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Corrado Barbui

Publications and source records attributed to Corrado Barbui.

At least 37 records · Page 2Linked to original sources
PubMed2006

Validity of the impact factor of journals as a measure of randomized controlled trial quality.

OBJECTIVE: To assess whether the impact factor, a measure of the frequency with which journal articles are cited in the scientific literature, is a proxy measure of the quality of articles reporting the results of randomized controlled trials. METHOD: The quality of trials included in an ongoing Cochrane review concerned with the antidepressant fluoxetine was assessed using the Cochrane Collaboration Depression, Anxiety, and Neurosis quality assessment instrument, the Jadad scale, and the quality criterion of the Cochrane Collaboration Handbook. Journal impact factors were extracted from the Journal Citation Report. RESULTS: A total of 131 articles reported results from 132 clinical trials comparing fluoxetine with other antidepressants. The relationship between trial quality and the impact factor of journals where these studies were published, stratified by period of publication, revealed that journals with impact factors above 4 points published only trials with above-average overall quality ratings, while journals with impact factors below 4 points published both high- and low-quality trials. The Jadad scale revealed similar quality in trials published in journals with high, medium, and low impact factors (Pearson chi(2) = 0.298, p = .861), and the quality criterion of the Cochrane Collaboration Handbook showed unclear randomization in the majority of trials and in all 15 trials published in high-impact factor journals (Pearson chi(2) = 4.678, p = .096). CONCLUSION: The impact factor of journals is not a valid measure of randomized controlled trial quality.

Bibliometrics↗
PubMed2006

Are all antidepressants really the same? The case of fluoxetine: a systematic review.

OBJECTIVE: To systematically review the efficacy and tolerability of fluoxetine, the most widely studied of newer antidepressants, in comparison with all other antidepressants in the acute treatment of depression in patients aged more than 18 years. DATA SOURCES: Studies were identified through electronic searches of the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register and the Cochrane Central Register of Controlled Trials up to March 2004. The terms FLUOXETIN* OR adofen or docutrix or erocap or fluctin or fluctine or fluoxeren or fontex or ladose or lorien or lovan or mutan or prozac or prozyn or reneuron or sanzur or saurat or zactin were used. MEDLINE (1966-2004) and EMBASE (1974-2004) were searched using fluoxetine and randomized controlled trial or random allocation or double-blind method. No language restrictions were applied. Reference lists of relevant papers and previous systematic reviews were hand-searched for published reports up to March 2004. STUDY SELECTION: Only randomized controlled trials (either blind or nonblind) were included. DATA SYNTHESIS: 131 randomized controlled trials were eligible. A p value less than .01 was chosen to test the null hypothesis, and a 99% confidence interval was calculated to detect statistically significant differences with a high degree of confidence. Fixed- and random-effects relative risks, odds ratios (ORs), and Peto ORs were routinely calculated for each outcome measure. In terms of efficacy, we found a statistically significant difference favoring sertraline and venlafaxine over fluoxetine. In terms of tolerability, patients allocated to fluoxetine were less likely to leave the study early only in comparison with those allocated to amitriptyline and pramipexole. CONCLUSIONS: This systematic review highlighted that there are differences between fluoxetine and specific comparator antidepressants. Several of the differences met a prespecified criterion for clinical significance. The statistical approach adopted in this systematic review could represent a useful tool for putting clinical trial data into practice.

Adult↗
PubMed2005

Health status, resource consumption, and costs of dysthymia. A multi-center two-year longitudinal study.

BACKGROUND: In this study we estimated the health status, resource consumption and costs of a large cohort of patients with early and late-onset dysthymia. METHODS: The DYSCO (DYSthymia COsts) project is a multi-center observational study which prospectively followed for two years a randomly chosen sample of patients with dysthymia in the Italian primary health care system. RESULTS: A total of 501 patients were followed for two years; 81% had early-onset dysthymic disorder. During the study, improvement was seen in most domains of the 36-Item Short Form Health Survey (SF-36) questionnaire. Comparison of the SF-36 scores for the two groups showed that only the physical health index significantly differed during the two years. The use of outpatient consultations, laboratory tests and diagnostic procedures was similar in the two groups, but patients with early-onset dysthymia were admitted significantly more than late-onset cases. Hospital admissions were almost entirely responsible for the higher total cost per patient per year of early-onset dysthymia. LIMITATIONS: A first limitation of this study is that general practitioners were selected on the basis of their willingness to participate, not at random; secondly, no information was collected on concomitant psychiatric comorbidities. CONCLUSIONS: The present study provides the first prospective, long-term data on service use and costs in patients with dysthymia. Differently from patients with early-onset dysthymia, patients with late-onset dysthymia were admitted less and cost less.

