Efficacy of electronic cigarettes for tobacco smoking cessation: An adapted systematic review

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
T O'Dowd
Keyword(s):  
Smoking Cessation ◽  
Cohort Studies ◽  
Randomised Controlled Trials ◽  
Electronic Cigarettes ◽  
Controlled Trials ◽  
Significant Heterogeneity ◽  
Smoking Reduction ◽  
Significant Difference ◽  
Randomised Controlled

Abstract Background Worldwide smoking remains the leading cause of preventable morbidity and mortality. Electronic cigarettes (ECs) are increasingly used by tobacco smokers as an aid to smoking cessation; however, their efficacy remains uncertain. Methods Electronic databases, clinical trial registries and grey literature sources were searched. The aim was to examine randomised controlled trials or prospective cohort studies, published since the 2016 Cochrane review on this topic, that assessed the efficacy of ECs in achieving smoking cessation among current smokers. Results Two RCTs and five cohort studies, including a total of 16,460 participants, were eligible for inclusion. One RCT found sustained 1-year abstinence of 18.0% in the EC group versus 9.9% in the nicotine replacement therapy group (RR: 1.83; 95% CI 1.30 to 2.58; P < 0.001). The second RCT did not find a statistically significant difference in abstinence rates between EC users and non-users (RR 0.71). Of the five included cohort studies, four reported statistically significant RRs. Two found a positive association (RRs of 1.45 and 1.84) between EC use and smoking cessation but two studies showed EC use was associated with reduced smoking cessation (RRs of 0.25 and 0.35). Due to significant heterogeneity between the studies the data were deemed unsuitable for pooling into a meta-analysis. All trials assessing smoking reduction reported higher rates of reduction among EC users. No serious adverse events were reported with EC use. Follow-up periods of included trials ranged from one to four years, with an average of 1.6 years. Conclusions There is limited, low-quality evidence that ECs are an effective intervention for smoking cessation and smoking reduction. The overall quality of evidence is low as it is based on a small number of studies with inconsistent and imprecise results. Due to the short follow-up periods of the included trials, the long-term safety of ECs is unclear from this review. Key messages Limited evidence that electronic cigarettes are an effective smoking cessation intervention. Further well-designed randomised controlled trials are required to investigate the efficacy of ECs for smoking cessation.

scholarly journals How reliable are randomised controlled trials for studying the relationship between diet and disease? A narrative review

2016 ◽  
Vol 116 (3) ◽  
pp. 381-389 ◽  
Author(s):  
Norman J. Temple
Keyword(s):  
Cohort Studies ◽  
Randomised Controlled Trials ◽  
Critical Evaluation ◽  
Epidemiological Studies ◽  
Dietary Factors ◽  
Controlled Trials ◽  
Large Numbers ◽  
History Of ◽  
Randomised Controlled

AbstractLarge numbers of randomised controlled trials (RCT) have been carried out in order to investigate diet–disease relationships. This article examines eight sets of studies and compares the findings with those from epidemiological studies (cohort studies in seven of the cases). The studies cover the role of dietary factors in blood pressure, body weight, cancer and heart disease. In some cases, the findings from the two types of study are consistent, whereas in other cases the findings appear to be in conflict. A critical evaluation of this evidence suggests factors that may account for conflicting findings. Very often RCT recruit subjects with a history of the disease under study (or at high risk of it) and have a follow-up of only a few weeks or months. Cohort studies, in contrast, typically recruit healthy subjects and have a follow-up of 5–15 years. Owing to these differences, findings from RCT are not necessarily more reliable than those from well-designed prospective cohort studies. We cannot assume that the results of RCT can be freely applied beyond the specific features of the studies.

scholarly journals Smoking cessation in individuals who use vaping as compared with traditional nicotine replacement therapies: a systematic review and meta-analysis

BMJ Open ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. e044222
Author(s):  
Catherine M Pound ◽  
Jennifer Zhe Zhang ◽  
Ama Tweneboa Kodua ◽  
Margaret Sampson
Keyword(s):  
Systematic Review ◽  
Smoking Cessation ◽  
Cigarette Smoking ◽  
Randomised Controlled Trials ◽  
Meta Analysis ◽  
Controlled Trials ◽  
Smoking Reduction ◽  
Registration Number ◽  
Randomised Controlled

