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PubMed1987

Pregnancy outcome in cancer patients. Experience in a large cooperative group.

To evaluate the potential teratogenicity and mutagenicity of modern cancer treatment, the authors enumerated from a cooperative clinical trial group 133 pregnancies in 66 women with malignant neoplasms (53% with Hodgkin's disease, 26% with other lymphomas and leukemia, and 21% with solid tumors). The gestations were divided into the following groups: Group 1, 43 pregnancies ending before therapy; Group 2, therapy given at conception or during 32 pregnancies; and Group 3, 58 pregnancies after therapy. Although the total frequencies of abnormalities were similar in Groups 1 and 2 (23% of 35 pregnancies not electively aborted and 28% of 25, respectively), there were slightly more elective abortions and birth defects related to radiation exposure at a susceptible time of gestation in Group 2. Still, there were eight normal infants among the ten fetuses who were liveborn and had first trimester exposure to chemotherapy alone; so, drug therapy early in pregnancy is not inevitably teratogenic. The apparent and surprising excess of abnormal outcomes in Group 3, 40% of 50 pregnancies, was due to low birth weight and premature terminations of pregnancy, rather than an excess of congenital anomalies. The type of unfavorable outcomes in Group 3 and their concentration in the first year posttherapy suggested they could represent defects in factors (e.g., uterine or hormonal) that normally maintain gestations, and not genetic damage to oocytes. Limitations of the data, collected by mail from physicians and their patients, included biases of self-reporting and low statistical power. Prospective study, probably through interinstitutional collaboration, seems necessary, if accurate estimates are to be made of the frequency of certain outcomes, such as spontaneous abortion and minor anomalies.

Adolescent↗
PubMed1988

Cholecystectomy and adenomatous polyps of the colon in women.

The relationship between prior cholecystectomy and colon cancer in women has been a subject of recent research interest. No study has yet reported on cholecystectomy and adenomatous polyps, a precursor lesion for most colon cancers. This pilot case-control study interviewed 245 women who had undergone colonoscopy between 1983 and 1985 at Columbia-Presbyterian Medical Center with a structured telephone-administered questionnaire. Fifty-six were colon cancer cases, 105 were adenomatous polyp (AP) cases, and 84 were controls (without colonic neoplasia). Adjusted for age and educational attainment, the odds ratio for prior cholecystectomy among colon cancer cases compared to controls was 1.79 (95% confidence limits, 0.59 to 5.44) and 2.26 for right-sided colon cancer cases (95% confidence limits, 0.61 to 8.42). Despite a lack of statistical power, these estimates are consistent with earlier reports. The odds ratio for adenomatous polyp cases was 1.02 (95% confidence limits, 0.40 to 2.64), suggesting no association between prior cholecystectomy and adenomatous polyps. These preliminary findings are currently being explored in a large-scale case-control study.

Aged↗
PubMed1991

Screening for lung cancer. A critique of the Mayo Lung Project.

The National Cancer Institute of the United States recently sponsored three large-scale, randomized controlled trials of screening for early lung cancer. The trials were conducted at the Johns Hopkins Medical Institutions, the Memorial Sloan-Kettering Cancer Center, and the Mayo Clinic. Participants were middle-aged and older men who were chronic heavy cigarette smokers and thus at high risk of developing lung cancer. Screening procedures were chest radiography and sputum cytology, the only screening tests of established value for detecting early stage, asymptomatic lung cancer. In the Hopkins and Memorial trials the study population was offered yearly chest radiography plus sputum cytology every 4 months. The control population was offered yearly chest radiography only. In these trials the addition of sputum cytology appeared to confer no lung cancer mortality rate advantage. The Mayo Clinic trial compared offering chest radiography and sputum cytology every 4 months to offering advice that the two tests be obtained once a year. This trial demonstrated significantly increased lung cancer detection, resectability, and survivorship in the group offered screening every 4 months compared with the control group. However, there was no significant difference in lung cancer mortality rate between the two groups. The statistical power of these trials was somewhat limited. Nevertheless, results do not justify recommending large-scale radiologic or cytologic screening for early lung cancer at this time.

Clinical Trials as Topic↗
PubMed2001

The development of breast carcinoma in women with thyroid carcinoma.

