“I quesiti e le necessità non soddisfatte
In tema di bambini allergici: pediatri di
famiglia e ospedaliero a confronto”
Dott. Alberto Ferrando
Ass. Pediatri Extraospedalieri Liguri
L’EBM consente al medico di valutare
le incertezze della medicina che devono
essere analizzate quantitativamente per
razionalizzare e sistematizzare le informazioni
scaturite dall'osservazione clinica;
gli fornisce strumenti idonei per valutare
la performance di test diagnostici spesso
non adeguatamente testati e l'efficacia
dei farmaci spesso dubbia o addirittura
non documentata.
Le fonti tradizionali di aggiornamento:
•Il
collega esperto
•I trattati
•Le Riviste
•Le Revisioni tradizionali
Collega esperto: Nessun collega per quanto esperto può
garantire attualità, obiettività e completezza delle
informazioni fornite, perche’ i dati derivati
dall'esperienza non possono essere generalizzati; infatti il
loro confronto con standard evidence-based, suggerisce
che questo strumento non e’ adeguato per trasferire i
risultati della ricerca alla pratica clinica.
Inoltre, e’ fondamentale distinguere il collega autoritario,
che può fornire solo il contributo dell'opinione personale,
dalla vera autorità clinica che, consapevole dei limiti
dell'esperienza individuale e del valore della ricerca
clinica, motiva qualunque risposta con precisi riferimenti
alla letteratura originale.
Le riviste :
I medici dichiarano di dedicare alla lettura delle riviste
1-3 ore alla settimana, ma spesso ricorrono ai periodici
distribuiti gratuitamente: queste pubblicazioni, definite
con una colorita espressione "riviste pattumiera " ,
risentono spesso di interessi promozionali, raramente
comprendono lavori originali, non prevedono revisioni
critiche e gli indici analitici sono insufficienti
o addirittura non esistono.
Le riviste :
I medici dichiarano di dedicare alla lettura delle riviste
1-3 ore alla settimana, ma spesso ricorrono ai periodici
distribuiti gratuitamente: queste pubblicazioni, definite
con una colorita espressione "riviste pattumiera " ,
risentono spesso di interessi promozionali, raramente
comprendono lavori originali, non prevedono revisioni
critiche e gli indici analitici sono insufficienti
o addirittura non esistono.
Volume dell'informazione:
oltre due milioni di articoli sono
pubblicati annualmente in più di
20.000 riviste, con un ritmo di
espansione annuo del 6-7%.
Volume dell'informazione:
oltre due milioni di articoli sono
pubblicati annualmente in più di
20.000 riviste, con un ritmo di
espansione annuo del 6-7%.
Disseminazione dell'informazione:
gli articoli che riguardano un
determinato problema, sono
pubblicati in riviste ed in annate
diverse
Difficoltà a reperire le informazioni
clinicamente utili: infatti molti studi
non riguardano la medicina clinica,
ma sono messaggi tra ricercatori
Qualità dell'informazione:
la regola del "publish or perish", fa sì
che una corretta metodologia e’ limitata
solo a pochi studi, per cui buona parte
della produzione scientifica, anche
su riviste autorevoli, risulta poco
affidabile per decisioni cliniche
La formazione universitaria non
fornisce competenze specifiche per
la ricerca e l'approccio critico alla
letteratura biomedica
Pertanto, anche se esistono valide
strategie per utilizzare la letteratura
nella risoluzione di problemi clinici
e l'esplosione del fenomeno Internet
offre l'infrastruttura fisica ideale ,
e’ impresa ardua e spesso scoraggiante
per il singolo medico ricavare indicazioni
di comportamento pratico dalla
letteratura biomedica.
Cochrane Database Syst Rev 2001;3:CD002165
Pneumococcal vaccine for asthma (Cochrane Review).
Sheikh A, Alves B, Dhami S
Deparment of General Practice and Primary Health Care, Imperial College School of Medicine, Reynolds Building, Charing Cross Campus, St Dunstan's Road,
London, UK, W6 8RP. [email protected]
CONCLUSIONS: This review found very limited evidence to support
the routine use of pneumococcal vaccine in people with asthma. A
randomised trial of vaccine efficacy in children and adults with asthma is
needed.
From The Cochrane Library, Issue 1, 2002.
Addition of anti-leukotriene agents to inhaled corticosteroids
for chronic asthma (Cochrane Review)
Ducharme F, Hicks G, Kakuma R
A substantive amendment to this systematic review was last made on 25 October 2001. Cochrane reviews are regularly checked and updated if
necessary.
