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The Cochrane Database of Systematic... Mar 2018Fluvastatin is thought to be the least potent statin on the market, however, the dose-related magnitude of effect of fluvastatin on blood lipids is not known. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Fluvastatin is thought to be the least potent statin on the market, however, the dose-related magnitude of effect of fluvastatin on blood lipids is not known.
OBJECTIVES
Primary objectiveTo quantify the effects of various doses of fluvastatin on blood total cholesterol, low-density lipoprotein (LDL cholesterol), high-density lipoprotein (HDL cholesterol), and triglycerides in participants with and without evidence of cardiovascular disease.Secondary objectivesTo quantify the variability of the effect of various doses of fluvastatin.To quantify withdrawals due to adverse effects (WDAEs) in randomised placebo-controlled trials.
SEARCH METHODS
The Cochrane Hypertension Information Specialist searched the following databases for randomised controlled trials up to February 2017: the Cochrane Central Register of Controlled Trials (CENTRAL) (2017, Issue 1), MEDLINE (1946 to February Week 2 2017), MEDLINE In-Process, MEDLINE Epub Ahead of Print, Embase (1974 to February Week 2 2017), the World Health Organization International Clinical Trials Registry Platform, CDSR, DARE, Epistemonikos and ClinicalTrials.gov. We also contacted authors of relevant papers regarding further published and unpublished work. No language restrictions were applied.
SELECTION CRITERIA
Randomised placebo-controlled and uncontrolled before and after trials evaluating the dose response of different fixed doses of fluvastatin on blood lipids over a duration of three to 12 weeks in participants of any age with and without evidence of cardiovascular disease.
DATA COLLECTION AND ANALYSIS
Two review authors independently assessed eligibility criteria for studies to be included, and extracted data. We entered data from placebo-controlled and uncontrolled before and after trials into Review Manager 5 as continuous and generic inverse variance data, respectively. WDAEs information was collected from the placebo-controlled trials. We assessed all trials using the 'Risk of bias' tool under the categories of sequence generation, allocation concealment, blinding, incomplete outcome data, selective reporting, and other potential biases.
MAIN RESULTS
One-hundred and forty-five trials (36 placebo controlled and 109 before and after) evaluated the dose-related efficacy of fluvastatin in 18,846 participants. The participants were of any age with and without evidence of cardiovascular disease, and fluvastatin effects were studied within a treatment period of three to 12 weeks. Log dose-response data over doses of 2.5 mg to 80 mg revealed strong linear dose-related effects on blood total cholesterol and LDL cholesterol and a weak linear dose-related effect on blood triglycerides. There was no dose-related effect of fluvastatin on blood HDL cholesterol. Fluvastatin 10 mg/day to 80 mg/day reduced LDL cholesterol by 15% to 33%, total cholesterol by 11% to 25% and triglycerides by 3% to 17.5%. For every two-fold dose increase there was a 6.0% (95% CI 5.4 to 6.6) decrease in blood LDL cholesterol, a 4.2% (95% CI 3.7 to 4.8) decrease in blood total cholesterol and a 4.2% (95% CI 2.0 to 6.3) decrease in blood triglycerides. The quality of evidence for these effects was judged to be high. When compared to atorvastatin and rosuvastatin, fluvastatin was about 12-fold less potent than atorvastatin and 46-fold less potent than rosuvastatin at reducing LDL cholesterol. Very low quality of evidence showed no difference in WDAEs between fluvastatin and placebo in 16 of 36 of these short-term trials (risk ratio 1.52 (95% CI 0.94 to 2.45).
AUTHORS' CONCLUSIONS
Fluvastatin lowers blood total cholesterol, LDL cholesterol and triglyceride in a dose-dependent linear fashion. Based on the effect on LDL cholesterol, fluvastatin is 12-fold less potent than atorvastatin and 46-fold less potent than rosuvastatin. This review did not provide a good estimate of the incidence of harms associated with fluvastatin because of the short duration of the trials and the lack of reporting of adverse effects in 56% of the placebo-controlled trials.
Topics: Cholesterol; Cholesterol, LDL; Controlled Before-After Studies; Dose-Response Relationship, Drug; Fatty Acids, Monounsaturated; Fluvastatin; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Indoles; Randomized Controlled Trials as Topic; Triglycerides
PubMed: 29508377
DOI: 10.1002/14651858.CD012282.pub2 -
The Cochrane Database of Systematic... Nov 2015The common cold is an upper respiratory tract infection, most commonly caused by a rhinovirus. It affects people of all age groups and although in most cases it is self... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The common cold is an upper respiratory tract infection, most commonly caused by a rhinovirus. It affects people of all age groups and although in most cases it is self limiting, the common cold still causes significant morbidity. Antihistamines are commonly offered over the counter to relieve symptoms for patients affected by the common cold, however there is not much evidence of their efficacy.