BACKGROUND: Breast carcinoma and thyroid carcinoma are two malignancies that occur most commonly in women. An association between the incidence rates of thyroid and breast carcinoma in women after a diagnosis of the other malignancy has been suggested in a retrospective analysis of a single institution's tumor registry. In that study, an increased incidence of breast carcinoma in premenopausal women previously treated for thyroid carcinoma was observed. METHODS: The purpose of this study was to investigate further this relation utilizing a large database, the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) database. The SEER database is maintained by the National Cancer Institute, and it represents 11 population-based cancer registries covering approximately 14% of the United States population. The study was a population-based retrospective cohort analysis using external comparisons. From 1973 to 1994, 365 women in the SEER database were identified as having both thyroid and breast carcinomas. The SEER database from 1973 to 1994 was utilized to calculate age specific and calendar year specific incidence rates for each year for thyroid and breast carcinomas. The expected number of second cancers for each age group, calendar year, and follow-up period were determined by multiplying these incidence rates by the age specific and calendar year specific number of person-years at risk. The risk ratio (RR) was calculated by dividing the observed by the expected number of second cancers. Statistical significance was determined by the Poisson test. RESULTS: A total of 1,333,115 person-years were available for analysis. One hundred thirteen thyroid carcinoma cases were diagnosed after breast carcinoma cases (RR, 0.99; P = 0.576). Two hundred fifty-two breast carcinoma cases were diagnosed after thyroid carcinoma cases (RR, 1.18; P = 0.007). Premenopausal women (age 20-49 years) with an index thyroid carcinoma have a significantly increased risk of developing subsequent breast carcinoma (RR, 1.42; P = 0.001). Black premenopausal women with an index thyroid carcinoma do not have an increased risk of developing breast carcinoma, but the statistical power is lower due to low numbers. No women with index breast carcinoma have an increased risk of developing thyroid carcinoma. CONCLUSIONS: Women with a history of thyroid carcinoma have a greater than expected risk of developing breast carcinoma. This risk is most pronounced in premenopausal white women. The implications of this observation with respect to breast carcinoma screening guidelines and thyroid carcinoma treatment guidelines deserve further investigation.

Adult↗
PubMed2000

Cancer risk in laboratory workers: an emphasis on biological research.

BACKGROUND: At the end of the 1980s, several cancer clusters were observed in biological research laboratories. Over time, biological research and the technologies used have been diverse and have involved a wide range of mutagenic or carcinogenic chemical, physical and biological agents. METHODS: We reviewed 45 published studies on cancer risk among biological research personnel and workers in closely related fields, and numerous reports based on routinely collected data. RESULTS: Biological research could be associated with an elevated risk for pancreatic cancer, brain tumors, and certain hemopathies. A common limitation of available studies was low statistical power and the absence or inaccuracy of data on individual past exposure. CONCLUSIONS: Overall, this study suggests a low overall risk of cancer, albeit a higher risk may be suggested for cancers of the pancreas (risk ratios ranging from 0.5 to 6.3) and brain (0.7-9.4), and for non-Hodgkin's lymphoma (0.6-51.5). We suggest ways in which multiple past exposures could be assessed more precisely and emphasize a pressing need to take into account known confounders.

Biological Science Disciplines↗
PubMed1983

A conjoint measurement analysis of clinical predictions.

A lack of impressive theories in clinical psychology has been attributed to an excessive reliance on significance testing. Conjoint measurement is a worthwhile alternative to significance testing. Conjoint measurement determines whether data obey the ordinal properties of a model that contains main effect terms, interaction terms, or a combination of the two. Unlike hypothesis testing, with conjoint measurement an increase in statistical power leads to a greater risk of refuting a theory. In this study, conjoint measurement was used to describe how systems-oriented therapists predict the occurrence of suicide. Although the systems approach emphasizes the interaction between an individual and a system, all 10 clinicians were described by an additive model.

Humans↗
PubMed2000

Combined linkage and linkage disequilibrium mapping for genome screens.

Linkage analysis and association studies, two major approaches for genetic studies of human diseases, are useful for mapping genes that are highly penetrant, but both use only part of the information that is available for mapping disease genes. Therefore, they provide limited utility when used alone. In this report, we present combined linkage and linkage disequilibrium mapping that simultaneously utilizes linkage and linkage disequilibrium information for mapping human disease genes. Compared with the existing linkage analysis and association study methods, this method has several advantages: 1) it has high statistical power by a joint analysis of linkage and linkage disequilibrium for localizing disease susceptibility loci: 2) it unifies the theory of linkage analysis and linkage disequilibrium mapping, 3) it retains the general framework for linkage analysis and, hence, can be easily incorporated into the existing software for the linkage analysis. The proposed LLDM is applied to familial hemophagocytic lymphohistiocytosis (FHL) disease.