Search strategy: We searched Medline, Embase, Cinahl (until September 2001), reference lists of review articles and trials, contacted
international headquarters of AL manufacturers and ATS meeting abstracts (1998-2000).
Selection criteria: Randomised placebo-controlled trials of asthmatics aged 2 years and older with at least one month intervention.
Data collection and analysis: Two reviewers assessed quality and extracted data independently. Trials were grouped by asthma control at
baseline (symptomatic or well-controlled) and dose of ICS in the control group (same or double).
Main results: Of 438 citations, 13 (12 adult and 1 paediatric) trials met inclusion criteria. Seven were published in full-text.
Reviewers' conclusions: There is insufficient evidence to firmly support the use of licensed doses of
anti-leukotrienes as add-on therapy to inhaled glucocorticoids. Addition of anti-leukotrienes to inhaled
glucocorticoids may slightly improve asthma control, but the available data do not permit this strategy to be
recommended as a substitute for increasing the dose of inhaled glucocorticoids. Addition of anti-leukotrienes
may be associated with superior asthma control after glucocorticoid tapering, but a glucocorticoid-sparing
effect cannot be quantified at present.
From The Cochrane Library, Issue 1, 2002. Prepared and published by Update Software Ltd. All rights reserved.
Anti-leukotriene agents compared to inhaled corticosteroids in
the management of recurrent and/or chronic asthma (Cochrane
Review)
Ducharme FM, Hicks GC.
Selection criteria: Randomised controlled trials were included if they compared leukotriene antagonists with inhaled corticosteroids during a
minimal 30-day intervention period in asthmatic patients aged 2 years and older, and if measures of effectiveness other than compliance were
included.
Main results: Of 137 identified studies, ten met the inclusion criteria. Two are currently published in full-text. Most focused on subjects with
mild-to-moderate chronic asthma; two included children. Trial duration was 6 to 12 weeks with a few un-blinded trials lasting several months.
Daily dose of inhaled corticosteroids varied from 250 to 400 mcg of beclomethasone-equivalent; various anti-leukotriene preparation were tested.
There was no difference in the rate of patients with exacerbations that required systemic steroids [4 trials, Relative Risk (RR)=1.3, (95%
Confidence Interval (CI): 0.9, 1.9)]. Few trials contributed data to other outcomes. Improvement in lung function (FEV1 [N=3 trials, Standardised
Mean Difference (SMD)=0.3 (95% CI: 0.2, 0.4)]: morning PEFR [3 trials, SMD=0.4, (95% CI: 0.2, 0.5)]) and in quality of life [N=3 trials,
WMD=0.3, (95% CI: 0.1, 0.4)] favoured inhaled corticosteroids. A difference in favour of inhaled corticosteroids was observed for symptoms
[N=3 trials, SMD=0.3, (95% CI: = 0.2, 0.4)], night awakenings [N=2 trials, WMD= 0.6, (95% CI: 0.3, 0.9)], and rescue beta2-agonists [N=3
trials, SMD= 0.3, (95% CI: 0.2, 0.4)] Side effects were not different between groups, but anti-leukotriene therapy was associated with increase
risk of "withdrawals for any cause" [N=3 trials, RR=1.4, (95% CI: 1.1, 1.9)] and "withdrawals due to adverse effects" [N=3 trials, RR=1.9, (95%
CI: 1.1, 3.3)]
Reviewers' conclusions: Anti-leukotriene agents had a similar rate of exacerbations compared to inhaled
corticosteroids, but inhaled steroids produced better lung function and quality of life as well as
reduced symptoms, night awakenings and need for rescue beta2-agonist. Reliable conclusions cannot
yet be drawn regarding the efficacy of this treatment due to the paucity of trials published in full text.
From The Cochrane Library, Issue 1, 2002..
Gastro-oesophageal reflux treatment for asthma in adults and
children (Cochrane Review)
Gibson PG, Henry RL, Coughlan JL
A substantive amendment to this systematic review was last made on 11 August 1999. Cochrane reviews are regularly checked and updated if
necessary.
Background: Asthma and gastro-oesophageal reflux are both common medical conditions and often co-exist. Studies have shown conflicting
results concerning the effects of lower oesophageal acidification as a trigger of asthma. Furthermore, asthma might precipitate gastro-oesophageal
reflux . Thus a temporal association between the two does not establish that gastro-oesophageal reflux triggers asthma. Randomised trials of a
number of treatments for gastro-oesophageal reflux in asthma have been conducted, with conflicting results.