OBJECTIVES
To assess the effects of antihistamines on the common cold.
SEARCH METHODS
We searched CENTRAL (2015, Issue 6), MEDLINE (1948 to July week 4, 2015), EMBASE (2010 to August 2015), CINAHL (1981 to August 2015), LILACS (1982 to August 2015) and Biosis Previews (1985 to August 2015).
SELECTION CRITERIA
We selected randomised controlled trials (RCTs) using antihistamines as monotherapy for the common cold. We excluded any studies with combination therapy or using antihistamines in patients with an allergic component in their illness.
DATA COLLECTION AND ANALYSIS
Two authors independently assessed trial quality and extracted data. We collected adverse effects information from the included trials.
MAIN RESULTS
We included 18 RCTs, which were reported in 17 publications (one publication reports on two trials) with 4342 participants (of which 212 were children) suffering from the common cold, both naturally occurring and experimentally induced. The interventions consisted of an antihistamine as monotherapy compared with placebo. In adults there was a short-term beneficial effect of antihistamines on severity of overall symptoms: on day one or two of treatment 45% had a beneficial effect with antihistamines versus 38% with placebo (odds ratio (OR) 0.74, 95% confidence interval (CI) 0.60 to 0.92). However, there was no difference between antihistamines and placebo in the mid term (three to four days) to long term (six to 10 days). When evaluating individual symptoms such as nasal congestion, rhinorrhoea and sneezing, there was some beneficial effect of the sedating antihistamines compared to placebo (e.g. rhinorrhoea on day three: mean difference (MD) -0.23, 95% CI -0.39 to -0.06 on a four- or five-point severity scale; sneezing on day three: MD -0.35, 95% CI -0.49 to -0.20 on a four-point severity scale), but this effect is clinically non-significant. Adverse events such as sedation were more commonly reported with sedating antihistamines although the differences were not statistically significant. Only two trials included children and the results were conflicting. The majority of the trials had a low risk of bias although some lacked sufficient trial quality information.
AUTHORS' CONCLUSIONS
Antihistamines have a limited short-term (days one and two of treatment) beneficial effect on severity of overall symptoms but not in the mid to long term. There is no clinically significant effect on nasal obstruction, rhinorrhoea or sneezing. Although side effects are more common with sedating antihistamines, the difference is not statistically significant. There is no evidence of effectiveness of antihistamines in children.
Topics: Adult; Child; Common Cold; Histamine Antagonists; Humans; Randomized Controlled Trials as Topic; Time Factors
PubMed: 26615034
DOI: 10.1002/14651858.CD009345.pub2 -
Complementary Therapies in Clinical... Nov 2023To understand the placebo response of acupuncture and its effect on migraine and optimize the design of future acupuncture clinical trials on migraine treatment. (Meta-Analysis)
Meta-Analysis Review
AIM
To understand the placebo response of acupuncture and its effect on migraine and optimize the design of future acupuncture clinical trials on migraine treatment.
METHODS
Randomized controlled trials with sham acupuncture as a control in migraine treatment were searched in four English databases from inception to September 1, 2022. The primary outcome was placebo response rate. Secondary outcomes were migraine symptoms, emotional condition, and quality of life. Factors associated with placebo response were also explored. Results were combined using risk difference (RD) or standardized mean difference (SMD) and 95% confidence interval (CI) with a random effects model.
RESULTS
The final analysis included 21 studies involving 1177 patients. The pooled response rate of sham acupuncture was 0.34 (RD, 95% CI 0.23-0.45, I 89.8%). The results (SMD [95% CI]) showed significant improvements in migraine symptoms (pain intensity -0.56 [-0.73 to -0.38], and episode conditions -0.55 [-0.75 to -0.35]); emotional condition (anxiety scale -0.49 [-0.90 to -0.08] and depression scale -0.21 [-0.40 to -0.03]); and quality of life on the Migraine-Specific Quality-of-Life Questionnaire (restrictive 0.78 [0.61-0.95]; preventive 0.52 [0.35-0.68]; and emotional 0.45 [0.28-0.62]) and on the Medical Outcomes Study Short-Form (physical 0.48 [0.34-0.62] and mental 0.21 [0.02-0.41]). Only acupuncture treatment frequency had a significant impact on the placebo response rate (RD 0.49 vs. 0.14; p = 0.00).