ObjectivesDespite the aggressive marketing of electronic nicotine device systems (ENDS) as smoking cessation tools, the evidence of their effectiveness is mixed. We conducted a systematic review of randomised controlled trials to determine the effect of ENDS on cigarette smoking cessation, as compared with other types of nicotine replacement therapies (NRT).DesignSystematic review and meta-analysis using the Grading of Recommendations Assessment, Development and Evaluation approach.Data sourcesMEDLINE, Embase, the CENTRAL Trials Registry of the Cochrane Collaboration using the Ovid interface, ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform trials registries were searched through 17 June 2020.Eligibility criteria for studiesRandomised controlled trials in which any type of ENDS was compared with any type of NRT, in traditional cigarette users.Data extraction and synthesisThe primary outcome was smoking cessation, defined as abstinence from traditional cigarette smoking for any time period, as reported in each included study, regardless of whether abstinence is self-reported or biochemically validated. Secondary outcomes included smoking reduction, harms, withdrawal and acceptance of therapy. A random-effect model was used, and data were pooled in meta-analyses where appropriate.ResultsSix studies were retained from 270. Most outcomes were judged to be at high risk of bias. The overall quality of evidence was graded as ‘low’ or ‘very low’. Pooled results showed no difference in smoking cessation (rate ratio (RR) 1.42, 95% CI 0.97 to 2.09), proportion of participants reducing smoking consumption (RR 1.25, 95% CI 0.79 to 1.98), mean reduction in cigarettes smoked per day (mean difference 1.11, 95% CI −0.41 to 2.63), or harms (RR 0.96, 95% CI 0.76 to 1.20), between groups.ConclusionWe found no difference in smoking cessation, harms and smoking reduction between e-cigarette and NRT users. However, the quality of the evidence was low. Further research is needed before widespread recommendations are made with regard to the use of ENDS.PROSPERO registration numberSystematic review registration number: protocol registered with the International Prospective Register of Systematic Reviews (PROSPERO) on February 27th, 2020; CRD42020169416.

scholarly journals Intensive Smoking Cessation Interventions in Denmark - Based on data from the Danish Smoking Cessation Database

2018 ◽  
Vol 8 (S3) ◽  
pp. 1-43
Author(s):  
Mette Rasmussen
Keyword(s):  
Smoking Cessation ◽  
Cohort Studies ◽  
Randomised Controlled Trials ◽  
Meta Analysis ◽  
Real Life ◽  
Successful Outcome ◽  
Controlled Trials ◽  
Set Up ◽  
Randomised Controlled ◽  
Study Designs

Background Tobacco smoking is by far the most deadly and preventable lifestyle factor for public health, both globally and nationally. Nevertheless, it is estimated that worldwide, more than 1.1 billion adults are smokers. Today, 16% (0.8 million) of the adult population in Denmark are daily smokers, while 23% (1.1 million) consider themselves smokers, and one in four deaths are smoking related. The most effective method of reducing smoking prevalence is by employing a two-tier strategy to 1) prevent adolescents from initiating smoking and 2) offer effective help to smokers to quit. The aim of this thesis was to evaluate the effect of intensive smoking cessation interventions (ISCI) on successful quitting through different study designs, synthesised from cohort studies and a review of randomised controlled trials. The aim was fulfilled through 4 scientific studies, each with their own objective. Studies A systematic review with meta-analysis (I) was set up to compare ISCI and shorter interventions in randomised controlled trials (RCT). Initially, 9,569 unique papers were identified, and, after screening for relevant studies, 18 RCTs were included, investigating a total of 10,131 smokers. The studies were primarily conducted in Western Europa and the USA. The body of evidence for three of four outcomes were graded moderate, and the last outcome was graded low. A random effect meta-analysis revealed that smokers randomised to ISCI were significantly more likely to be successful quitters compared to shorter interventions for all four outcomes. The primary outcome (continuous abstinence in the short and long term) increased the chance of success 3-fold. A methodological study (II) of the Danish National Smoking Cessation Database (SCDB) was undertaken. The development of the SCDB and the most commonly registered smoking cessation interventions (SCI) were described, as were the data collection and validity. Two cohort studies based on the data from the SCDB were conducted to evaluate the effectiveness of SCI in real life. One study investigated the effectiveness of five different SCIs (III) and found that the intensive Gold Standard Programme’ (GSP - Standard SCI in Denmark) was the only intervention that was effective for both men and women. The other cohort study was set up to investigate the effectiveness of the GSP in a vulnerable subgroup of smokers diagnosed with severe mental disorder (SMD) (IV). The study showed that smokers with SMD were significantly less likely to become successful quitters compared to smokers without mental disorders. However, one in every four smokers with SMD managed to stay continuously smoke-free for at least 6 months compared to one in three in the comparison group. The data were analysed using a mixed-effect logistic regression model. In both cohort studies, compliance was identified as the strongest predictor of a successful outcome. Conclusion This thesis adds to the evidence on intensive smoking cessation interventions (ISCI) through different study designs. The results from both study designs favoured ISCI, although the GSP was significantly less effective in smokers with SMD compared to smokers without mental illness. To develop effective SCI in the future, it is important to evaluate the effects in an RCT and to follow-up the post-implementation effects in real life (e.g., through a national SCDB).