Adult↗
PubMed2005

Investigation of corpus callosum in schizophrenia with diffusion imaging.

BACKGROUND: Corpus callosum (CC) is the main white matter commissure between the two cerebral hemispheres. Abnormalities of CC have been shown in schizophrenia patients by magnetic resonance imaging (MRI) studies. We here further investigated CC organization with diffusion imaging (DWI) in a sample of schizophrenia patients recruited from the epidemiologically defined catchment area of South Verona, Italy. METHODS: Sixty-seven patients with schizophrenia and 70 normal controls were studied. Regions of interests (ROIs), standardized at 5 pixels, were placed in CC on the non-diffusion weighted echoplanar images (b = 0) and were then automatically transferred to the corresponding maps to obtain the apparent diffusion coefficient (ADC) of water molecules. RESULTS: ADC measures for all callosal subregions in schizophrenia patients were significantly greater compared to normal controls (ANCOVA, p < 0.05). Positive symptoms significantly correlated with anterior callosal ADC measures (partial correlation analyses, p < 0.05). CONCLUSIONS: These findings support the existence of widespread microstructure disruption of CC in schizophrenia, which may ultimately lead to inter-hemispheric misconnection, and also suggest a specific role of anterior transcallosal disconnectivity in underlying positive symptoms. Future longitudinal MRI studies in high risk and first-episode patients together with neurophysiological tests are indicated to further examine CC anatomical abnormalities and inter-hemispheric transmission in schizophrenia.

Adult↗
PubMed2005

Antidepressant drug prescribing among elderly subjects: a population-based study.

BACKGROUND: The patterns of antidepressant drug prescribing have rarely been studied in large and geographically defined populations of elderly subjects. In the present study we examined the prevalence and distribution of antidepressant prescribing in Lombardy, a northern Italy region with more than one and a half million elderly inhabitants. METHODS: We used the Regional Administrative Database of Lombardy. This database includes all prescriptions reimbursed by the National Health System in the population living in this region. All antidepressant prescriptions dispensed to subjects aged 65 years or above during 2001 were extracted and prevalence data calculated by dividing antidepressant users by the total number of male and female residents in each age group. RESULTS: During the 12 months surveyed 153,706 subjects were dispensed one or more prescriptions of antidepressants, yielding a prevalence of use of 9.49 subjects per 100 inhabitants (95% confidence interval 9.44, 9.53). Although the proportion of chronic users slightly decreased with age, more than 35% of those older that 85 years were moderate or chronic antidepressant users. General practitioners issued the majority of antidepressant prescriptions, and most antidepressant users were also dispensed agents for medical disorders. CONCLUSIONS: The very high rates of antidepressant drug prescribing detected in late life suggest the need of characterising these subjects in terms of medical and psychiatric characteristics, needs and quality of life. It also suggests the need for pragmatic clinical trials, carried out in the general practice, with the aim of assessing whether antidepressants are effective in these conditions.

Aged↗
PubMed2005

Development of a registry for monitoring psychotropic drug prescriptions: aims, methods and implications for ordinary practice and research.

In psychiatry, individual-based registries have provided key information on risks and benefits associated with the use of psychotropic drugs but they have rarely been employed for monitoring and evaluating the everyday prescribing of psychopharmacological treatments. This article describes the cultural background that gave impetus to the idea of registering all prescriptions of psychotropic drugs dispensed by physicians working in the South Verona community mental health service, and presents the methodology employed to develop such a registry in a community psychiatric service where a psychiatric case register (PCR) has been operating since 1978. We developed a registry including every patient receiving psychotropic medications in ordinary practice. This registry is linked to the PCR in order to obtain data on social and demographic characteristics, clinical symptoms, diagnosis, use of services, and outcomes. No exclusion criteria are allowed--anyone receiving treatment is automatically included. This system, which can link drug and service-use data with hard outcome indicators, can generate information on the proportion of subjects discontinuing treatment, switching medication because of side-effects, recovery or inefficacy, as well as on the proportion of subjects failing to return to the physician, and the proportion of patients who improve. The innovative aspect of this approach is that this registry is developed, organized and used by physicians interested in monitoring their clinical practice and in providing patients, relatives and the public with accurate information on drug use in their specific context of care.

Drug Monitoring↗
PubMed2005

Impact of regulatory changes on first- and second-generation antipsychotic drug consumption and expenditure in Italy.