CONCLUSIONS
The effect sizes for placebo response of sham acupuncture varied across migraine treatment trials. Further studies should routinely consider adjusting for a more complete set of treatment factors.
Topics: Humans; Quality of Life; Acupuncture Therapy; Migraine Disorders; Outcome Assessment, Health Care; Placebo Effect; Randomized Controlled Trials as Topic
PubMed: 37793307
DOI: 10.1016/j.ctcp.2023.101800 -
Pain Jan 2024This preregistered (CRD42021223379) systematic review and meta-analysis aimed to characterize the placebo and nocebo responses in placebo-controlled randomized clinical... (Meta-Analysis)
Meta-Analysis
This preregistered (CRD42021223379) systematic review and meta-analysis aimed to characterize the placebo and nocebo responses in placebo-controlled randomized clinical trials (RCTs) on painful diabetic neuropathy (PDN), updating the previous literature by a decade. Four databases were searched for PDN trials published in the past 20 years, testing oral medications, adopting a parallel-group design. Magnitude of placebo or nocebo responses, Cochrane risk of bias, heterogeneity, and moderators were evaluated. Searches identified 21 studies (2425 placebo-treated patients). The overall mean pooled placebo response was -1.54 change in the pain intensity from baseline [95% confidence interval (CI): -1.52, -1.56, I 2 = 72], with a moderate effect size (Cohen d = 0.72). The pooled placebo 50% response rate was 25% [95% CI: 22, 29, I 2 = 50%]. The overall percentage of patients with adverse events (AEs) in the placebo arms was 53.3% [95% CI: 50.9, 55.7], with 5.1% [95% CI: 4.2, 6] of patients dropping out due to AEs. The year of study initiation was the only significant moderator of placebo response (regression coefficient = -0.06, [95% CI: -0.10, -0.02, P = 0.007]). More recent RCTs tended to be longer, bigger, and to include older patients (N = 21, rs = 0.455, P = 0.038, rs = 0.600, P = 0.004, rs = 0.472, P = 0.031, respectively). Our findings confirm the magnitude of placebo and nocebo responses, identify the year of study initiation as the only significant moderator of placebo response, draw attention to contextual factors such as confidence in PDN treatments, patients' previous negative experiences, intervention duration, and information provided to patients before enrollment.
Topics: Humans; Nocebo Effect; Diabetic Neuropathies; Placebo Effect; Pain Measurement; Diabetes Mellitus
PubMed: 37530658
DOI: 10.1097/j.pain.0000000000003000 -
Primary Care Diabetes Jun 2023This review aims to identify the magnitude of the placebo effect in people with type 2 diabetes mellitus. Literature research was conducted Medline, Embase and Virtual... (Meta-Analysis)
Meta-Analysis Review
This review aims to identify the magnitude of the placebo effect in people with type 2 diabetes mellitus. Literature research was conducted Medline, Embase and Virtual Health Library for studies published between the date of inception and June 2021. The eligibility criteria included randomized controlled trials, showing comparison to placebo, having participants with type 2 diabetes mellitus, and having glycated hemoglobin (HbA1c) as the primary outcome. Meta-analysis was conducted with the effect of changing HbA1c in relation to the baseline. Exploration of heterogeneity was performed.The meta-analysis showed an increase in the average of HbA1c compared to the baseline of 0.14% (95% CI: 0.07-0.21). There was a significant difference between follow-up times (p = 0.03) and between administration routes (p = 0.01), with an increase in HbA1c in the oral route [0.15% (95% CI: 0.07-0.23)]. The meta-regression of the year of publication showed a significant downward trend (p = 0.01) of the increase in HbA1c compared to the baseline.In this study, the expected placebo effect of Hba1c reduction was not found; instead, higher Hba1c levels were observed in the control groups, although this effect was reduced over the years. Registration: PROSPERO ID CRD42020172797.
Topics: Humans; Diabetes Mellitus, Type 2; Glycated Hemoglobin; Placebo Effect
PubMed: 37003927
DOI: 10.1016/j.pcd.2023.03.006 -
Cardiovascular Drugs and Therapy Oct 2022To determine the effect of major antihypertensive classes on erectile function (EF) in patients with or at high risk of cardiovascular disease. (Meta-Analysis)
Meta-Analysis
PURPOSE
To determine the effect of major antihypertensive classes on erectile function (EF) in patients with or at high risk of cardiovascular disease.