scholarly journals Potential impact on estimated treatment effects of information lost to follow-up in randomised controlled trials (LOST-IT): systematic review

BMJ ◽  
2012 ◽  
Vol 344 (may18 1) ◽  
pp. e2809-e2809 ◽  
Author(s):  
E. A. Akl ◽  
M. Briel ◽  
J. J. You ◽  
X. Sun ◽  
B. C. Johnston ◽  
...  
Keyword(s):  
Systematic Review ◽  
Randomised Controlled Trials ◽  
Treatment Effects ◽  
Controlled Trials ◽  
Potential Impact ◽  
Randomised Controlled ◽  
Lost To Follow Up

scholarly journals The impact of a run-in period on treatment effects in cardiovascular prevention randomised control trials: A protocol for a comprehensive review and meta-analysis

2020 ◽  
Vol 3 ◽  
pp. 82
Author(s):  
Robert Murphy ◽  
Emer McGrath ◽  
Aoife Nolan ◽  
Andrew Smyth ◽  
Michelle Canavan ◽  
...  
Keyword(s):  
Randomised Controlled Trials ◽  
Treatment Effects ◽  
Meta Analysis ◽  
Cardiovascular Prevention ◽  
Controlled Trials ◽  
Loss To Follow Up ◽  
Relative Risks ◽  
Prevention Trials ◽  
Randomised Controlled

Background: A run-in period is often employed in randomised controlled trials to increase adherence to the intervention and reduce participant loss to follow-up in the trial population. However, it is uncertain whether use of a run-in period affects the magnitude of treatment effect. Methods: We will conduct a sensitive search for systematic reviews of cardiovascular preventative trials and a complete meta-analysis of treatment effects comparing cardiovascular prevention trials using a run-in period (“run-in trials”) with matched cardiovascular prevention trials that did not use a run-in period (“non-run-in trials”). We describe a comprehensive matching process which will match run-in trials with non-run-in trials by patient populations, interventions, and outcomes. For each pair of run-in trial and matched non-run-in trial(s), we will estimate the ratio of relative risks and 95% confidence interval. We will evaluate differences in treatment effect between run-in and non-run-in trials and our and our priamry outcome will be the ratio of relative risks for matched run-in and non-run-in trials for their reported cardiovascular composite outcome. Our secondary outcomes are comparisons of mortality, loss to follow up, frequency of adverse events and methodological quality of trials. Conclusions: This study will answer a key question about what influence a run-in period has on the magnitude of treatment effects in randomised controlled trials for cardiovascular prevention therapies.

Effect of action observation therapy on motor function in children with cerebral palsy: a systematic review of randomized controlled trials with meta-analysis

2020 ◽  
pp. 026921552095434
Author(s):  
Naglaa Abdelhaleem ◽  
Samar Taher ◽  
Menna Mahmoud ◽  
Ahmad Hendawy ◽  
Maged Hamed ◽  
...  
Keyword(s):  
Cerebral Palsy ◽  
Methodological Quality ◽  
Randomised Controlled Trials ◽  
Action Observation ◽  
Meta Analysis ◽  
Post Treatment ◽  
Controlled Trials ◽  
Children With Cerebral Palsy ◽  
Randomised Controlled

Objective: To evaluate the evidence of using Action Observation Therapy in the rehabilitation of children with Cerebral Palsy. Study design: Systematic review with meta-analysis of Randomised Controlled Trials. Methods: For the purpose of identifying relevant studies, six databases were searched from inception until July 2020. The methodological quality was assessed by Physiotherapy Evidence Database scale. The outcomes were classified within the framework of the International Classification of Functioning. A pooled meta-analysis was performed on studies that demonstrated homogeneity. Results: Twelve randomised controlled trials with 307 participants were included with six of them were included in the meta-analysis. Non-significant difference between the groups was demonstrated by meta-analysis. Results of capacity assessed in post treatment and follow up evaluation were (0.06, –0.22 to 0.34, 95% (CI); P = 0.69 and (–0.35, –0.96 to 0.27, 95% (CI); P = 0.27); respectively. Actual performance in post-treatment and follow up were (0.10, –0.22 to 0.48, 95% (CI); P = 0.62) and (0.01, –0.40 to 0.41, 95% (CI); P = 0.97); respectively. Perceived performance evaluated using (ABILHAND-KIDS) were (0.30, –0.28 to 0.89, 95% (CI); P = 0.31) and (0.15, –0.43 to 0.73, 95% (CI); P = 0.61) for post treatment and follow up; respectively. Overall effect on activity domain was (0.08, –0.11 to 0.28, 95% (CI); P = 0.86) immediately and (0.04, –0.33 to 0.26, 95% (CI); P = 0.49) at follow-up; respectively. Conclusion: No evidence of benefit had been found to draw a firm conclusion regarding the effectiveness of action observation therapy in the rehabilitation of children with cerebral palsy due to limitations in methodological quality and variations between studies.

