Antioxidants for female subfertility.
M.G. Showell, R. Mackenzie‐Proctor, V. Jordan, and R.J. Hart, “Antioxidants for Female Subfertility,” Cochrane Database of Systematic Reviews, no. 8 (2020): CD007807, https://doi.org/10.1002/14651858.CD007807.pub4 This Editorial Note is for the above article, published online on August 27, 2020, in Cochrane Library (cochranelibrary.com), and has been issued by the Publisher, John Wiley & Sons Ltd, in agreement with Cochrane. The Editorial note has been agreed due to concerns discovered by the Cochrane managing editor regarding the retraction of six studies in the Review (Badawy et al. 2006, 10.1016/j.fertnstert.2006.02.097; El Refaeey et al. 2014, 10.1016/j.rbmo.2014.03.011; El Sharkwy & Abd El Aziz 2019a, https://doi.org/10.1002/ijgo.12902; Gerli et al. 2007, https://doi.org/10.26355/eurrev_202309_33752, full text: https://europepmc.org/article/MED/18074942; Ismail et al. 2014, http://dx.doi.org/10.1016/j.ejogrb.2014.06.008; Hashemi et al. 2017, https://doi.org/10.1080/14767058.2017.1372413). In addition, expressions of concern have been published for two studies (Jamilian et al. 2018, https://doi.org/10.1007/s12011-017-1236-3; Zadeh Modarres 2018, https://doi.org/10.1007/s12011-017-1148-2). The retracted studies will be moved to the Excluded Studies table, and their impact on the review findings will be investigated and acted on accordingly in a future update. Initial checks indicate that removal of the six retracted studies did not make an appreciable difference to the results. Likewise, the studies for which Expressions of Concern were issued will be moved to the Awaiting classification table; they did not report any review outcomes, so removal will have no impact on the review findings.
A couple may be considered to have fertility problems if they have been trying to conceive for over a year with no success. This may affect up to a quarter of all couples planning a child. It is estimated that for 40% to 50% of couples, subfertility may result from factors affecting women. Antioxidants are thought to reduce the oxidative stress brought on by these conditions. Currently, limited evidence suggests that antioxidants improve fertility, and trials have explored this area with varied results. This review assesses the evidence for the effectiveness of different antioxidants in female subfertility.
To determine whether supplementary oral antioxidants compared with placebo, no treatment/standard treatment or another antioxidant improve fertility outcomes for subfertile women.
We searched the following databases (from their inception to September 2019), with no language or date restriction: Cochrane Gynaecology and Fertility Group (CGFG) specialised register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL and AMED. We checked reference lists of relevant studies and searched the trial registers.
We included randomised controlled trials (RCTs) that compared any type, dose or combination of oral antioxidant supplement with placebo, no treatment or treatment with another antioxidant, among women attending a reproductive clinic. We excluded trials comparing antioxidants with fertility drugs alone and trials that only included fertile women attending a fertility clinic because of male partner infertility.
We used standard methodological procedures expected by Cochrane. The primary review outcome was live birth; secondary outcomes included clinical pregnancy rates and adverse events.
We included 63 trials involving 7760 women. Investigators compared oral antioxidants, including: combinations of antioxidants, N-acetylcysteine, melatonin, L-arginine, myo-inositol, carnitine, selenium, vitamin E, vitamin B complex, vitamin C, vitamin D+calcium, CoQ10, and omega-3-polyunsaturated fatty acids versus placebo, no treatment/standard treatment or another antioxidant. Only 27 of the 63 included trials reported funding sources. Due to the very low-quality of the evidence we are uncertain whether antioxidants improve live birth rate compared with placebo or no treatment/standard treatment (odds ratio (OR) 1.81, 95% confidence interval (CI) 1.36 to 2.43; P < 0.001, I2 = 29%; 13 RCTs, 1227 women). This suggests that among subfertile women with an expected live birth rate of 19%, the rate among women using antioxidants would be between 24% and 36%. Low-quality evidence suggests that antioxidants may improve clinical pregnancy rate compared with placebo or no treatment/standard treatment (OR 1.65, 95% CI 1.43 to 1.89; P < 0.001, I2 = 63%; 35 RCTs, 5165 women). This suggests that among subfertile women with an expected clinical pregnancy rate of 19%, the rate among women using antioxidants would be between 25% and 30%. Heterogeneity was moderately high. Overall 28 trials reported on various adverse events in the meta-analysis. The evidence suggests that the use of antioxidants makes no difference between the groups