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J Critchley

Publications and source records attributed to J Critchley.

12 recordsLinked to original sources
PubMed2006

The population mortality benefits of maximizing the number of eligible patients receiving appropriate cardiology treatments in Ireland.

BACKGROUND: Coronary heart disease (CHD) mortality rates have been decreasing in many industrialized countries since the 1980s. Up to half this decrease can be attributed to evidence-based medical and surgical cardiology interventions. However, recent studies suggest that modern cardiology treatment uptake levels remain disappointingly low in many patient categories. AIM: To determine the potential for further reductions in CHD mortality in Ireland from increasing the number of eligible patients receiving cardiology treatments. METHODS: A previously validated, cell-based IMPACT CHD mortality model was used to integrate large amounts of data describing CHD patient numbers, and the effectiveness and uptake levels of specific medical and surgical treatments. The CHD mortality reductions potentially achievable through the increased use of specific treatments were then calculated, stratified by age and gender and tested using sensitivity analyses. RESULTS: In 2000, medical and surgical coronary disease treatments together prevented or postponed approximately 1950 CHD deaths in the adult population aged 25-84. However, increasing treatment levels to reach 80% of eligible patients might have prevented or postponed a further 2280 CHD deaths in 2000 (minimum estimate 860, maximum estimate 4000). The biggest gain was from maximizing the treatment uptake of eligible heart failure patients, followed by those receiving statins and secondary prevention therapies. DISCUSSION: Many eligible patients are currently not receiving appropriate evidence-based treatments that would reduce CHD mortality and morbidity. Our results suggest that increasing cardiology treatment uptake in Ireland could at least double the current therapeutic reduction in CHD mortality.

Adult↗
PubMed2006

Sulfadoxine-pyrimethamine plus artesunate versus sulfadoxine-pyrimethamine plus amodiaquine for treating uncomplicated malaria.

BACKGROUND: Artemisinin-based combination treatments are strongly advocated, but supplies are limited. Sulfadoxine combined with amodiaquine is an alternative non-artemisinin combination. OBJECTIVES: To compare sulfadoxine-pyrimethamine plus amodiaquine (SP plus AQ) with sulfadoxine-pyrimethamine plus artesunate (SP plus AS) for treating uncomplicated Plasmodium falciparum malaria. SEARCH STRATEGY: We searched the Cochrane Infectious Diseases Group Specialized Register (October 2005), CENTRAL (The Cochrane Library 2005, Issue 4), MEDLINE (1966 to October 2005), EMBASE (1988 to October 2005), LILACS (October 2005), and reference lists. We also contacted researchers and organizations working in this field. SELECTION CRITERIA: Randomized controlled trials comparing SP plus AS with SP plus AQ for treating uncomplicated P. falciparum malaria. DATA COLLECTION AND ANALYSIS: Two authors independently applied the inclusion criteria, extracted data, and assessed methodological quality. The primary outcome measure was treatment failure (parasitological or clinical evidence of treatment failure between start of treatment and day 28). We calculated the relative risk (RR) with 95% confidence intervals (CI) for dichotomous data. MAIN RESULTS: Four trials (775 participants) met the inclusion criteria. All were from areas of high and seasonal malaria transmission in Africa. Fewer participants using SP plus AQ failed treatment by day 28 (RR 0.59, 95% CI 0.42 to 0.83; 652 participants, 3 trials). Even excluding new infections, SP plus AQ performed better (RR 0.62, 95% CI 0.40 to 0.96; 649 participants, 3 trials). There was no statistically significant difference between the two treatments for treatment failure at day 14 (RR 1.14, 95% CI 0.47 to 2.78; 775 participants, 4 trials). SP plus AS was more effective at reducing gametocyte carriage at day seven (RR 2.31, 95% CI 1.36 to 3.92; 220 participants, 1 trial). One trial reported that one person - in the SP plus AQ group - developed severe malaria. Adverse events were poorly reported, but did not seem to differ in type and number between the two treatment combinations. AUTHORS' CONCLUSIONS: SP plus AQ performed better at controlling treatment failure at day 28, but was not as good as SP plus AS at reducing gametocyte carriage at day seven. Careful consideration of local resistance patterns is required because resistance to sulfadoxine-pyrimethamine and amodiaquine are high in many areas. In order to delay development of resistance to artesunate, the combination with sulfadoxine-pyrimethamine should only be considered where both drugs are known to be effective. Data on adverse events are still lacking.

Amodiaquine↗
PubMed2005

Fluoroquinolones for treating typhoid and paratyphoid fever (enteric fever).