METHODS
We performed a systematic review and frequentist network meta-analysis of randomized controlled trials assessing the effect of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, β-blockers, calcium channel blockers, and thiazide diuretics on EF compared to each other and to placebo (PROSPERO: CRD42020189529). Similarly, we performed a network meta-analysis to explore the effect of different β-blockers on erectile function (nebivolol, other vasodilating and non-vasodilating β-blockers, placebo). Records were identified through search of PubMed, Cochrane Library, and Scopus databases and sources of grey literature until September 2020.
RESULTS
We included 25 studies (7784 patients) in the qualitative and 16 studies in the quantitative synthesis. The risk of bias was concerning or high in the majority of studies, and inconsistency was also high. No significant differences in EF were demonstrated in the pairwise comparisons between major antihypertensive classes. Similarly, when placebo was set as the reference treatment group, no treatment strategy yielded significant effects on EF. In the β-blockers analysis, nebivolol contributed a beneficial effect on EF only when compared to non-vasodilatory β-blockers (OR 2.92, 95%CI 1.3-6.5) and not when compared to placebo (OR 2.87, 95%CI 0.75-11.04) or to other vasodilatory β-blockers (OR 2.15, 95%CI 0.6-7.77).
CONCLUSION
All antihypertensive medication classes seem to exert neutral or insignificant effects on EF. Further high-quality studies are needed to better explore the effects of antihypertensive medication on EF.
Topics: Adrenergic beta-Antagonists; Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Antihypertensive Agents; Calcium Channel Blockers; Diuretics; Erectile Dysfunction; Humans; Hypertension; Male; Nebivolol; Network Meta-Analysis; Sodium Chloride Symporter Inhibitors
PubMed: 33945044
DOI: 10.1007/s10557-021-07197-9 -
Neurological Sciences : Official... Feb 2022Nocebo effect is prevalent among neurological diseases, resulting in low adherence and treatment outcome. We sought to examine the nocebo effect in randomized controlled... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Nocebo effect is prevalent among neurological diseases, resulting in low adherence and treatment outcome. We sought to examine the nocebo effect in randomized controlled trials (RCTs) in multiple system atrophy (MSA).
METHODS
We searched RCTs in MSA from Medline since September, 2021. RCTs for drug treatment conducted in adult MSA patients with more than 5 cases in each treatment arm were included. We assessed the number of dropout due to placebo intolerance. We also did a symptomatic/disease-modifying subgroup analysis based on two different treatment purposes. The STATA software was used for statistical analysis. Overall heterogeneity was assessed using the Cochran Q and I.
RESULTS
Data were extracted from 11 RCTs fulfilling our search criteria. Of 540 placebo-treated patients, 64.2% reported at least one adverse event (AE) and 7.5% reported dropout because of AEs. The chance of dropping out because of an AE and experiencing at least one AE did not differ between placebo and active drug treatment arms. Besides, the pooled nocebo dropout rate in the symptomatic subgroup was similar to that of the disease-modifying subgroup.
CONCLUSION
In MSA RCTs, nocebo dropout rate was not at a low level among neurological disorders. Nocebo effect was an important reason of dropout because of AE in placebo and active drug treatment arms. Different treatment purposes may not influence nocebo effect.
Topics: Humans; MEDLINE; Multiple System Atrophy; Nocebo Effect; Treatment Outcome
PubMed: 34973075
DOI: 10.1007/s10072-021-05758-2 -
The Cochrane Database of Systematic... Jun 2016Analgesic medication is the most frequently prescribed treatment for low back pain (LBP), of which paracetamol (acetaminophen) is recommended as the first choice... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Analgesic medication is the most frequently prescribed treatment for low back pain (LBP), of which paracetamol (acetaminophen) is recommended as the first choice medication. However, there is uncertainty about the efficacy of paracetamol for LBP.
OBJECTIVES
To investigate the efficacy and safety of paracetamol for non-specific LBP.
SEARCH METHODS
We conducted searches on the Cochrane Central Register of Controlled Trials (CENTRAL, which includes the Back and Neck Review Group trials register), MEDLINE, EMBASE, CINAHL, AMED, Web of Science, LILACS, and IPA from their inception to 7 August 2015. We also searched the reference lists of eligible papers and trial registry websites (WHO ICTRP and ClinicalTrials.gov).
SELECTION CRITERIA
We only considered randomised trials comparing the efficacy of paracetamol with placebo for non-specific LBP. The primary outcomes were pain and disability. We also investigated quality of life, function, adverse effects, global impression of recovery, sleep quality, patient adherence, and use of rescue medication as secondary outcomes.