Objectives: The objective of this review was to evaluate the effectiveness of treatments for gastro-oesophageal reflux in terms of their benefit on
asthma.
Search strategy: The Cochrane Airways Group trials register, review articles and reference lists of articles were searched.
Selection criteria: Randomised controlled trials of treatment for oesophageal reflux in adults and children with a diagnosis of both asthma and
gastro-oesophageal reflux.
Data collection and analysis: Trial quality and data extraction were carried out by two independent reviewers. Authors were contacted for
confirmation or more data.
Main results: Nine trials met the inclusion criteria. Interventions included proton pump inhibitors (n=3), histamine antagonists (n=5), surgery
(n=1) and conservative management (n=1). Treatment duration ranged from 1 week to 6 months. A temporal association between asthma and
gastro-oesophageal reflux was investigated in 4 trials and found to be present in a proportion of participants in these trials. Anti-reflux treatment
did not consistently improve lung function, asthma symptoms, nocturnal asthma or the use of asthma medications.
Reviewers' conclusions: In asthmatic subjects with gastro-oesophageal reflux, (but who were not recruited
specifically on the basis of reflux-associated respiratory symptoms), there was no overall improvement in
asthma following treatment for gastro-oesophageal reflux. Subgroups of patients may gain benefit, but it
appears difficult to predict responders.
Vaccines for preventing influenza in people with asthma
(Cochrane Review)
Cates CJ, Jefferson TO, Bara AI, Rowe BH
A substantive amendment to this systematic review was last made on 21 August 2000. Cochrane reviews are regularly checked and updated if
necessary.
Background: Influenza vaccination is recommended for asthmatic patients in many countries as observational studies have shown that influenza
infection can be associated with asthma exacerbations, but influenza vaccination itself has the potential to adversely affect pulmonary function. A
recent overview concluded that there was no clear benefit of influenza vaccination in patients with asthma but this conclusions was not based on a
systematic search of the literature.
Objectives: Whilst influenza may cause asthma exacerbations, there is controversy about the use of influenza vaccinations, since they may
precipitate an asthma attack in some people. The objective of this review was to assess the effects of influenza vaccination in children and adults
with asthma.
Search strategy: We searched the Cochrane Airways Group trials register and checked reference lists of articles.
Selection criteria: Randomised trials of influenza vaccination in children (over two years of age) and adults with asthma. Studies involving
people with chronic obstructive pulmonary disease were excluded.
Data collection and analysis: Inclusion criteria and assessment of trial quality were applied by two reviewers independently. Data extraction was
done by two reviewers independently. Study authors were contacted for missing information.
Main results: Nine trials were included. Four of these trials were of high quality. One further article has been included since the previous version
of this review. Inclusion of the new trial has not altered the conclusions of this review. The included studies covered a wide diversity of people,
settings and types of influenza vaccination, so data from the different trials were not pooled. In one trial, no protective effect of influenza
vaccination against asthma exacerbation was demonstrated , but the incidence of influenza was low during the study period. A higher number of
asthma exacerbations following killed influenza vaccination was found in one trial (risk difference 3 1%, 95% confidence interval 0.3% to 5.8%).
When people with upper respiratory tract infections were excluded, this difference was no longer significant. A small trial using recombinant
vaccine found no significant difference in asthma exacerbations between the vaccinated and placebo groups.
Reviewers' conclusions: There is not enough evidence to assess the benefits and
risks of influenza vaccination for people with asthma.
House dust mite control measures for asthma (Cochrane Review)
Currently available evidence from controlled trials of chemical and
physical approaches to reducing exposure to house dust mite antigens
in the homes of mite-sensitive asthmatics does not provide a secure
basis for advice and policy. Further trials - one of them very large - are
currently in progress. The additional evidence from these studies will
help to clarify whether or not the substantial efforts required to
implement strategies intended to reduce mites can be expected to yield
beneficial effects of a magnitude that people with mite sensitive asthma
consider worthwhile
Early emergency department treatment of acute asthma with
systemic corticosteroids (Cochrane Review)
Rowe BH, Spooner C, Ducharme FM, Bretzlaff JA, Bota GW.
A substantive amendment to this systematic review was last made on 02 November 2000. Cochrane reviews are regularly checked and updated if
necessary.
Background: The airway edema and secretions associated with acute asthma are most effectively treated with anti-inflammatories such as
corticosteroids delivered by inhaled, oral, intravenous or intra-muscular routes. There is an unresolved debate about the use of systemic
corticorticoids in the early treatment of acute asthma for emergency department patients.