scholarly journals Pharmacological and behavioural interventions to promote smoking cessation in adults with schizophrenia and bipolar disorders: a systematic review and meta-analysis of randomised trials

BMJ Open ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. e027389 ◽  
Author(s):  
Robert Pearsall ◽  
Daniel J Smith ◽  
John R Geddes
Keyword(s):  
Systematic Review ◽  
Mental Illness ◽  
Smoking Cessation ◽  
Serious Mental Illness ◽  
Randomised Controlled Trials ◽  
Meta Analysis ◽  
Public Health Problem ◽  
Controlled Trials ◽  
Major Public Health Problem ◽  
Randomised Controlled

ObjectiveSmoking in people with serious mental illness is a major public health problem and contributes to significant levels of morbidity and mortality. The aim of the review was to systematically examine the efficacy of methods used to aid smoking cessation in people with serious mental illness.MethodA systematic review and meta-analysis of randomised controlled trials to compare the effectiveness and safety of pharmacological and behavioural programmes for smoking cessation in people with serious mental illness. Electronic databases were searched for trials to July 2018. We used the Cochrane Collaboration’s tool for assessing the risk of bias.ResultsTwenty-eight randomised controlled trials were identified. Varenicline increased the likelihood of smoking cessation at both 3 months (risk ratio (RR) 3.56, 95% CI 1.82 to 6.96, p=0.0002) and at 6 months (RR 3.69, 95% CI 1.08 to 12.60, p=0.04). Bupropion was effective at 3 months (RR 3.96, 95% CI 1.86 to 8.40, p=0.0003), especially at a dose of 300 mg/day, but there was no evidence of effect at 6 months (RR 2.22, 95% CI 0.52 to 9.47, p=0.28). In one small study, nicotine therapy proved effective at increasing smoking cessation up to a period of 3 months. Bupropion used in conjunction with nicotine replacement therapy showed more effect than single use. Behavioural and bespoke interventions showed little overall benefit. Side effects were found to be low.ConclusionThe new information of this review was the effectiveness of varenicline for smoking cessation at both 3 and 6 months and the lack of evidence to support the use of both bupropion and nicotine products for sustained abstinence longer than 3 months. Overall, the review found relatively few studies in this population.

scholarly journals Protective effects of dietary PUFA against chronic disease: evidence from epidemiological studies and intervention trials

2013 ◽  
Vol 73 (1) ◽  
pp. 73-79 ◽  
Author(s):  
Thomas A. B. Sanders
Keyword(s):  
Chronic Disease ◽  
Cohort Studies ◽  
Cardiac Death ◽  
Lower Risk ◽  
Randomised Controlled Trials ◽  
Cochrane Review ◽  
Total Mortality ◽  
Partial Replacement ◽  
Controlled Trials ◽  
Randomised Controlled

This review considers evidence for a protective effect of PUFA on chronic disease. Estimates of PUFA intakes in prospective cohort studies are usually based on FFQ or biomarkers of intake. Cohort studies suggest that both linoleic and linolenic acid intake are associated with a lower risk of CHD. The intake of fish, the major source of long-chainn-3 PUFA is associated with a lower risk of both stroke and CHD, particularly sudden cardiac death. No relationship with common sites of cancer (breast and colon) and PUFA has been found. However, some recent studies suggest an association of high intakes ofn-3 PUFA with risk of prostate cancer. An updated Cochrane review of dietary fat modification (replacing SFA with PUFA) randomised controlled trials to prevent CHD found a 14 % lower incidence and a non-significant 7 % lower mortality from CHD. The effects of an increased intake ofn-3 PUFA on CHD incidence mortality have been tested in patients with pre-existing CHD in randomised controlled trials. Meta-analysis of these trials showed no overall benefit on total mortality or CVD incidence but a trend for lower risk of cardiac death was 0·91 (95 % CI 0·85, 0·98). At present, there is little evidence from other trials demonstrating the clear benefits or harm from increased intakes of PUFA. In conclusion, present evidence intakes benefit from partial replacement of SFA with a balanced mixture ofn-6 andn-3 PUFA which may contribute to CVD prevention.

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