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Results for “Meta- analysis”

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At least 1,513 records · Page 84Linked to original sources

PubMed2006

Effect of periodontal treatment on serum C-reactive protein levels: a systematic review and meta-analysis.

BACKGROUND: Systemic inflammation is increasingly being recognized as a risk factor for adverse cardiovascular events. Evidence is accumulating that associates periodontal disease with a higher risk for atherosclerotic plaque formation. A positive association between circulating C-reactive protein (CRP) levels and periodontal disease may be responsible for these observations. We undertook a systematic review and conducted a meta-analysis of the available evidence to examine the effect of periodontal treatment on systemic CRP levels and to assess the quality of the available evidence. METHODS: We conducted a systematic search of the English-language literature on the effect of periodontal treatment on CRP levels, as assessed by high-sensitivity assays, at least 2 months after periodontal treatment. The search was conducted in MEDLINE between 1966 and July 2005 and the Cochrane Central Register of Controlled Trials. We performed a meta-analysis using the DerSimonian and Laird random-effects model. RESULTS: The literature search yielded 814 citations of which 10 met the inclusion criteria. The meta-analysis of the randomized controlled trials (RCTs) showed that the difference in serum CRP levels is not significantly different between the two arms. Similarly, results from the single-cohort studies showed that the difference on serum CRP levels was not significantly different before and after treatment. CONCLUSIONS: There is now a large body of evidence to indicate that systemic inflammation is present in patients with periodontal disease. Thus, information from RCTs and single-cohort studies does not support the hypothesis that periodontal treatment can reduce systemic CRP levels.

C-Reactive Protein↗

PubMed2005

Systematic review and meta-analysis of the diagnostic accuracy of ultrasonography for deep vein thrombosis.

BACKGROUND: Ultrasound (US) has largely replaced contrast venography as the definitive diagnostic test for deep vein thrombosis (DVT). We aimed to derive a definitive estimate of the diagnostic accuracy of US for clinically suspected DVT and identify study-level factors that might predict accuracy. METHODS: We undertook a systematic review, meta-analysis and meta-regression of diagnostic cohort studies that compared US to contrast venography in patients with suspected DVT. We searched Medline, EMBASE, CINAHL, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, Database of Reviews of Effectiveness, the ACP Journal Club, and citation lists (1966 to April 2004). Random effects meta-analysis was used to derive pooled estimates of sensitivity and specificity. Random effects meta-regression was used to identify study-level covariates that predicted diagnostic performance. RESULTS: We identified 100 cohorts comparing US to venography in patients with suspected DVT. Overall sensitivity for proximal DVT (95% confidence interval) was 94.2% (93.2 to 95.0), for distal DVT was 63.5% (59.8 to 67.0), and specificity was 93.8% (93.1 to 94.4). Duplex US had pooled sensitivity of 96.5% (95.1 to 97.6) for proximal DVT, 71.2% (64.6 to 77.2) for distal DVT and specificity of 94.0% (92.8 to 95.1). Triplex US had pooled sensitivity of 96.4% (94.4 to 97.1%) for proximal DVT, 75.2% (67.7 to 81.6) for distal DVT and specificity of 94.3% (92.5 to 95.8). Compression US alone had pooled sensitivity of 93.8 % (92.0 to 95.3%) for proximal DVT, 56.8% (49.0 to 66.4) for distal DVT and specificity of 97.8% (97.0 to 98.4). Sensitivity was higher in more recently published studies and in cohorts with higher prevalence of DVT and more proximal DVT, and was lower in cohorts that reported interpretation by a radiologist. Specificity was higher in cohorts that excluded patients with previous DVT. No studies were identified that compared repeat US to venography in all patients. Repeat US appears to have a positive yield of 1.3%, with 89% of these being confirmed by venography. CONCLUSION: Combined colour-doppler US techniques have optimal sensitivity, while compression US has optimal specificity for DVT. However, all estimates are subject to substantial unexplained heterogeneity. The role of repeat scanning is very uncertain and based upon limited data.

Journal Article↗

PubMed2000

Anemia during pregnancy and birth outcome: a meta-analysis.