Objectives: To determine the benefit of treating patients with acute asthma with systemic corticosteroids within an hour of presenting to the
emergency department (ED).
Search strategy: Randomised controlled trials were identified from the Cochrane Airways Group Asthma Register. Primary authors and content
experts were contacted to identify eligible studies. Bibliographies from included studies and known reviews were searched.
Selection criteria: Only randomised controlled trials (RCTs) or quasi-randomised trials were eligible for inclusion. Studies were included if
patients presenting to the ED with acute asthma were treated with IV/IM or oral corticosteroids (CS) vs. placebo within 1 hour of arrival and
either admission rate or pulmonary function results were reported.
Data collection and analysis: Trial selection, data extraction and quality assessment were carried out independently by two reviewers, and
confirmed with corresponding authors.
Main results: Twelve studies involving 863 patients (435 corticosteroids; 428 placebo) were included. Early use of CS for acute asthma in the ED
significantly reduced admission rates (N = 11; pooled OR: 0.40, 95% CI: 0.21 to 0.78). This would correspond with a number needed to treat of 8
(95% CI: 5 to 21). This benefit was more pronounced for those not receiving systemic CS prior to ED presentation (N = 7; OR: 0.37, 95% CI:
0.19 to 0.70) and those with more severe asthma (N = 7; OR: 0.35, 95% CI: 0.21 to 0.59). Oral CS therapy in children was particularly effective
(N = 3; OR: 0.24, 95% CI: 0.11 to 0.53); no trials in adults used the oral route. Side effects were not significantly different between corticosteroid
treatments and placebo.
A further search was conducted in September 2000 which did not yield any further trials.
Reviewers' conclusions: Use of corticosteroids within 1 hour of presentation to an ED significantly reduces the need for hospital admission in
patients with acute asthma. Benefits appear greatest in patients with more severe asthma, and those not currently receiving steroids.
Children appear to respond well to oral steroids.
Family therapy for asthma in children (Cochrane Review)
Panton J, Barley EA
A substantive amendment to this systematic review was last made on 20 September 1999. Cochrane reviews are regularly checked and updated if
necessary.
Background: Psychosocial and emotional factors are important in childhood asthma. Nevertheless, drug therapy alone continues to be the main
treatment. Treatment programmes that include behavioural or psychological interventions have been developed to improve disturbed family
relations in the families of children with severe asthma. These approaches have been extended to examine the efficacy of family therapy to treat
childhood asthma in a wider group of patients. This review systematically examines these studies.
Objectives: Recognition that asthma can be associated with emotional disturbances has led to the investigation of the role of family therapy in
reducing the symptoms and impact of asthma in children. The objective of this review was to assess the effects of family therapy as an adjunct to
medication for the treatment of asthma in children.
Search strategy: We searched the Cochrane Airways Group trials register, Psychlit and Psychinfo.
Selection criteria: Randomised trials comparing children undergoing systematic therapy focusing on the family in conjunction with asthma
medication, with children taking asthma medication only.
Data collection and analysis: One reviewer applied the study inclusion criteria.
Main results: Two trials with a total of 55 children were included. It was not possible to combine
the findings of these two studies because of differences in outcome measures used. In one study,
gas volume, peak expiratory flow rate and daytime wheeze showed improvement in family
therapy patients compared to controls. In the other study, there was an improvement in overall
clinical assessment and number of functionally impaired days in the patients receiving family
therapy. There was no difference in forced expiratory volume or medication use in both studies.
Clin Exp Allergy 1999 May;29(5):611-7
Does early exposure to cat or dog protect against later allergy development?
Hesselmar B, Aberg N, Aberg B, Eriksson B, Bjorksten B
Department of Paediatrics, University of Goteborg, Goteborg.
[Medline record in process]
BACKGROUND: It is unknown which factors in modern western society that have caused the current
increase in prevalence of allergic diseases. Improved hygiene, smaller families, altered exposure to allergens
have been suggested... RESULTS: Children exposed to pets during the first year of life had a lower frequency
of allergic rhinitis at 7-9 years of age and of asthma at 12-13 years. Children exposed to cat during the first
year of life were less often SPT positive to cat at 12-13 years. The results were similar when those children
were excluded, whose parents had actively decided against pet keeping during infancy because of allergy in
the family. There was a negative correlation between the number of siblings and development of asthma and
allergic rhinitis. CONCLUSION: Pet exposure during the first year of life and increasing
number of siblings were both associated with a lower prevalence of allergic rhinitis and
asthma in school children.
PMID: 10231320, UI: 99248026