in rates of miscarriage (OR 1.13, 95% CI 0.82 to 1.55; P = 0.46, I2 = 0%; 24 RCTs, 3229 women; low-quality evidence). There was also no evidence of a difference between the groups in rates of multiple pregnancy (OR 1.00, 95% CI 0.63 to 1.56; P = 0.99, I2 = 0%; 9 RCTs, 1886 women; low-quality evidence). There was also no evidence of a difference between the groups in rates of gastrointestinal disturbances (OR 1.55, 95% CI 0.47 to 5.10; P = 0.47, I2 = 0%; 3 RCTs, 343 women; low-quality evidence). Low-quality evidence showed that there was also no difference between the groups in rates of ectopic pregnancy (OR 1.40, 95% CI 0.27 to 7.20; P = 0.69, I2 = 0%; 4 RCTs, 404 women). In the antioxidant versus antioxidant comparison, low-quality evidence shows no difference in a lower dose of melatonin being associated with an increased live-birth rate compared with higher-dose melatonin (OR 0.94, 95% CI 0.41 to 2.15; P = 0.89, I2 = 0%; 2 RCTs, 140 women). This suggests that among subfertile women with an expected live-birth rate of 24%, the rate among women using a lower dose of melatonin compared to a higher dose would be between 12% and 40%. Similarly with clinical pregnancy, there was no evidence of a difference between the groups in rates between a lower and a higher dose of melatonin (OR 0.94, 95% CI 0.41 to 2.15; P = 0.89, I2 = 0%; 2 RCTs, 140 women). Three trials reported on miscarriage in the antioxidant versus antioxidant comparison (two used doses of melatonin and one compared N-acetylcysteine versus L-carnitine). There were no miscarriages in either melatonin trial. Multiple pregnancy and gastrointestinal disturbances were not reported, and ectopic pregnancy was reported by only one trial, with no events. The study comparing N-acetylcysteine with L-carnitine did not report live birth rate. Very low-quality evidence shows no evidence of a difference in clinical pregnancy (OR 0.81, 95% CI 0.33 to 2.00; 1 RCT, 164 women; low-quality evidence). Low quality evidence shows no difference in miscarriage (OR 1.54, 95% CI 0.42 to 5.67; 1 RCT, 164 women; low-quality evidence). The study did not report multiple pregnancy, gastrointestinal disturbances or ectopic pregnancy. The overall quality of evidence was limited by serious risk of bias associated with poor reporting of methods, imprecision and inconsistency.
In this review, there was low- to very low-quality evidence to show that taking an antioxidant may benefit subfertile women. Overall, there is no evidence of increased risk of miscarriage, multiple births, gastrointestinal effects or ectopic pregnancies, but evidence was of very low quality. At this time, there is limited evidence in support of supplemental oral antioxidants for subfertile women.
Showell MG
,Mackenzie-Proctor R
,Jordan V
,Hart RJ
... -
《Cochrane Database of Systematic Reviews》
Interventions to prevent surgical site infection in adults undergoing cardiac surgery.
Surgical site infection (SSI) is a common type of hospital-acquired infection and affects up to a third of patients following surgical procedures. It is associated with significant mortality and morbidity. In the United Kingdom alone, it is estimated to add another £30 million to the cost of adult cardiac surgery. Although generic guidance for SSI prevention exists, this is not specific to adult cardiac surgery. Furthermore, many of the risk factors for SSI are prevalent within the cardiac surgery population. Despite this, there is currently no standard of care for SSI prevention in adults undergoing cardiac surgery throughout the preoperative, intraoperative and postoperative periods of care, with variations in practice existing throughout from risk stratification, decontamination strategies and surveillance.
Primary objective: to assess the clinical effectiveness of pre-, intra-, and postoperative interventions in the prevention of cardiac SSI.
(i) to evaluate the effects of SSI prevention interventions on morbidity, mortality, and resource use; (ii) to evaluate the effects of SSI prevention care bundles on morbidity, mortality, and resource use.
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE (Ovid, from inception) and Embase (Ovid, from inception) on 31 May 2021.
gov and the WHO International Clinical Trials Registry Platform (ICTRP) were also searched for ongoing or unpublished trials on 21 May 2021. No language restrictions were imposed.
We included RCTs evaluating interventions to reduce SSI in adults (≥ 18 years of age) who have undergone any cardiac surgery.
We followed the methods as per our published Cochrane protocol. Our primary outcome was surgical site infection. Our secondary outcomes were all-cause mortality, reoperation for SSI, hospital length of stay, hospital readmissions for SSI, healthcare costs and cost-effectiveness, quality of life (QoL), and adverse effects. We used the GRADE approach to assess the certainty of evidence.