Chromosome Mapping↗
PubMed2000

N-acetyl transferase-2 and bladder cancer risk: a meta-analysis.

Interindividual differences in bladder cancer susceptibility may be partly mediated through polymorphic variability in the metabolism of carcinogens. N-acetyl transferase-2 (NAT2) has been extensively studied as a risk factor in this context, but the results are inconsistent. In some studies the failure to demonstrate a relationship may be a consequence of a lack of statistical power. To overcome lack of power, data from 21 published case-control studies were pooled in a meta-analysis using a random-effects model. The pooled odds ratio of bladder cancer associated with slow acetylator status was 1.31 (95% CI: 1.11-1.55). The results suggest that NAT2 slow acetylator status is associated with a modest increase in risk of bladder cancer. There was, however, heterogeneity between studies. It is clear from this overview that greater attention should be paid to the design of these types of study.

Arylamine N-Acetyltransferase↗
PubMed2000

Haemodilution for acute ischaemic stroke.

BACKGROUND: Ischaemic stroke interrupts the flow of blood to part of the brain. Haemodilution is thought to improve the flow of blood to the affected areas of the brain. OBJECTIVES: The objective of this review was to assess the effects of haemodilution in acute ischaemic stroke. SEARCH STRATEGY: We searched the Cochrane Stroke Group trials register, Medline and conference abstracts. We contacted manufactures and investigators in the field. SELECTION CRITERIA: Randomised trials of haemodilution treatment in people with acute ischaemic stroke. Only trials where treatment was started within 72 hours of stroke onset were included. DATA COLLECTION AND ANALYSIS: Two reviewers assessed trial quality and independently extracted the data. MAIN RESULTS: Sixteen trials were included. A combination of venesection and plasma volume expander was used in eight trials. Eight trials used plasma volume expander alone. The plasma volume expander was dextran 40 in 11 trials, hydroxyethyl starch in four trials and albumin in one trial. Two trials tested haemodilution in combination with another therapy. Evaluation was blinded in 11 trials. Five trials probably included some patients with intracerebral haemorrhage. Haemodilution did not significantly reduce deaths within seven to 28 days (odds ratio 1.12, 95% confidence interval 0.88 to 1.43). Similarly, haemodilution did not influence deaths within three to six months (odds ratio 1.02, 95% confidence interval 0.85 to 1.23), or death and dependency or institutionalisation (odds ratio 1.01, 95% confidence interval 0.86 to 1.19). The results were similar in confounded and unconfounded trials, in trials of isovolaemic and hypervolaemic haemodilution, and in trials using different types of hemodiluting agents. Six trials reported venous thromboembolic events. There was a tendency towards reduction in deep venous thrombosis and/or pulmonary embolism at three to six months follow-up (odds ratio 0.59, 95% confidence interval 0.33 to 1.06). REVIEWER'S CONCLUSIONS: The overall results of this review are compatible both with a modest benefit and a moderate harm of haemodilution therapy for acute ischaemic stroke. As used in the randomised trials, this therapy has not been proven to improve survival or functional outcome.

Brain Ischemia↗
PubMed2001

Pharmacological treatment for aphasia following stroke.