To determine the relationship between maternal anemia [hemoglobin (Hgb) < 10-11 g/dL] and various birth outcomes, a meta-analysis was conducted based on published literature identified by MEDLINE and manual search from 1966 through 1999. Odds ratios (OR) from selected studies were pooled according to the gestational age at anemia diagnosis. The meta-analysis shows that maternal anemia during early pregnancy was associated with slightly increased preterm birth [pooled adjusted OR (aOR): 1.32, 95% confidence interval (CI): 1.01-1.74], and nonstatistically significant increased low birth weight [pooled aOR: 1.39 (0.70-2.74)], and was not associated with fetal growth restriction [pooled aOR: 1.01 (0.73-1.38)]. However, there was a nonstatistically significant inverse relationship between anemia during late pregnancy and preterm birth [pooled aOR: 0.92 (0.54-1.84)] and low birth weight [pooled aOR: 0.80 (0.64-1.00)]. Anemia was not statistically significantly associated with hypertensive disorders of pregnancy regardless of stage of pregnancy [pooled OR: 0.80 (0.53-1.20)]. The relationship between anemia and perinatal mortality was inconclusive. A few studies indicated that severe maternal anemia (Hgb < 8-8.5 g/dL) was associated with increased risk of poor outcomes. We conclude that early pregnancy anemia is associated with slightly increased risk of preterm birth. The trend toward an inverse association of anemia determined during late pregnancy with preterm birth and low birth weight may reflect the benefit of plasma volume expansion.

Adult↗

PubMed2004

Effect of dialysis modality on plasma fibrinogen concentration: a meta-analysis.

BACKGROUND: Concentrations of plasma fibrinogen, a vascular risk factor, tend to be greater in patients on peritoneal dialysis (PD) than hemodialysis (HD) therapy, like concentrations of serum cholesterol, lipoprotein(a), and transthyretin, despite the substantial loss of protein during PD. Worse vascular outcome has been noted in PD patients compared with HD patients in several studies. METHODS: In this study, the mean difference in plasma fibrinogen levels (PD-HD) was quantified by means of meta-analysis of mean differences found in 12 cohorts with both PD and HD patients (set 1; N = 630) by using a fixed-effects model and meta-analysis of mean fibrinogen values reported in 30 cohorts of patients on a single dialysis modality (set 2; 8 PD cohorts, 22 HD cohorts; N = 2,096) by using a mixed model. RESULTS: On meta-analysis, the weighted mean difference (PD-HD) was 105 mg/dL (95% confidence interval [CI], 86 to 124 [3.1 micromol/L; 95% CI, 2.5 to 3.6]) in set 1 and 103 mg/dL (95% CI, 53 to 153 [3.0 micromol/L; 95% CI, 1.6 to 4.5) in set 2. CONCLUSION: Like other vascular risk factors, such as cholesterol and lipoprotein(a), plasma fibrinogen level is markedly greater in PD than HD patients, with an approximate difference of 100 mg/dL [2.9 mumol/L]. Different plasma reference ranges for fibrinogen need to be defined for PD and HD patients. The mechanism for the difference and the possible role of hyperfibrinogenemia in worsening vascular disease in PD patients deserve study.

Cohort Studies↗

PubMed2002

Gender difference in HIV RNA levels: a meta-analysis of published studies.

Plasma HIV RNA copy number is a strong prognostic marker of progression to AIDS in antiretroviral-naive persons. Recent research suggests women have lower HIV RNA levels than comparable men. Because clinical care recommendations currently include HIV RNA thresholds as a guide to initiating antiretroviral therapy (ART), the authors undertook the present quantitative meta-analysis to explore the relation between gender and plasma HIV RNA levels. A gender difference in HIV RNA levels was observed in the CD4-unadjusted and -adjusted analyses. The summary estimate including only CD4-adjusted results with the lowest heterogeneity indicated that on average, women have 41% lower plasma HIV RNA levels than men (-.23 log; 95% confidence interval [CI], -.16 to -.31 log ). Because numerous studies have found similar HIV disease progression rates in men and women, adjusted for CD4 but not HIV RNA, the present meta-analysis supports the use of lower HIV RNA thresholds in women than in men to guide initiation of ART. Given the patient characteristics in the original studies used in this meta-analysis, the results are most likely to apply to therapy-naive persons with CD4 lymphocyte counts >200 cells/mm, a subgroup for whom HIV RNA levels may strongly influence the decision to initiate therapy.