BACKGROUND: In 1994 a change in drug reimbursement status was implemented in Italy according to cost-effectiveness criteria. The aim of this study was to examine the impact of these changes on the use of antipsychotic (AP) drugs. METHODS: Data concerning actual quantities of antipsychotic agents dispensed in Italy from 1995 to June 2003 were obtained from the Italian Ministry of Health. For each antipsychotic agent, the number of defined daily doses (DDDs) per 1,000 inhabitants per day was calculated, as well as the annual expenditure in Euros. RESULTS: From 1995 to June 2003 prescriptions for first-generation antipsychotic agents (FGAs) progressively decreased from 2.54 to 2.0 DDD/1,000/day; in contrast, prescriptions for second-generation antipsychotic agents (SGAs) progressively rose up to 1.75 DDD/1,000/day in 2003. Overall, from 1995 to 2003 antipsychotic prescriptions rose from 2.54 to 3.75 DDD/1,000/day. In 2003 the antipsychotic drug most frequently used was haloperidol, followed by olanzapine and risperidone. In 2003 the use of SGAs accounted for nearly 50% of overall DDD/1,000/day of AP agents. The cost of these new drugs, however, accounted for more than 80% of the total AP expenditure. CONCLUSIONS: In Italy, the progressive increase in the utilisation of SGAs has been accompanied by a moderate decrease in the utilisation of phenothiazines and by an almost constant use of butyrophenones. The policy of reimbursing the use of SGAs only in subjects who could not tolerate FGAs eventually failed to significantly affect the pattern of antipsychotic consumption and expenditure; moreover, when this policy was eliminated at the beginning of 2001, the pattern of consumption and expenditure did not change.

Antipsychotic Agents↗
PubMed2005

Psychotropic drug epidemiology: the road travelled, the road ahead.

Psychotropic drug epidemiology is a discipline developed to study the use and the effects of drugs in large numbers of individuals. It describes how drugs are prescribed and utilized, investigates reasons underlying prescriptions, and monitors outcomes and variables which may affect these outcomes. In this article the main purposes, study designs and limitations of current pharmacoepidemiological approaches are reviewed with the aim of assessing whether this discipline can constitute a permanent link between the experimental world of clinical trials and the real world of everyday prescribing. We support the notion that evidence generated in clinical practice, by means of pharmacoepidemiological studies, should increasingly be used to develop and suggest innovative research hypotheses to be subsequently tested in pragmatic experimental studies.

Drug Prescriptions↗
PubMed2005

Imputing response rates from means and standard deviations in meta-analyses.

The principle of intention-to-treat analysis must be strictly applied to both individual randomized controlled trial and meta-analysis but, in doing so, would involve imputation of some missing data. There is little literature on how to perform this in the case of meta-analysis. For dichotomous outcome measures, one possible strategy is to carry out a sensitivity analysis based on the so-called best case/worst case analyses. For continuous outcomes, it may be possible to achieve this if we can dichotomise the continuous outcomes. Here, we empirically examined the appropriateness of converting continuous outcomes (expressed as mean+/-SD) into dichotomous outcomes (expressed as response rates) in four completed meta-analyses of depression and anxiety, assuming normal distribution of the continuous outcome measures. The agreement between the actually observed versus the imputed raw numbers of responders was indicated by an intraclass correlation coefficient of 0.97 (95% confidence interval 0.95-0.98). The pooled relative risks of the four meta-analyses based on the imputed values were virtually identical to those based on the actually observed values. When individual trials report the means+/-SDs of their outcome measures but fail to report response rates, it may therefore be possible to impute the response rates based on the means+/-SDs, and then submit the meta-analysis to worst case/best case analyses. This would allow a more robust and clinically interpretable estimation of the true, underlying treatment effect to be made.

Data Interpretation, Statistical↗
PubMed2005

Past use of selective serotonin reuptake inhibitors and the risk of cerebrovascular events in the elderly.

Treatment with selective serotonin reuptake inhibitors (SSRIs) has been associated with intracranial bleeding abnormalities. We investigated the relationship between past exposure to SSRIs and occurrence of cerebrovascular accidents in the elderly. From the regional database of hospital admissions of Lombardy, Italy, we extracted all patients aged 65 years or above with cerebrovascular-related outcomes for the year 2002. From the regional database of prescriptions reimbursed by the National Health Service, we extracted all patients aged 65 years or above who received antidepressant prescriptions during 2001. The two databases were linked anonymously using the individual patient code. The analysis showed that the proportion of cerebrovascular events in those exposed to SSRIs was 135/66 335 [0.20%, 95% confidence interval (CI) 0.17-0.24], whereas the proportion of cerebrovascular accidents in those exposed to tricyclic antidepressants (TCAs) was 28/18 620 (0.15%, 95% CI 0.09-0.21). After background group differences were controlled for, exposure to SSRIs did not increase the risk of accidents (adjusted odds ratio 1.31, 95% CI 0.87-1.97). Although the risk of cerebrovascular accidents is a rare but serious event that should carefully be monitored during antidepressant therapy, this study indicated an absence of difference between TCAs and SSRIs.