BACKGROUND: Aphasia describes language impairment associated with a brain lesion. OBJECTIVES: The objective of this review was to assess the effects of drugs on language abilities when given to people with aphasia following stroke. SEARCH STRATEGY: We searched the Cochrane Stroke Group Register (last searched: May 2001), and reference lists of relevant articles to December 1998. We also contacted academic institutions and other researchers to identify further published and unpublished trials. MEDLINE was searched from 1966-1998, and CINAHL from 1982-1998. We searched the International Journal of Disorders of Communication by hand (known by other names in the past), from 1969 to 1998. SELECTION CRITERIA: Randomised controlled trials comparing: ~bullet~Any drug given to improve language, versus no treatment, or versus placebo ~bullet~Any drug given to improve language versus speech and language therapy ~bullet~One drug given to improve language versus another drug given with the same aim DATA COLLECTION AND ANALYSIS: The principal reviewer collected the data, and assessed the quality of the trials with independent data checking and methodological advice. If we could not perform a statistical combination of different studies, we sought missing data. Failing that we provided a description. We sought missing data from authors, or where appropriate, a drug company. MAIN RESULTS: We considered fifty two studies in detail, from which we identified ten trials suitable for the review. In most cases the methodological quality was unassessable, and only one trial reported sufficient detail for us to complete a description and analysis. This study did lose a large number of patients during its course. Drugs used in the trials identified were piracetam, bifemalane, piribedil, bromocriptine, idebenone, and Dextran 40. We found weak evidence that patients were more likely to have improved on any language measure at the end of the trial if they had received treatment with piracetam (odds ratio 0.46, 95% confidence interval 0.3 to 0.7). The evidence is considered weak because of the large numbers of drop outs from the trials identified, who were lost to follow up. Patients who were treated with piracetam were no more likely (considering statistical significance) than those who took a placebo to experience unwanted effects, including death (odds ratio 1.29, 95% confidence interval for difference 0.9 to 1.7). However, the differences in death rates between the two groups, even though not not statistically significant, do give rise to some concerns that there may be an increased risk of death from taking piracetam. We could not determine if drug treatment is more effective than speech and language therapy. We could not determine whether one drug is more effective than another. REVIEWER'S CONCLUSIONS: The main conclusion of this review is that drug treatment with piracetam may be effective in the treatment of aphasia after stroke. Further research is needed to explore the effects of drugs for aphasia, in particular piracetam. If a trial is done, this must be large enough to have adequate statistical power. The safety of the drug should be of primary interest. Researchers should examine the long term effects of this treatment, and whether it is more effective than speech and language therapy.

Aphasia↗
PubMed2000

Speech and language therapy for aphasia following stroke.

BACKGROUND: Aphasia describes language impairment associated with a brain lesion. OBJECTIVES: The objective of this review was to assess the effects of formal speech and language therapy and non-professional types of support from untrained providers for people with aphasia after stroke. SEARCH STRATEGY: We searched the Cochrane Stroke Group Trials Register (last searched: March 1999), and reference lists of relevant articles to December 1998. We also contacted academic institutions and other researchers to identify further published and unpublished trials. We searched The International Journal of Disorders of Communication by hand (known by other names in the past), from 1969 to 1998. Date of most recent searches: January 1999. SELECTION CRITERIA: Randomised controlled trials comparing: 1. Any type of formal speech and language therapy in any setting administered by trained speech and language therapists versus no treatment. 2. Any type of formal speech and language therapy in any setting administered by trained speech and language therapists versus any type of informal support for aphasia, given by speech and language therapists or volunteers, whether these were trained or untrained. 3. One type of speech and language therapy versus another type. Outcome measures included measures of any type of communication, other measures of functioning, numbers of drop-outs, and other non-clinical outcomes. DATA COLLECTION AND ANALYSIS: The principal reviewer collected the data, and assessed the quality of the trials with independent data checking and methodological advice. If we could not perform a statistical combination of different studies, we sought missing data. Failing that we provided a description. MAIN RESULTS: We considered sixty studies in detail, from which we identified twelve trials suitable for the review. Most of these trials were relatively old with poor or unassessable methodological quality. None of the trials was detailed enough for us to complete description and analysis. We could not determine whether formal speech and language therapy is more effective than informal support. REVIEWER'S CONCLUSIONS: The main conclusion of this review is that speech and language therapy treatment for people with aphasia after a stroke has not been shown either to be clearly effective or clearly ineffective within a RCT. Decisions about the management of patients must therefore be based on other forms of evidence. Further research is required to find out if effectiveness of speech and language therapy for aphasic patients is effective. If researchers choose to do a trial, this must be large enough to have adequate statistical power, and be clearly reported.

Aphasia↗
PubMed2000

Oral 5-aminosalicylic acid for inducing remission in ulcerative colitis.