Acquired Immunodeficiency Syndrome↗

PubMedDate not supplied

[Value and limits of conventional or cumulative meta analysis in obstetrics and gynecology].

The authors describe some situations where meta-analyses would have been of great benefit if they have been done or sufficiently published. They emphasize several problems ensued by this new method: if possible, meta-analyses have to be done each time a new trial is analysed, according to a precise method. Cumulative meta-analysis should rely on a regular and prospective registration of clinical trials. In all cases, meta-analyses should be available to a large number of physicians, in the main interest of patients.

Betamethasone↗

PubMed2005

Meta-analysis of postoperative adjuvant chemotherapy with tegafur-uracil in non-small-cell lung cancer.

PURPOSE: Recent clinical trials have shown the efficacy of platinum-based adjuvant chemotherapy for completely resected non-small-cell lung cancer (NSCLC). In Japan, many clinical trials of adjuvant chemotherapy with tegafur-uracil (UFT) have been conducted, and some trials showed positive results while others showed negative results. Thus, we performed a meta-analysis to assess the efficacy of postoperative adjuvant chemotherapy with UFT in NSCLC. METHODS: Among nine trials of postoperative adjuvant UFT-containing chemotherapy, six trials comparing surgery alone with surgery plus UFT were identified. Of six trials, two were three-arm trials including cisplatin-based chemotherapy followed by UFT, and data from that arm were not included in the meta-analysis. RESULTS: Of 2,003 eligible patients, most (98.8%) had squamous cell carcinoma or adenocarcinoma, and most had stage I disease; the tumor classification was T1 in 1,308 (65.3%), T2 in 674 (33.6%), and the nodal status was N0 in 1,923 (96.0%). The two treatment groups did not differ significantly in major prognostic factors. The median duration of follow-up was 6.44 years. The survival rates at 5 and 7 years were significantly higher in the surgery plus UFT group (81.5% and 76.5%, respectively) than in the surgery alone group (77.2% and 69.5%, respectively; P = .011 and .001, respectively). The overall pooled hazard ratio was 0.74, and its 95% CI was 0.61 to 0.88 (P = .001). CONCLUSION: This meta-analysis showed that postoperative adjuvant chemotherapy with UFT was associated with improved 5- and 7-year survival in a Japanese patient population composed primarily of stage I adenocarcinoma patients.

Adenocarcinoma↗

PubMed2007

Obesity and the risk of epithelial ovarian cancer: a systematic review and meta-analysis.

Obesity is a risk factor for several hormone-related cancers but evidence for an effect on risk of epithelial ovarian cancer remains inconclusive. Many studies evaluating this association have had insufficient statistical power to detect modest effects, particularly for histological subtypes of ovarian cancer. We have therefore assembled the published evidence on obesity and ovarian cancer in a systematic literature review and meta-analysis. We identified eligible studies using Medline and manual review of retrieved references, and included all population-based studies that assessed the association between overweight, body mass index (BMI25-29.9) and obesity (BMI30) and histologically confirmed ovarian cancer. Meta-analysis was restricted to those studies that expressed effect as an odds ratio (OR), risk ratio, or standardised incidence ratio and 95% confidence interval (CI). We identified 28 eligible studies, of which 16 on adult obesity and 9 on obesity in early adulthood were suitable for meta-analysis. Overall, 24 of 28 studies reported a positive association between obesity and ovarian cancer, and in 10 this reached statistical significance. The pooled effect estimate for adult obesity was 1.3 (95%CI1.1-1.5) with a smaller increased risk for overweight (OR1.2;95%CI1.0-1.3). The pooled OR was stronger among case-control studies (OR=1.5) than cohort studies (OR=1.1). Overweight/obesity in early adulthood was also associated with an increased risk of ovarian cancer. There was no evidence that the association varied for the different histological subtypes of ovarian cancer. Ovarian cancer should be added to the list of cancers likely to be related to obesity.

Adolescent↗

PubMed2004

A meta-analysis of randomized controlled studies on the effects of extended-release niacin in women.