A total of 118 studies involving 51,854 participants were included. Twenty-two interventions to reduce SSI in adults undergoing cardiac surgery were identified. The risk of bias was judged to be high in the majority of studies. There was heterogeneity in the study populations and interventions; consequently, meta-analysis was not appropriate for many of the comparisons and these are presented as narrative summaries. We focused our reporting of findings on four comparisons deemed to be of great clinical relevance by all review authors. Decolonisation versus no decolonisation Pooled data from three studies (n = 1564) using preoperative topical oral/nasal decontamination in all patients demonstrated an uncertain direction of treatment effect in relation to total SSI (RR 0.98, 95% CI 0.70 to 1.36; I2 = 0%; very low-certainty evidence). A single study reported that decolonisation likely results in little to no difference in superficial SSI (RR 1.35, 95% CI 0.84 to 2.15; moderate-certainty evidence) and a reduction in deep SSI (RR 0.36, 95% CI 0.17 to 0.77; high-certainty evidence). The evidence on all-cause mortality from three studies (n = 1564) is very uncertain (RR 0.66, 95% CI 0.24 to 1.84; I2 = 49%; very low-certainty evidence). A single study (n = 954) demonstrated that decolonisation may result in little to no difference in hospital readmission for SSI (RR 0.80, 95% CI 0.44 to 1.45; low-certainty evidence). A single study (n = 954) reported one case of temporary discolouration of teeth in the decolonisation arm (low-certainty-evidence. Reoperation for SSI was not reported. Tight glucose control versus standard glucose control Pooled data from seven studies (n = 880) showed that tight glucose control may reduce total SSI, but the evidence is very uncertain (RR 0.41, 95% CI 0.19 to 0.85; I2 = 29%; numbers need to treat to benefit (NNTB) = 13; very-low certainty evidence). Pooled data from seven studies (n = 3334) showed tight glucose control may reduce all-cause mortality, but the evidence is very uncertain (RR 0.61, 95% CI 0.41 to 0.91; I2 = 0%; very low-certainty evidence). Based on four studies (n = 2793), there may be little to no difference in episodes of hypoglycaemia between tight control vs. standard control, but the evidence is very uncertain (RR 2.12, 95% CI 0.51 to 8.76; I2 = 72%; very low-certainty evidence). No studies reported superficial/deep SSI, reoperation for SSI, or hospital readmission for SSI. Negative pressure wound therapy (NPWT) versus standard dressings NPWT was assessed in two studies (n = 144) and it may reduce total SSI, but the evidence is very uncertain (RR 0.17, 95% CI 0.03 to 0.97; I2 = 0%; NNTB = 10; very low-certainty evidence). A single study (n = 80) reported reoperation for SSI. The relative effect could not be estimated. The certainty of evidence was judged to be very low. No studies reported superficial/deep SSI, all-cause mortality, hospital readmission for SSI, or adverse effects. Topical antimicrobials versus no topical antimicrobials Five studies (n = 5382) evaluated topical gentamicin sponge, which may reduce total SSI (RR 0.62, 95% CI 0.46 to 0.84; I2 = 48%; NNTB = 32), superficial SSI (RR 0.60, 95% CI 0.37 to 0.98; I2 = 69%), and deep SSI (RR 0.67, 95% CI 0.47 to 0.96; I2 = 5%; low-certainty evidence. Four studies (n = 4662) demonstrated that topical gentamicin sponge may result in little to no difference in all-cause mortality, but the evidence is very uncertain (RR 0.96, 95% CI 0.65 to 1.42; I2 = 0%; very low-certainty evidence). Reoperation for SSI, hospital readmission for SSI, and adverse effects were not reported in any included studies.
This review provides the broadest and most recent review of the current evidence base for interventions to reduce SSI in adults undergoing cardiac surgery. Twenty-one interventions were identified across the perioperative period. Evidence is of low to very low certainty primarily due to significant heterogeneity in how interventions were implemented and the definitions of SSI used. Knowledge gaps have been identified across a number of practices that should represent key areas for future research. Efforts to standardise SSI outcome reporting are warranted.
Cardiothoracic Interdisciplinary Research Network
,Rogers LJ
,Vaja R
,Bleetman D
,Ali JM
,Rochon M
,Sanders J
,Tanner J
,Lamagni TL
,Talukder S
,Quijano-Campos JC
,Lai F
,Loubani M
,Murphy GJ
... -
《Cochrane Database of Systematic Reviews》