OBJECTIVES: To assess the efficacy, dose-responsiveness and safety of the newer release formulations of 5-aminosalicylic acid (5-ASA) compared to placebo or sulfasalazine (SASP) for the induction of remission in active ulcerative colitis. SEARCH STRATEGY: A computer-assisted literature search for relevant studies (1981-1998) was performed using MEDLINE, BIOS, the Cochrane Controlled Trials Register and the Science Citation Index, followed by a manual search of reference lists from previously retrieved articles, review articles, symposia proceedings, and abstracts from major gastrointestinal conferences. SELECTION CRITERIA: Studies were accepted for analysis if they were randomized, double-blinded, and controlled clinical trials of parallel design, with treatment durations of a minimum of four weeks. DATA COLLECTION AND ANALYSIS: Based on an intention to treat principle, the outcomes of interest in the treatment of active disease were the failure to induce global/clinical remission, global/clinical improvement, endoscopic remission, or endoscopic improvement. MAIN RESULTS: 5-ASA was superior to placebo with regard to all measured outcome variables. For the failure to induce global/clinical improvement or remission, the pooled Peto odds ratio was 0.51 (95% CI, 0.35 to 0.76). A dose-response trend for 5-ASA was also observed. When 5-ASA was compared to SASP, the pooled Peto odds ratio was 0.87 (CI, 0.63 to 1.21) for the failure to induce global/clinical improvement or remission, and 0.66 (CI, 0.42 to 1.04) for the failure to induce endoscopic improvement. SASP was not as well tolerated as 5-ASA. REVIEWER'S CONCLUSIONS: The newer 5-ASA preparations were superior to placebo and tended towards therapeutic benefit over SASP. However, considering their relative costs, a clinical advantage to using the newer 5-ASA preparations in place of SASP appears unlikely.

Aminosalicylic Acids↗
PubMed2006

Oral 5-aminosalicylic acid for induction of remission in ulcerative colitis.

BACKGROUND: The newer 5-ASA preparations were intended to avoid the adverse effects of SASP while maintaining its therapeutic benefits. The efficacy and safety of 5-ASA preparations have been evaluated in numerous clinical trials that have often lacked sufficient statistical power to arrive at definitive conclusions. Previously, it was found that newer 5-ASA drugs in doses of at least 2 g/day, were more effective than placebo but no more effective than SASP in inducing remission in ulcerative colitis. This updated review includes more recent studies and evaluates the effectiveness, dose-responsiveness, and safety of 5-ASA preparations in terms of more precise outcome measures. OBJECTIVES: To assess the efficacy, dose-responsiveness and safety of the newer release formulations of 5-aminosalicylic acid (5-ASA) compared to placebo or sulfasalazine (SASP) for the induction of remission in active ulcerative colitis. SEARCH STRATEGY: A computer-assisted literature search for relevant studies (1981-2005) was performed using MEDLINE, BIOS, the Cochrane Controlled Trials Register, the Cochrane IBD/FBD group specialized trials register and the Science Citation Index, followed by a manual search of reference lists from previously retrieved articles, review articles, symposia proceedings, and abstracts from major gastrointestinal conferences. SELECTION CRITERIA: Studies were accepted for analysis if they were randomized, double-blinded, and controlled clinical trials of parallel design, with treatment durations of a minimum of four weeks. DATA COLLECTION AND ANALYSIS: Based on an intention to treat principle, the outcomes of interest in the treatment of active disease were the failure to induce global/clinical remission, global/clinical improvement, endoscopic remission, or endoscopic improvement. MAIN RESULTS: 5-ASA was superior to placebo with regard to all measured outcome variables. For the failure to induce global/clinical improvement or remission, the pooled Peto odds ratio was 0.40 (95% CI, 0.30 to 0.53). A dose-response trend for 5-ASA was also observed. When 5-ASA was compared to SASP, the pooled Peto odds ratio was 0.83 (95% CI 0.60 to 1.13) for the failure to induce global/clinical improvement or remission, and 0.66 (95% CI 0.42 to 1.04) for the failure to induce endoscopic improvement. SASP was not as well tolerated as 5-ASA. AUTHORS' CONCLUSIONS: The newer 5-ASA preparations were superior to placebo and tended towards therapeutic benefit over SASP. However, considering their relative costs, a clinical advantage to using the newer 5-ASA preparations in place of SASP appears unlikely. This review updates the existing review of oral 5-aminosalicylic acid for induction of remission in ulcerative colitis which was published in the Cochrane Library (Issue 1, 2006).

Administration, Oral↗
PubMed2000

Patient education for mechanical neck disorders.