The present meta-analysis pooled data from 5 double-blind, placebo-controlled studies in 432 patients with dyslipidemia treated with various doses of extended-release niacin. Data were analyzed for possible gender differences in response to treatment. At all doses, mean decreases in low-density lipoprotein cholesterol were greater in women than in men; differences were significant at doses of 1,000 mg (6.8% vs 0.2%, p = 0.006), 1,500 mg (11.3% vs 5.6%, p = 0.013), 2,000 mg (14.8% vs 6.9%, p = 0.010), and 3,000 mg (28.7% vs 17.7%, p = 0.006). Decreases in triglyceride levels also tended to be greater in women than in men but reached significance only at the 1,500-mg dose (28.6% vs 20.4%, p = 0.040). No similar trends or significant gender differences were noted in levels of lipoprotein(a) and high-density lipoprotein cholesterol. This meta-analysis confirms that women respond as well as men, and possibly slightly better, to treatment with extended-release niacin and that it is a safe and effective treatment option for women with dyslipidemia.

Adult↗

PubMed2003

[Non invasive ventilation for acute exacerbation of chronic obstructive pulmonary disease: a meta-analysis].

BACKGROUND AND OBJECTIVES: The purpose of this study was: 1) To determine the effect of non invasive ventilation (NIV) in chronic obstructive pulmonary disease (COPD) patients with acute respiratory failure, and 2) To find out whether there are differences in the results according to the site where ventilation in applied. PATIENTS AND METHOD: Meta-analysis of randomized controlled trials (RCTs) published included studies in MEDLINE, EMBASE, Cochrane Controled Trials Register and Teseo. Study selection included RCTs in COPD patients with acute respiratory failure with PaCO2 > 45 mmHg or pH < 7.35, with underwent NIV versus standard therapy. Mortality, rate of tracheal intubation and length of stay were analized. Individual studies were rated as to their validity and quality by two investigators using the Jadad score. A different meta-analysis was made for intensive-care unit (ICU) RCTs and wards RCTs. RESULTS: Five ICU RCTs and four ward RCTs were included. There was a reduction in hospital mortality (ICU, OR = 0.35; 95% confidence interval [CI], 0.15 to 0.83; n = 166; p = 0.02; ward, OR = 0.39; 95% CI, 0.20 to 0.76; n = 296; p = 0.005) and in the need for intubation (ICU, OR = 0.18; 95% CI, 0.10 to 0.35; n= 219; p < 0,00001; ward, OR = 0.43; IC 95%, 0.24-0.78; n = 270; p = 0.006). Length of stay was lower in the NIV group upon ICU trials (WMD, 3.7 days; 95% CI, 5.46 to 1.93 days). Only one ward RCT showed significant differences in the length of stay. Published data did not allow a meta-analysis for length of stay. CONCLUSIONS: NIV decreases mortality and the need for intubation in COPD patients with acute respiratory failure both in ICU and ward. In ICU non-invasive ventilation decreases the length of stay too.

Acute Disease↗

PubMed2000

The efficacy of thyroidectomy for Graves' disease: A meta-analysis.

BACKGROUND: Surgery for Graves' disease was largely replaced in the mid-1900s by radioiodine and antithyroid drugs, due to the belief that they were more safe and effective. Since then, thyroid surgery has improved with preoperative drug therapy and modern operative techniques. Recent clinical studies of thyroidectomy for Graves' disease may not reflect outcomes accurately because of small sample size, especially when estimating ideal thyroid remnant size. The purpose of this study was to combine modern clinical trials and use meta-analysis to determine the overall efficacy of both total (TT) and subtotal thyroidectomy (ST) for Graves' disease, compare thyroid function and complications rates of TT and ST, and determine ideal thyroid remnant size. METHODS: Meta-analysis was performed on published studies in which patients underwent either TT or ST for Graves' disease. Meta-analysis was performed by weighted least-squares linear regression. P < 0.05 was considered significant. RESULTS: There were 35 studies comprising 7241 patients. Mean follow-up was 5.6 years. Overall, persistent or recurrent hyperthyroidism occurred in 7.2% of patients. TT was performed on 538 patients and hypothyroidism occurred in all cases. ST was performed in 6703 patients, 59.7% of whom achieved euthyroidism, 25. 6% became hypothyroid, and 7.9% had either persistent or recurrent hyperthyroidism. Permanent recurrent laryngeal nerve injury occurred in 0.9% of TT patients and 0.7% of ST patients (P = NS). Permanent hypoparathyroidism occurred in 1.6% of TT patients and 1.0% of ST patients (P = NS). There was an 8.9% decrease in hypothyroidism and 6.9% increase in euthyroidism for each gram of thyroid remnant (P < 0.0001 each). CONCLUSIONS: Overall, thyroidectomy successfully treated hyperthyroidism in 92% of patients with Graves' disease. There were no cases of hyperthyroidism following TT. ST achieved a euthyroid state in almost 60% of patients with an 8% rate of persistent or recurrent hyperthyroidism. There was no significant difference in complication rates between TT and ST.