Aged↗
PubMed2005

Determinants of antipsychotic polypharmacy in psychiatric inpatients: a prospective study.

A recent survey of clinicians' opinions suggested that antipsychotic polypharmacy is reserved for particularly severe cases, and that it is intended to avoid high doses of a single drug. In the present study, we tested these clinicians' reasons for antipsychotic polypharmacy in a sample of Italian psychiatric inpatients. During a 6-year recruitment period, all psychiatric patients receiving antipsychotic therapy at discharge from an inpatient facility were included. Sociodemographic and clinical data were collected, and the 18-item version of the Brief Psychiatric Rating Scale was administered on admission and before discharge. At discharge, data on length of inpatient stay, psychotropic drug therapy and treatment adherence were collected. Prescribed daily doses were converted into multiples of the defined daily doses. A total of 354 inpatients receiving antipsychotic treatment at discharge were included. Of these, 100 (28%) were discharged with two or more antipsychotic drugs. After background group differences were controlled for, positive symptoms, manic/hostility symptoms and polypharmacy on admission were predictors of polypharmacy at discharge. The risk of high-dose antipsychotics in patients receiving polypharmacy at discharge was 10-fold higher than that in patients receiving one antipsychotic (odds ratio 10.70, 95% confidence interval 4.78-23.97, P<0.001). The perception of clinicians is to reserve antipsychotic polypharmacy for severe, persistent and difficult-to-treat cases, and this was confirmed by the finding that patients discharged on two or more antipsychotic agents were more severely ill on admission. Conversely, the theoretical advantage of avoiding a high dose of a single drug is counterbalanced by the documented disadvantage of administering high total doses.

Adolescent↗
PubMed2005

Second-generation antipsychotics and risk of cerebrovascular accidents in the elderly.

Concern has been recently raised for risperidone and olanzapine, possibly associated with cerebrovascular events in placebo-controlled trials conducted in elderly subjects with dementia. We investigated the relationship between exposure to second-generation antipsychotics (SGAs) and occurrence of cerebrovascular accidents in the elderly. From the regional database of hospital admissions of Lombardy, Italy, we extracted all patients aged 65 or older with cerebrovascular-related outcomes for the year 2002. From the regional database of prescriptions reimbursed by the National Health Service, we extracted all patients aged 65 or older who received antipsychotic prescriptions during 2001. The 2 databases were linked anonymously using the individual patient code. The proportions of cerebrovascular accidents were 3.31% (95% confidence interval, 2.95-3.69) in elderly subjects exclusively exposed to SGAs and 2.37% (95% confidence interval, 2.19-2.57) in elderly subjects exclusively exposed to first-generation antipsychotics. After background group differences were controlled for, exposure to SGAs significantly increased the risk of accidents. The analysis of cerebrovascular events in elderly subjects exposed to each individual SGA, in comparison with exposure to haloperidol, showed a significantly increased risk for risperidone only (adjusted odds ratio, 1.43; 95% confidence interval, 1.12-1.93). These data provide preliminary epidemiological evidence that exposure to SGAs, in comparison with exposure to first-generation antipsychotics, significantly increased the risk of cerebrovascular accidents in the elderly.

Aged↗
PubMed2005

Sex differences in the subjective tolerability of antipsychotic drugs.

In recent years, research efforts have been directed to better characterize the subjective experience of taking psychotropic drugs. This study investigated the sex difference in the subjective tolerability of antipsychotic drugs. Participants were recruited from patients under the care of psychiatric services serving geographical catchment areas in Croydon (UK), Verona (Italy), Amsterdam (Netherlands), and Leipzig (Germany). Clinically unstable patients with a clinical diagnosis of schizophrenia and a research diagnosis of schizophrenia, established using the Item Group Checklist of the Schedule for Clinical Assessment in Neuropsychiatry, were enrolled. Antipsychotic subjective tolerability was rated by means of the Liverpool University Neuroleptic Side Effect Rating Scale. During the recruitment period, 245 men and 164 women with schizophrenia were recruited. In both sexes, the most frequently reported side effects were difficulty in concentrating, tiredness, and weight gain; these side effects occurred in approximately 50% of men and in up to 70% of women. Extrapyramidal and anticholinergic reactions were reported more often by women, whereas men reported sexual problems more often. After background group differences were controlled for, sex was the strongest determinant of the subjective tolerability of antipsychotic drugs. We therefore conclude that sex differences in the subjective tolerability of antipsychotic drugs should be taken into account in the pharmacological management of patients with schizophrenia. Studies should no longer consider men and women as a homogeneous group, given that the subjective tolerability of antipsychotic drugs substantially differs between sexes.

Adolescent↗