BACKGROUND: To track down the best estimate of efficacy of the various conservative management strategies for mechanical neck disorders, a four-part systematic review was prepared. Part four investigates the efficacy of patient education strategies as the therapeutic intervention. OBJECTIVES: This review of patient education is one of four reviews of conservative management of mechanical neck disorders. The other reviews address manual, physical and drug therapies. The objective of this review was to assess the effects of patient education for pain in adults with mechanical neck disorders. SEARCH STRATEGY: We searched Medline, Embase, Chirolars, Index to Chiropractic Literature, Cinahl, Science Citation Index, Conference Proceedings Index, National Technical Information Services from 1985 to December 1993, reference lists of the retrieved articles and we contacted experts in the field. SELECTION CRITERIA: Randomised trials or controlled clinical trials of patient educational strategies for adults with mechanical neck disorders. DATA COLLECTION AND ANALYSIS: Three reviewers independently assessed trial quality and two reviewers independently extracted data. Investigators were contacted to obtain data that could not be found in the published reports. MAIN RESULTS: Three trials were included. Their methodological quality varied from weak to strong. One trial did not find a significant reduction in pain using group instructional strategies (neck school) and exercise with or without psychological counselling compared to no treatment (standardised mean difference 0.07, 95% confidence interval -0.51 to 0.66, and -0.37, 95% confidence interval -0.95 to 0.22, respectively). Another trial did not find a significant reduction in pain using individualised patient education (advice), anti-inflammatories and analgesics compared with placebo (standardised mean difference 0.24, 95% confidence interval -0.58 to 1.07). The third trial found that advice which included demonstrated mobilization exercises, verbal and written instruction on posture correction, the use of a collar, heat sources, muscle relaxation and analgesics gave significant pain relief compared with general advice about mobilisation after a period of rest and use of analgesics at 4 weeks of treatment (standardised mean difference -0.62, 95% confidence interval -1.05 to -0.19) but at 6 weeks of treatment there was no longer any difference (s.m.d. -0.37, 95% confidence interval -0.8 to 0.05). The first two trials lacked statistical power and the third was methodologically weak. REVIEWER'S CONCLUSIONS: Patient education utilising individualised or group instructional strategies has not been shown to be beneficial in reducing pain for mechanical neck disorders.

Adult↗
PubMed2000

Newer atypical antipsychotic medication versus clozapine for schizophrenia.

BACKGROUND: Clozapine is an atypical antipsychotic drug, which is claimed to have superior efficacy and to cause fewer movement disorders. However, clozapine carries a significant risk of serious blood disorders. Newer atypical antipsychotics are safer alternatives that might share the benefits of clozapine. It is thus of interest to compare the effectiveness of newer atypical antipsychotics with the effectiveness of clozapine. OBJECTIVES: To evaluate the clinical effects of newer atypical antipsychotic drugs in comparison to clozapine for schizophrenia. SEARCH STRATEGY: Publications in all languages were searched from the following databases: Biological Abstracts/BIOSIS (1980-1999), The Cochrane Schizophrenia Group's Register of Trials (1998), The Cochrane Library CENTRAL Register (Issue 4, 1999), EMBASE (1980-1998), MEDLINE (1966-1999), LILACS/CD-ROM (1998), and PsycLIT/PsycINFO (1974-1999). Trials were also sought from recent conference proceedings and reference lists of included papers. Authors of recent trials and the manufacturers of clozapine, iloperidone, olanzapine, quetiapine, remoxipride, risperidone, sertindole, ziprasidone and zotepine were contacted. SELECTION CRITERIA: All randomised controlled trials comparing clozapine with newer atypical antipsychotic drugs were included by independent assessment by two reviewers. DATA COLLECTION AND ANALYSIS: Data were extracted independently by two reviewers. Relative risks (RR) and 95% confidence intervals (CI) of homogenous dichotomous data were calculated. A random effects model was used for heterogeneous dichotomous data. Where possible the number needed to treat (NNT) statistic with 95%CI were also calculated. Weighted or standardised means were calculated for continuous data. Due to the small number of included studies, sensitivity analyses or funnel plot statistics were not undertaken for this version of the review. MAIN RESULTS: The current review includes eight studies (22 papers), of which three studies are 4-6 weeks in duration and only one study is of more than 12 weeks' duration. Newer atypical drugs seemed to be broadly similar to clozapine using a clinical global index or trialists' definitions of improvement, but this result was obtained from a relatively small number of studies. Due to the small number of studies and patients, wide confidence intervals were seen when their effectiveness as measured by symptom rating scales was compared. Social functioning was better in patients on newer atypical medication (risperidone) than in those on clozapine, but this finding is based on a single underpowered trial and has to be interpreted with caution. Clozapine and newer atypical drugs showed their adverse effect profile to be dissimilar: while clozapine produced more fatigue, hypersalivation, nausea, and orthostatic dizziness, new atypical drugs, with the exception of olanzapine, produced more extrapyramidal symptoms. The impact of these drugs and their effects on patients' day-to-day quality of life, service use, hospital admission, and pharmacoeconomics was not measured. REVIEWER'S CONCLUSIONS: The equal effectiveness and tolerability of new atypical drugs in comparison with clozapine is not yet demonstrated. Lack of statistical power to determine the comparative efficacy and effectiveness of newer atypical drugs makes it difficult to judge whether newer drugs are more effective, less effective or equivalent. Trials of sufficient power, with longer duration, measuring clinically important outcomes, are needed to assess the true comparative clinical effectiveness, tolerability and cost effectiveness of newer drugs in relation to clozapine.

