We do not believe that any formal study of risk of dependency is feasible at present. Finally, the management of long-term insomnia is suggested for further investigation: considering the frequency of this symptom and its recurring course, the short-term trial of medication and lack of long-term follow-up undermine attempts to develop evidence-based guidelines for the use of hypnotics in this condition, or indeed for its whole management.

Adult↗

PubMed2004

Pegylated interferon alpha-2a and -2b in combination with ribavirin in the treatment of chronic hepatitis C: a systematic review and economic evaluation.

OBJECTIVES: To assess the clinical-effectiveness and cost-effectiveness of pegylated interferon-alpha combined with ribavirin in the treatment of chronic hepatitis C. DATA SOURCES: Electronic databases, reference lists of retrieved reports, and the industry submissions to the National Institute for Clinical Excellence. REVIEW METHODS: Sources were rigorously searched and studies were selected that met the inclusion criteria of being randomised controlled trials (RCTs) involving comparisons between pegylated interferon-alpha plus ribavirin and non-pegylated interferon plus ribavirin (two trials) or pegylated interferon alone and non-pegylated interferon alone (four trials). The primary outcome in all trials was sustained virological response (SVR) at follow-up. The trials were generally of good quality, although reporting of methodological details could have been more thorough in places. A cost-effectiveness model followed a hypothetical cohort of 1000 individuals with chronic hepatitis C over a 30-year period. RESULTS: In the two trials that tested pegylated interferon plus ribavirin against non-pegylated interferon plus ribavirin the combined percentage of sustained virological response was 55%. The relative risk (RR) for remaining infected was reduced by 17% for pegylated interferon plus ribavirin compared with non-pegylated interferon plus ribavirin. Response to therapy varied according to viral genotype. Patients with genotype 1 had the lowest levels of sustained virological response and patients with genotype 2 or 3 had the highest. In the four trials that evaluated pegylated interferon monotherapy against non-pegylated interferon the combined sustained virological response rates were 31% for pegylated interferon and 14% for non-pegylated interferon. The RR for remaining infected with hepatitis C was reduced by 20% with the use of pegylated interferon. Patients with genotype 1 had the lowest levels of sustained virological response. There were also variations in sustained virological response according to other prognostic variables such as baseline viral load. Regimens involving pegylated interferon appear to be fairly well tolerated. Adverse events were been reported, but they did not differ substantially from levels of adverse events in regimens involving non-pegylated interferon. The incremental discounted cost per QALY for comparing no active treatment to 48 weeks of dual therapy with pegylated interferon and ribavirin (PEG + RBV) was 6045 pounds sterling. When moving from 48 weeks of dual therapy with non-pegylated interferon and ribavirin (IFN + RBV) to 48 weeks of dual therapy with PEG + RBV the figure was 12,123 pounds sterling. Subgroup analyses for dual PEG + RBV therapy demonstrated that the most favourable incremental discounted cost per QALY estimates were for patients infected with genotypes 2 and 3, and with low baseline viral load (3921 pounds sterling) compared with no active treatment. Results of one-way sensitivity analyses showed that the estimates varied according to differences in SVRs, drug costs and discount rates. In general estimates remained under 30,000 pounds sterling per QALY. The incremental discounted cost per QALY when moving from no active treatment to 48 weeks of monotherapy with pegylated interferon was 6484 pounds sterling. When moving from 48 weeks of monotherapy with IFN to 48 weeks of monotherapy with PEG the figure was 8404 pounds sterling. As with dual therapy, the lowest incremental cost per QALY was for patients with genotypes 2 and 3 and low baseline viral load, in the range 2641-4194 pounds sterling. The highest estimates were for patients with genotype 1 and high baseline viral load, around 30,000 pounds sterling. CONCLUSIONS: Well-designed RCTs show that patients treated with pegylated interferon, both as dual therapy and as monotherapy, experience higher sustained viral response rates than those treated with non-pegylated interferon. Patients with genotypes 2 and 3 experience the highest response, with rates in excess of 80%. Patients with the harder to treat genotype 1 nevertheless benefit, with up to 46% of patients experiencing an SVR in one of the trials. Pegylated interferon also appears to be relatively cost-effective in both monotherapy and dual therapy, with cost per QALY estimates remaining generally under 30,000 pounds sterling. The most favourable estimates were for patients with genotypes 2 and 3. Pegylated interferon is a relatively new intervention in the treatment of hepatitis C and therefore there are areas where further research is needed. These include: efficacies of therapy with PEG-alpha-2a vs PEG-alpha-2b; retreatment of previous non-responders using pegylated interferon; efficacy of treatments and long-term outcomes in patients who have other co-morbidities; prospective tests of rules governing stopping treatment; treating patients with acute hepatitis C; problems that may occur in a minority of patients with hepatitis C, such as cryoglobulinaemia and vasculitis; additional psychological effects on quality of life due to hepatitis C and also on the treatment of children and adolescents with hepatitis C.