Adolescent↗

PubMed2000

A meta-analysis of prospective trials comparing percutaneous and surgical tracheostomy in critically ill patients.

STUDY OBJECTIVES: Tracheostomy is one of the most commonly performed procedures in the patient receiving long-term mechanical ventilation. While percutaneous dilational tracheostomy (PDT) is becoming increasingly utilized as an alternative to conventional surgical tracheostomy, most literature evaluating these two techniques is neither prospective nor controlled. We performed a meta-analysis of available prospective controlled studies comparing PDT and surgical tracheostomy in critically ill patients to more fully understand the relative benefits and risks of these two procedures in this population. DESIGN: Meta-analysis using Mantel-Haenszel fixed effect model. INTERVENTIONS: We performed searches of MEDLINE, Current Contents, Best Evidence, Cochrane, and HealthSTAR databases from 1985 to present to identify prospective controlled studies comparing PDT and surgical tracheostomy in critically ill patients. After establishing clinical and statistical homogeneity (Q: statistic), studies were analyzed by a Mantel-Haenszel fixed effect model. For each clinical end point examined, PDT and surgical tracheostomy were compared by calculating either absolute differences or odds ratios (ORs) with 95% confidence intervals (CIs) for continuous or discrete variables, respectively. MEASUREMENTS AND RESULTS: We pooled data from five studies (236 patients) satisfying our search criteria to analyze eight clinical end points. Operative time was shorter for PDT than surgical tracheostomy: absolute difference with 95% CI, 9. 84 min (7.83 to 10.85 min). There was no difference comparing PDT and surgical tracheostomy with respect to overall operative complication rates: OR with 95% CI, 0.732 (0.05 to 9.37). However, relative to surgical tracheostomy, PDT was associated with less perioperative bleeding (OR with 95% CI, 0.14 [0.02 to 0.39]), a lower overall postoperative complication rate (OR with 95% CI, 0.14 [0.07 to 0.29]), as well as a lower postoperative incidence of bleeding (OR with 95% CI, 0.39 [0.17 to 0.88]), and stomal infection (OR with 95% CI, 0.02 [0.01 to 0.07]). No difference was identified in days intubated prior to tracheostomy (absolute difference with 95% CI, 0.16 days [- 0.9 to 1.22 days]), overall procedure-related complications (OR with 95% CI, 0.73 [0.06 to 9.37]), or death (OR with 95% CI, 0.63 [0.18 to 2.20]) comparing these two techniques. CONCLUSIONS: Despite its popularity, there are currently only a limited number of small studies prospectively evaluating PDT and surgical tracheostomy. Our meta-analysis of these studies suggests potential advantages of PDT relative to surgical tracheostomy, including ease of performance, and lower incidence of peristomal bleeding and postoperative infection. If confirmed by additional, adequately powered prospective trials, these findings support PDT as the procedure of choice for the establishment of elective tracheostomy in the appropriately selected critically ill patient.

Blood Loss, Surgical↗

PubMed2006

Meta-analysis of the complications of laparoscopic renal surgery: comparison of procedures and techniques.