Antipsychotic Agents↗
PubMed2004

Prostanoids for intermittent claudication.

BACKGROUND: Peripheral arterial occlusive disease (PAOD) is a common cause of morbidity in the general population. While numerous studies have established the efficacy of prostanoids in PAOD stages III and IV the question of the role of prostanoids as an alternative or additive treatment in patients suffering from claudicatio intermittens (PAOD II) has not yet been clearly answered. OBJECTIVES: The aim of this review was to evaluate effects of prostanoids in patients with intermittent claudication. SEARCH STRATEGY: Computerised searches of the Cochrane Peripheral Vascular Diseases Specialised Register (last searched April 2003), The Cochrane Central Register of Controlled Trials (CENTRAL) (last searched Issue 1, 2003), MEDLINE and EMBASE were undertaken. In addition relevant journals were hand-searched. SELECTION CRITERIA: Randomized clinical trials describing the effects of prostanoids in the treatment of patients suffering from intermittent claudication have been considered for inclusion. DATA COLLECTION AND ANALYSIS: All reviewers assessed the quality of studies and extracted data unblinded. Statistical analysis including tests for heterogeneity and overall effect were performed by using MetaView of Review Manager 4.2. All numeric values are expressed as mean +/- Standard deviation (SD). MAIN RESULTS: Eighteen studies were included for analysis. A significant heterogeneity between the included studies was detected in most of the subgroup analysis. Five studies compared the effects of prostaglandin E1 (PGE1) versus placebo, and reported in their individual results significant increases in walking distances after the administration of PGE1. The attained increase in walking distances appears to be not merely a short-term effect because several studies reported that walking capacity remained increased even after termination of treatment. On the other hand, oral or intravenous prostacyclin did not increase the walking distances significantly. At least one adverse reaction was reported from 23.6% of the patients treated with prostacyclin (PGI2), and its analogues and from 13.7% of the patients treated with PGE1. REVIEWER'S CONCLUSIONS: Because of the heterogeneity between most of the included studies, we did not pool relevant parts of the data by meta-analysis. Based on the individual results of the published literature, patients with intermittent claudication seem to benefit from administration (intravenous or intra-arterial) of PGE1 by a significant improvement of their walking capacity. Further well-conducted randomized, double blinded trials, with a sufficient number of patients to provide statistical powerful information, should be performed to confirm the results of this review.

Alprostadil↗
PubMed2004

Prophylactic anastomotic drainage for colorectal surgery.