DATA COLLECTION AND ANALYSIS
Two review authors independently performed the data extraction and assessed risk of bias in the included studies. We also evaluated the quality of evidence using the GRADE approach. We converted scales for pain intensity to a common 0 to 100 scale. We quantified treatment effects using mean difference for continuous outcomes and risk ratios for dichotomous outcomes. We used effect sizes and 95% confidence intervals as a measure of treatment effect for the primary outcomes. When the treatment effects were smaller than 9 points on a 0 to 100 scale, we considered the effect as small and not clinically important.
MAIN RESULTS
Our searches retrieved 4449 records, of which three trials were included in the review (n = 1825 participants), and two trials were included in the meta-analysis. For acute LBP, there is high-quality evidence for no difference between paracetamol (4 g per day) and placebo at 1 week (immediate term), 2 weeks, 4 weeks, and 12 weeks (short term) for the primary outcomes. There is high-quality evidence that paracetamol has no effect on quality of life, function, global impression of recovery, and sleep quality for all included time periods. There were also no significant differences between paracetamol and placebo for adverse events, patient adherence, or use of rescue medication. For chronic LBP, there is very low-quality evidence (based on a trial that has been retracted) for no effect of paracetamol (1 g single intravenous dose) on immediate pain reduction. Finally, no trials were identified evaluating patients with subacute LBP.
AUTHORS' CONCLUSIONS
We found that paracetamol does not produce better outcomes than placebo for people with acute LBP, and it is uncertain if it has any effect on chronic LBP.
Topics: Acetaminophen; Analgesics, Non-Narcotic; Humans; Low Back Pain; Middle Aged; Randomized Controlled Trials as Topic; Treatment Outcome
PubMed: 27271789
DOI: 10.1002/14651858.CD012230 -
Journal of Pain Research 2017The present review investigated whether there are systematic sex differences in the placebo and the nocebo effect. (Review)
Review
OBJECTIVES
The present review investigated whether there are systematic sex differences in the placebo and the nocebo effect.
METHODS
A literature search was conducted in multiple electronic databases. Studies were included if the study compared a group or condition where a placebo was administered to a natural history group or similar cohort.
RESULTS
Eighteen studies were identified - 12 on placebo effects and 6 on nocebo effects. Chi-square tests revealed that 1) males responded more strongly to placebo treatment, and females responded more strongly to nocebo treatment, and 2) males responded with larger placebo effects induced by verbal information, and females responded with larger nocebo effects induced by conditioning procedures.
CONCLUSION
This review indicates that there are sex differences in the placebo and nocebo effects, probably caused by sex differences in stress, anxiety, and the endogenous opioid system.
PubMed: 28831271
DOI: 10.2147/JPR.S134745 -
The Prostate May 2022It is a common practice to control efficacy of pharmacological treatment with a placebo group. However, placebo itself may affect subjective and even objective results.... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
It is a common practice to control efficacy of pharmacological treatment with a placebo group. However, placebo itself may affect subjective and even objective results. The purpose of this study was to evaluate the placebo effect on symptoms of CP/CPPS to improve future clinical trials.
METHODS
A search at three databases (Scopus, MEDLINE, and Web of Science) was conducted to identify double-blind placebo-controlled clinical trials on the treatment of CP/CPPS published until April 2021. The primary outcome - National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) score.
SECONDARY OUTCOMES
Qmax, PVR, IPSS, and prostate volume.
RESULTS
A total of 3502 studies were identified. Placebo arms of 42 articles (5512 patients, median 31 patients) were included in the systematic review. Systematic review identified positive changes in the primary endpoint, meta-analysis of 10 articles found that NIH-CPSI total score results were significantly influenced by placebo, mean difference -4.2 (95% confidence interval [CI]: -6.31, -2.09). Mean difference of NIH-CPSI pain domain was -2.31 (95% CI: -3.4, -1.21), urinary domain -1.12 (95% CI: -1.62, -0.62), quality of life domain -1.67 (95% CI: -2.38, -0.96); p < 0.001 for all. In case of the objective indicator - Qmax, there were three articles included in the meta-analysis. Qmax mean change from baseline was 0.68 (95% CI: -0.85, 2.22, p = 0.38). Systematic review showed no significant changes in pain, measured by VAS or other scores, IPSS and PVR.
CONCLUSIONS
Placebo significantly affected the subjective parameters (NIH-CPSI) and limitedly affected various other measurements of pain (visual analog scale, McGill pain questionnaire). There was no long-term effect on IPSS and objective measurements (Qmax, PVR). This study can be used in further clinical trials to develop general rules of CPPS treatment assessment.
Topics: Chronic Disease; Chronic Pain; Humans; Male; Pelvic Pain; Placebo Effect; Prostatitis; Quality of Life; Randomized Controlled Trials as Topic
PubMed: 35133667
DOI: 10.1002/pros.24311