BACKGROUND: Fluoroquinolones are recommended as first-line therapy for typhoid and paratyphoid fever, but how they compare with other cheaper antibiotics and different fluoroquinolones is unclear. OBJECTIVES: To evaluate fluoroquinolone antibiotics for treating enteric fever in children and adults compared with other antibiotics, different fluoroquinolones, and different treatment durations of the same fluoroquinolone. SEARCH STRATEGY: We searched the Cochrane Infectious Diseases Group Specialized Register (August 2004), CENTRAL (The Cochrane Library Issue 3, 2004), MEDLINE (1966 to August 2004), EMBASE (1974 to August 2004), LILACS (1982 to August 2004), conference proceedings, reference lists, and contacted researchers. SELECTION CRITERIA: Randomized controlled trials of fluoroquinolones in people with blood or bone marrow culture-confirmed enteric fever. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed the methodological quality of trials and extracted data. We calculated the odds ratio (OR) for dichotomous data with 95% confidence intervals. We analysed norfloxacin separately. MAIN RESULTS: Thirty-three trials met the inclusion criteria; 22 had unclear allocation concealment, and 29 were not blinded. Three trials exclusively included children, and two studied outpatients. The main analysis examined clinical failure, microbiological failure, and relapse. Compared with chloramphenicol, fluoroquinolones were not statistically significantly different for clinical (544 participants) or microbiological failure (378 participants) in adults; they reduced clinically diagnosed relapse in adults (OR 0.14, 0.04 to 0.50; 467 participants, 6 trials), but this was not statistically significant in participants with blood culture-confirmed relapse (121 participants, 2 trials). Compared with co-trimoxazole, we detected no statistically significant difference (82 participants, 2 trials). Among adults, fluoroquinolones reduced clinical failure compared with ceftriaxone (OR 0.08, 0.01 to 0.45; 120 participants, 3 trials), but showed no difference for microbiological failure or relapse. We detected no statistically significant difference between fluoroquinolones and cefixime (80 participants, 1 trial) or azithromycin (152 participants, 2 trials). In trials of hospitalized children, fluoroquinolones were not statistically significantly different from ceftriaxone (60 participants, 1 trial, involving norfloxacin) or cefixime (82 participants, 1 trial). Norfloxacin had more clinical failures than other fluoroquinolones (417 participants, 5 trials). Trials comparing different durations of fluoroquinolone treatment showed no statistically significant differences (693 participants, 8 trials). AUTHORS' CONCLUSIONS: Many trials were small, and methodological quality varied widely. Although enteric fever most commonly affects children, trials in this group were particularly sparse. Insufficient data in all comparisons preclude any firm conclusions to be made regarding superiority of fluoroquinolones over first-line antibiotics in children and adults.

Adult↗
PubMed2004

Chlorproguanil-dapsone for treating uncomplicated malaria.

BACKGROUND: In Africa, malaria is often resistant to chloroquine and sulfadoxine-pyrimethamine. Chlorproguanil-dapsone is a potential alternative. OBJECTIVES: To compare chlorproguanil-dapsone with other antimalarial drugs for treating uncomplicated falciparum malaria. SEARCH STRATEGY: We searched the Cochrane Infectious Diseases Group Specialized Register (May 2004), CENTRAL (The Cochrane Library Issue 2, 2004), MEDLINE (1966 to May 2004), EMBASE (1988 to May 2004), LILACS (May 2004), Biosis Previews (1985 to May 2004), conference proceedings, and reference lists, and contacted researchers working in this field. SELECTION CRITERIA: Randomized and quasi-randomized controlled trials comparing chlorproguanil-dapsone to other antimalarial drugs. DATA COLLECTION AND ANALYSIS: Two reviewers independently applied the inclusion criteria, extracted data, and assessed methodological quality. We calculated the relative risk (RR) for dichotomous data and weighted mean difference for continuous data, and presented them with 95% confidence intervals (CI). MAIN RESULTS: Six trials (n = 3352) met the inclusion criteria. Chlorproguanil-dapsone (with 1.2 mg chlorproguanil) as a single dose had fewer treatment failures than chloroquine (1 trial), but more treatment failures and people with parasitaemia at day 28 than sulfadoxine-pyrimethamine (3 trials). Two trials compared the three-dose chlorproguanil-dapsone (with 2 mg chlorproguanil) regimen with sulfadoxine-pyrimethamine in new attendees. There were fewer treatment failures with chlorproguanil-dapsone by day 7 (RR 0.30, CI 0.19 to 0.49; n = 827, 1 trial) and day 14 (RR 0.36, CI 0.24 to 0.53; n = 1709, 1 trial). Neither trial reported total failures by day 28. A further trial was carried out in participants selected because they had previously failed sulfadoxine-pyrimethamine. Adverse event reporting was inconsistent between trials, but chlorproguanil-dapsone was associated with more adverse events leading to discontinuation of treatment compared with sulfadoxine-pyrimethamine (RR 4.54, CI 1.74 to 11.82; n = 829, 1 trial). It was also associated with more red blood cell disorders (RR 2.86, CI 1.33 to 6.13; n = 1850, 1 trial). REVIEWERS' CONCLUSIONS: There are insufficient data about the effects of the current standard chlorproguanil-dapsone regimen (three-dose, 2 mg chlorproguanil). Randomized controlled trials that follow up to day 28, record adverse events, and use an intention-to-treat analysis are required to inform any policy decisions.