BACKGROUND: There is little agreement on prophylactic use of drains in anastomoses in elective colorectal surgery despite many randomized clinical trials. Results of these trials are contradictory, quality and statistical power of these individual studies have been questioned. Once anastomotic leakage has occurred it is generally agreed that drains should be used for therapeutic purposes. However, on prophylactic use no such agreement exists. OBJECTIVES: Comparison of safety and effectiveness of routine drainage and non-drainage regimes after colorectal surgery. The following hypothesis was tested: The use of prophylactic anastomotic drainage after elective colorectal surgery does not prevent development of complications. SEARCH STRATEGY: The studies were identified from CINAHL, EMBASE, LILACS, MEDLINE, Controlled Clinical Trials Database, Trials Register of the Cochrane Colorectal Cancer Group, reference lists. SELECTION CRITERIA: Randomized controlled trials comparing drainage with non-drainage regimes after anastomoses in elective colorectal surgery were reviewed. Outcome measures were: 1. mortality; 2. clinical anastomotic dehiscence; 3. radiological anastomotic dehiscence; 4. wound infection; 5. reoperation; 6. extra-abdominal complications. DATA COLLECTION AND ANALYSIS: Data were independently extracted and cross-checked by the two reviewers. The methodological quality of each trial was assessed. Details of the randomization (generation and concealment), blinding, and the number of patients lost to follow-up were recorded. The RCTs were stratified based on experimental group, according to clinical homogeneity (external validity). MAIN RESULTS: Of the 1140 patients enrolled (6 RCTs), 573 were allocated for drainage and 567 for no drainage. The patients assigned to the drainage group compared with the ones assigned to non-drainage group showed: a) Mortality: 3% (18 of 573 patients) compared with 4% (25 of 567 patients); b) Clinical anastomotic dehiscence: 2% (11 of 522 patients) compared with 1% (7 of 519 patients); c) Radiological anastomotic dehiscence: 3% (16 of 522 patients) compared with 4% (19 of 519 patients); d) Wound infection: 5% (29 of 573 patients) compared with 5% (28 of 567 patients); e) Reintervention: 6% (34 of 542 patients) compared with 5% (28 of 539 patients); f) Extra abdominal complications: 7% (34 of 522 patients) compared with 6% (32 of 519 patients). REVIEWERS' CONCLUSIONS: There is insufficient evidence showing that routine drainage after colorectal anastomoses prevents anastomotic and other complications.

Anastomosis, Surgical↗
PubMed2002

Ursodeoxycholic acid and/or antibiotics for prevention of biliary stent occlusion.

BACKGROUND: Malignant biliary obstruction, which requires endoscopic stenting as palliative therapy, is often complicated by clogging of the stent with subsequent jaundice and/or cholangitis. Stent clogging may be caused by microbiological adhesion and biliary stasis. Therefore, antibiotics and choleretic agents like ursodeoxycholic acid (UDCA) have been investigated to see whether they prolong stent patency. OBJECTIVES: To evaluate if UDCA and/or antibiotics may prolong stent patency and survival in patients with strictures of the biliary tract and endoscopically inserted stents. SEARCH STRATEGY: The Trials Register of The Cochrane Hepato-Biliary Group, The Cochrane Library, MEDLINE, Current Contents, EMBASE, and CancerLit were searched until June 2001. Reference lists of the identified articles were checked for further trials. SELECTION CRITERIA: All randomised or quasi-randomised clinical trials investigating UDCA and/or antibiotics in patients with biliary stents were considered for inclusion, regardless of blinding, language, and publication status. DATA COLLECTION AND ANALYSIS: Trial inclusion, quality assessment, and data extraction were performed independently by two reviewers. Principal investigators were contacted for further information. Survival data were combined by using hazard ratios (with 95% confidence interval (95% CI)). MAIN RESULTS: Five non-blinded randomised trials with 258 patients with malignant strictures treated with polyethylene stents were included. Three trials, including 152 patients, investigated a combination of UDCA and antibiotics versus no treatment. The meta-analysis of these three trials does not show a significant treatment effect on the duration of stent patency (hazard ratio (random effects model) 0.58, 95% CI 0.22 to 1.54) or mortality (hazard ratio (fixed effect model) 0.99, 95% CI 0.68 to 1.43). Two trials with 106 patients compared antibiotics with no treatment, one of these trials used a combination of antibiotics and rowachol (an 'alternative' drug of the 'mint' family). The pooled results of these two trials do not show significant effects of antibiotics on the duration of stent patency (hazard ratio (fixed effect model) 0.69 (95% CI 0.37 to 1.30)) or mortality (hazard ratio (fixed effect model) 1.23 (95% CI 0.72 to 2.08). Data concerning duration of hospital stay, frequency of cholangitis, and rate of infectious complications due to selection of antibiotic resistant bacteria strains were not available. REVIEWER'S CONCLUSIONS: Treatment with UDCA and/or antibiotics to prevent clogging of biliary stents in patients with malignant stricture of the biliary tract cannot be recommended routinely on the basis of the existing randomised clinical trials. Further trials are needed with rigorous methodology and sufficient statistical power.

Anti-Bacterial Agents↗