Antiviral Agents↗

PubMed2004

Clinical and cost-effectiveness of continuous subcutaneous insulin infusion for diabetes.

OBJECTIVES: To assess the clinical and cost-effectiveness of continuous subcutaneous insulin infusion (CSII) compared with multiple daily injections (MDI) in the delivery of intensive insulin therapy for the treatment of diabetes mellitus. DATA SOURCES: Electronic databases, references of retrieved articles and manufacturer submissions. Experts in the field were consulted. REVIEW METHODS: For the systematic review of clinical and cost-effectiveness, studies were assessed for inclusion according to predefined criteria by two reviewers. Data extraction and quality assessment were undertaken by one reviewer and checked by a second reviewer. Data on clinical effectiveness were synthesised through a narrative review with full tabulation of all eligible studies, with meta-analysis performed where appropriate. RESULTS: Twenty studies comparing CSII with MDI were identified. Quality was generally poor. In adults with Type 1 diabetes, glycated haemoglobin improved by 0.61% (95% CI -1.29 to 0.07) in longer term studies, although this improvement was smaller when a study using bovine ultralente was excluded. A reduction in insulin dose with CSII of about 12 units per day (-11.90, 95% CI -18.16 to 5.63) was found in short-term studies, with smaller differences in longer term studies. Body weight and cholesterol levels were similar between treatments. Hypoglycaemic events did not differ significantly between CSII and MDI in most trials, but some found fewer events with CSII and one found more hypoglycaemia and hypoglycaemic coma with CSII. There was no consistency between the studies in patient preference, but progress has been made both with insulin pumps and injector pens since the publication of many of the older studies. No difference in glycated haemoglobin between CSII and MDI was found in pregnancy; one study found less insulin was required by patients with CSII, but two other studies found no significant difference. One study of adolescents found lower glycated haemoglobin and insulin dose with CSII whereas a second study found no significant difference. In CSII analogue insulin was associated with lower glycated haemoglobin levels than soluble insulin. No economic evaluations comparing CSII with MDI were identified. The estimated additional cost of CSII compared to MDI varies from GBP1091 per annum to GBP1680 per annum, according to the make of the insulin pump and the estimated life of the device. These estimates include the costs for the insulin pump, the consumables associated with delivery of CSII, and an allowance for the initial education required when patients switch from MDI to CSII. The largest component of the annual cost for CSII is the cost of consumable items (e.g. infusion sets). CONCLUSIONS: When compared with optimised MDI, CSII results in a modest but worthwhile improvement in glycated haemoglobin in adults with Type 1 diabetes. It has not been possible to establish the longer term benefits of such a difference in glycated haemoglobin, although there is an expectation that it would be reflected in a reduction in long-term complications. More immediate primary benefits from CSII may be associated with an impact on the incidence of hypoglycaemic events and the dawn phenomenon, and greater flexibility of lifestyle. However, there is limited evidence on this, and information presented to offer context on quality-of-life is based on testimonies from those patients who have had a positive experience of CSII. The estimated cost to the NHS per year for CSII would be around GBP3.5 million in England and Wales if 1% of people with Type 1 diabetes used CSII, GBP10.5 million for 3%, and GBP17.5 million for 5%. Further research should focus on wider benefits of CSII, such as flexibility of lifestyle and quality of life, and on the psychological impact of wearing a device for 24 hours every day. Research into the use of CSII in children of different ages is also needed.

Cost-Benefit Analysis↗