Adult↗
PubMed2004

Smoking cessation for the secondary prevention of coronary heart disease.

BACKGROUND: Although the importance of smoking as a risk factor for coronary heart disease is beyond doubt, the speed and magnitude of risk reduction when a smoker with coronary heart disease quits are still subjects of debate. OBJECTIVES: To estimate the magnitude of risk reduction when a patient with CHD stops smoking. SEARCH STRATEGY: We searched the Cochrane Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Science Citation Index, CINAHL, PsychLit, Dissertation Abstracts, BIDS ISI Index to Scientific and Technical Proceedings, UK National Research Register from the start of each database. Sixty-one large international cohort studies of cardiovascular disease were identified, and contact made with authors to search for any unpublished results. The search was supplemented by cross-checking references and contact with various experts. Date of last search was April 2003. SELECTION CRITERIA: Any prospective cohort studies of patients with a diagnosis of CHD, which include all-cause mortality as an outcome measure. Smoking status must be measured on at least two occasions to ascertain which smokers have quit, and followed-up for at least two years. DATA COLLECTION AND ANALYSIS: Eligibility and trial quality were assessed independently by two reviewers. MAIN RESULTS: Twenty studies were included. There was a 36% reduction in crude relative risk (RR) of mortality for those who quit smoking compared with those who continued to smoke (RR 0.64, 95% confidence interval 0.58 to 0.71). There was also a reduction in non-fatal myocardial infarctions (crude RR 0.68, 95% confidence interval 0.57 to 0.82). Many studies did not adequately address quality issues, such as control of confounding, and misclassification of smoking status. However, there was little difference in the results for the six 'higher quality' studies, and little heterogeneity between these studies. This review was not able to assess how quickly the risk of mortality was reduced. REVIEWER'S CONCLUSIONS: Quitting smoking is associated with a substantial reduction in risk of all-cause mortality among patients with CHD. The pooled crude RR was 0.64 (95% CI 0.58 to 0.71). This 36% risk reduction appears substantial compared with other secondary preventive therapies such as cholesterol lowering which have received greater attention in recent years. The risk reduction associated with quitting smoking seems consistent regardless of differences between the studies in terms of index cardiac events, age, sex, country, and time period. However, relatively few studies have included large numbers of older people, women, or people of non-European descent, and most were carried out in Western countries.

Coronary Disease↗
PubMed2003

Smoking cessation for the secondary prevention of coronary heart disease.

BACKGROUND: Although the importance of smoking as a risk factor for coronary heart disease is beyond doubt, the speed and magnitude of risk reduction when a smoker with coronary heart disease quits are still subjects of debate. OBJECTIVES: To estimate the magnitude of risk reduction when a patient with CHD stops smoking. SEARCH STRATEGY: We searched the Cochrane Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Science Citation Index, CINAHL, PsychLit, Dissertation Abstracts, BIDS ISI Index to Scientific and Technical Proceedings, UK National Research Register from the start of each database. Sixty-one large international cohort studies of cardiovascular disease were identified, and contact made with authors to search for any unpublished results. The search was supplemented by cross-checking references and contact with various experts. Date of last search was April 2003. SELECTION CRITERIA: Any prospective cohort studies of patients with a diagnosis of CHD, which include all-cause mortality as an outcome measure. Smoking status must be measured on at least two occasions to ascertain which smokers have quit, and followed-up for at least two years. DATA COLLECTION AND ANALYSIS: Eligibility and trial quality were assessed independently by two reviewers. MAIN RESULTS: Twenty studies were included. There was a 36% reduction in crude relative risk (RR) of mortality for those who quit smoking compared with those who continued to smoke (RR 0.64, 95% confidence interval 0.58 to 0.71). There was also a reduction in non-fatal myocardial infarctions (crude RR 0.68, 95% confidence interval 0.57 to 0.82). Many studies did not adequately address quality issues, such as control of confounding, and misclassification of smoking status. However, there was little difference in the results for the six 'higher quality' studies, and little heterogeneity between these studies. This review was not able to assess how quickly the risk of mortality was reduced. REVIEWER'S CONCLUSIONS: Quitting smoking is associated with a substantial reduction in risk of all-cause mortality among patients with CHD. The pooled crude RR was 0.64 (95% CI 0.58 to 0.71). This 36% risk reduction appears substantial compared with other secondary preventive therapies such as cholesterol lowering which have received greater attention in recent years. The risk reduction associated with quitting smoking seems consistent regardless of differences between the studies in terms of index cardiac events, age, sex, country, and time period. However, relatively few studies have included large numbers of older people, women, or people of non-European descent, and most were carried out in Western countries.

Coronary Disease↗