PURPOSE: We performed a meta-analysis of the literature to define the current expectations of complications during laparoscopic renal surgery. MATERIALS AND METHODS: References were searched in the MEDLINE database from 1995 to 2004 using the terms complications and laparoscopic nephrectomy. Inclusion criteria were any series with greater than 20 cases, patient age older than 16 years and any complications listed for certain procedures, including laparoscopic radical nephrectomy, HA laparoscopic radical nephrectomy, LPN, HALPN, laparoscopic donor nephrectomy, HA laparoscopic donor nephrectomy, laparoscopic simple nephrectomy, laparoscopic nephroureterectomy and retroperitoneal laparoscopic nephrectomy. A data extraction form was created to categorize major or minor complications. A 5 member panel adhered to the strict criteria and extracted data from articles that met inclusion criteria. Data were entered into a spreadsheet and a meta-analysis was performed. RESULTS: Initial review identified 73 of 405 references that were acceptable for retrieval and data extraction, of which 56 met inclusion criteria. The overall major and minor complication rates of laparoscopic renal surgery were 9.5% and 1.9%, respectively. There was a significant difference between the major complication rates of LPN and HALPN (21.0% vs 3.3%, p <0.05). CONCLUSIONS: Our results show that patients who undergo laparoscopic renal surgery may have an overall major complication rate of 9.5%. The highest major complication rate is associated with technically challenging LPN (21%). There appears to be a significantly higher wound complication rate associated with HA surgery in comparison to that of standard laparoscopy (1.9% vs 0.2%, p <0.05).

Humans↗

PubMedDate not supplied

Assortative mating in the affective disorders: a systematic review and meta-analysis.

Assortative mating, or the tendency for individuals with similar phenotypes to mate more frequently than expected by chance, has been reported for a variety of complex traits, including many neuropsychiatric disorders. Although assortative mating has been reported in affective disorders, the studies done to date have been inconclusive. This study attempts to assess the degree of assortative mating in individuals with affective disorders using systematic review and meta-analytic techniques. Studies on assortative mating in affective disorders were identified by a computerized literature search and by bibliographic assessment of published studies and reviews. Studies were selected if they had a case-control design and if they reported rates of affective disorders in the spouses of probands and controls. Of the 17 studies reviewed, six were selected for meta-analysis. All studies were blinded. Details of study design, patient characteristics, and rates of affective disorders were assessed by two independent reviewers. Twelve of the 17 studies assessed reported an increase in assortative mating. Results of the meta-analysis supported these findings, and indicated that assortative mating occurs in both bipolar disorder and major depression. Although most studies examined reported an increase in assortative mating among individuals with affective disorders, the degree of assortative mating reported varied widely. Meta-analysis with six controlled studies showed evidence for assortative mating, and suggested that the degree of assortative mating is higher for individuals with bipolar disorder than for those with major depression. These results support the previously reported findings, and may have important implications for genetic studies.

Adult↗

PubMed2003

[Levofloxacine for the treatment of pneumococcal pneumonia: results of a meta-analysis].

Levofloxacine is a fluoroquinolone presenting good anti-pneumococcal activity, including against strains with reduced sensitivity to penicillin. Four randomized controlled studies have compared the efficacy of levofloxacine versus other antibiotics (amoxacillin-clavulanic acid, amoxicillin, ceftriaxone, ceftriaxone plus cefuroxime +/- erythromycin) for the treatment of acute community-acquired pneumonia in adults. Grouping the 1,738 analyzable patients in these four studies, a meta-analysis was performed on the sub-group of 275 patients with documented pneumococcal infection (86 with bacteriemia) in order to compare the efficacy of levofloxacine with that of the comparer antibiotics. The trials were homogeneous, allowing the meta-analysis. The overall rate of clinical success was 88.6% in the levofloxacine group and 86.7% in the comparer group. The interval of confidence for the difference in the rate of estimated clinical success was between -5.65% and +9.39%. Bacteriologically, the rate of eradication was 90.2% and 90.4% respectively with an interval of confidence for the difference between -7.83% and +7.36%. The results of this meta-analysis confirmed that the efficacy of levofloxacine for the treatment of acute community-acquired pneumococcal pneumonia is not inferior to that of the comparers; the interval of confidence for the difference in the estimated rate of success did not include the breaking point of non-inferiority (-10% set for the clinical studies) and included zero.

Acute Disease↗

PubMed1995

Meta-analysis of randomized controlled trials of cranial electrostimulation. Efficacy in treating selected psychological and physiological conditions.

To clarify the diverse published results of cranial electrostimulation (CES) efficacy, we conducted an extensive literature review that identified 18 of the most carefully conducted randomized controlled trials of CES versus sham treatment. For the 14 trials that had sufficient data, we used the techniques of meta-analysis to pool the published results of treating each of four conditions: anxiety (eight trials), brain dysfunction (two trials), headache (two trials), and insomnia (two trials). Because studies utilized different outcome measures, we used an effect size method to normalize measures which we then pooled across studies within each condition. The meta-analysis of anxiety showed CES to be significantly more effective than sham treatment (p < .05). Pooling did not affect results that were individually positive (headache and pain under anesthesia) or negative (brain dysfunction and insomnia). Most studies failed to report all data necessary for meta-analysis. Moreover, in all but two trials, the therapist was not blinded and knew which patients were receiving CES or sham treatment. We strongly recommend that future trials of CES report complete data and incorporate therapist blinding to avoid possible bias.

Anxiety Disorders↗

PubMed2005

The role of G196A polymorphism in the brain-derived neurotrophic factor gene in the cause of Parkinson's disease: a meta-analysis.

The association between Parkinson's disease (PD) and the G196A polymorphism in the brain-derived neurotrophic factor (BDNF) gene has been investigated in several case-control studies, producing contradictory results: one study indicated that homozygocity of AA is associated with PD, another study produced the opposite result, whereas other studies found no association. To investigate these contradictory findings, a meta-analysis of all available association studies between the G196A polymorphism and the risk of developing PD was conducted. Four out of six identified studies included populations of East Asian descent, and two included populations of European descent (Whites). Overall, the meta-analysis of the allele contrast (A vs G) suggested large heterogeneity between studies (P=0.07, I2 =51%) and no association between G196A and the risk of developing PD: random effects odds ratio (OR)=1.00 [95% CI (0.85, 1.18)]. The sensitivity analysis (exclusion of two studies: one East Asian and one White) with the controls not in Hardy-Weinberg equilibrium showed large heterogeneity (P=0.10, I2 =52%) and no significant association: random effects OR=0.94 [95% CI (0.77, 1.15)]. The subgroup analyses for East Asians and Whites produced no significant association. In addition, the contrast of homozygotes, and the dominant and recessive models for allele A did not support a major role for this polymorphism in the pathogenesis of PD. There were no sources of bias in the selected studies, and the differential magnitude of effect in large vs small studies was not significant. The meta-analysis results suggest that the involvement of the BDNF gene in susceptibility to PD merits further exploration with larger and more rigorous population association studies.

Asian People↗

PubMed2001

Meta-analysis of studies using selective alpha1-blockers in patients with hypertension and type 2 diabetes.

This meta-analysis of published studies evaluated the effect of selective alpha1-blockers on lipid and carbohydrate profiles and blood pressure (BP) as well as tolerability in patients with hypertension and type 2 diabetes. Publications identified via MEDLINE were used. Text and bibliographies of retrieved articles were examined for additional references. Clinical trials with a randomised comparative structure (placebo and active treatment arms) and controlled studies with other structures were included. Of the 27 citations identified, 22 studies were selected for inclusion, and five were rejected. Efficacy and safety data, lipid and carbohydrate profiles, and study and patient characteristics were extracted by two investigators independently. The mean pooled results showed beneficial effects of selective alpha1-blockers on total serum cholesterol (TC), high-density lipoprotein (HDL) cholesterol, and systolic and diastolic BP. The results also showed doxazosin had beneficial effects on fasting glucose levels, insulin sensitivity, TC, HDL cholesterol, low-density lipoprotein (LDL) cholesterol, HDL/TC ratio, and systolic and diastolic BP. The risk difference was equivalent between the alpha1-blocker group and the control group for postural hypotension or syncope. This meta-analysis demonstrates a number of favourable effects of therapy with selective alpha1-blockers in hypertensive patients with type 2 diabetes. These agents provide an effective modality for reducing BP, with favourable effects on lipid, no deterioration in glycaemic control, and little risk of orthostatic hypotension.

Adrenergic alpha-Antagonists↗