-
BMJ (Clinical Research Ed.) Mar 2022To systematically compare the effect of direct oral anticoagulants and low molecular weight heparin for thromboprophylaxis on the benefits and harms to patients... (Meta-Analysis)
Meta-Analysis
Benefits and harms of direct oral anticoagulation and low molecular weight heparin for thromboprophylaxis in patients undergoing non-cardiac surgery: systematic review and network meta-analysis of randomised trials.
OBJECTIVE
To systematically compare the effect of direct oral anticoagulants and low molecular weight heparin for thromboprophylaxis on the benefits and harms to patients undergoing non-cardiac surgery.
DESIGN
Systematic review and network meta-analysis of randomised controlled trials.
DATA SOURCES
Medline, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL), up to August 2021.
REVIEW METHODS
Randomised controlled trials in adults undergoing non-cardiac surgery were selected, comparing low molecular weight heparin (prophylactic (low) or higher dose) with direct oral anticoagulants or with no active treatment. Main outcomes were symptomatic venous thromboembolism, symptomatic pulmonary embolism, and major bleeding. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used for network meta-analyses. Abstracts and full texts were screened independently in duplicate. Data were abstracted on study participants, interventions, and outcomes, and risk of bias was assessed independently in duplicate. Frequentist network meta-analysis with multivariate random effects models provided odds ratios with 95% confidence intervals, and GRADE (grading of recommendations, assessment, development, and evaluation) assessments indicated the certainty of the evidence.
RESULTS
68 randomised controlled trials were included (51 orthopaedic, 10 general, four gynaecological, two thoracic, and one urological surgery), involving 45 445 patients. Low dose (odds ratio 0.33, 95% confidence interval 0.16 to 0.67) and high dose (0.19, 0.07 to 0.54) low molecular weight heparin, and direct oral anticoagulants (0.17, 0.07 to 0.41) reduced symptomatic venous thromboembolism compared with no active treatment, with absolute risk differences of 1-100 per 1000 patients, depending on baseline risks (certainty of evidence, moderate to high). None of the active agents reduced symptomatic pulmonary embolism (certainty of evidence, low to moderate). Direct oral anticoagulants and low molecular weight heparin were associated with a 2-3-fold increase in the odds of major bleeding compared with no active treatment (certainty of evidence, moderate to high), with absolute risk differences as high as 50 per 1000 in patients at high risk. Compared with low dose low molecular weight heparin, high dose low molecular weight heparin did not reduce symptomatic venous thromboembolism (0.57, 0.26 to 1.27) but increased major bleeding (1.87, 1.06 to 3.31); direct oral anticoagulants reduced symptomatic venous thromboembolism (0.53, 0.32 to 0.89) and did not increase major bleeding (1.23, 0.89 to 1.69).
CONCLUSIONS
Direct oral anticoagulants and low molecular weight heparin reduced venous thromboembolism compared with no active treatment but probably increased major bleeding to a similar extent. Direct oral anticoagulants probably prevent symptomatic venous thromboembolism to a greater extent than prophylactic low molecular weight heparin.
SYSTEMATIC REVIEW REGISTRATION
PROSPERO CRD42018106181.
Topics: Anticoagulants; Hemorrhage; Heparin, Low-Molecular-Weight; Humans; Network Meta-Analysis; Postoperative Complications; Pulmonary Embolism; Randomized Controlled Trials as Topic; Surgical Procedures, Operative; Treatment Outcome; Venous Thromboembolism
PubMed: 35264372
DOI: 10.1136/bmj-2021-066785 -
The Cochrane Database of Systematic... Feb 2018The optimal treatment of superficial thrombophlebitis (ST) of the legs remains poorly defined. While improving or relieving the local painful symptoms, treatment should... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The optimal treatment of superficial thrombophlebitis (ST) of the legs remains poorly defined. While improving or relieving the local painful symptoms, treatment should aim at preventing venous thromboembolism (VTE), which might complicate the natural history of ST. This is the third update of a review first published in 2007.
OBJECTIVES
To assess the efficacy and safety of topical, medical, and surgical treatments for ST of the leg in improving local symptoms and decreasing thromboembolic complications.
SEARCH METHODS
For this update, the Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register (March 2017), CENTRAL (2017, Issue 2), and trials registries (March 2017). We handsearched the reference lists of relevant papers and conference proceedings.
SELECTION CRITERIA
Randomised controlled trials (RCTs) evaluating topical, medical, and surgical treatments for ST of the legs that included people with a clinical diagnosis of ST of the legs or objective diagnosis of a thrombus in a superficial vein.
DATA COLLECTION AND ANALYSIS
Two authors assessed the trials for inclusion in the review, extracted the data, and assessed the quality of the studies. Data were independently extracted from the included studies and any disagreements resolved by consensus. We assessed the quality of the evidence using the GRADE approach.
MAIN RESULTS
We identified three additional trials (613 participants), therefore this update considered 33 studies involving 7296 people with ST of the legs. Treatment included fondaparinux; rivaroxaban; low molecular weight heparin (LMWH); unfractionated heparin (UFH); non-steroidal anti-inflammatory drugs (NSAIDs); compression stockings; and topical, intramuscular, or intravenous treatment to surgical interventions such as thrombectomy or ligation. Only a minority of trials compared treatment with placebo rather than an alternative treatment and many studies were small and of poor quality. Pooling of the data was possible for few outcomes, and none were part of a placebo-controlled trial. In one large, placebo-controlled RCT of 3002 participants, subcutaneous fondaparinux was associated with a significant reduction in symptomatic VTE (risk ratio (RR) 0.15, 95% confidence interval (CI) 0.04 to 0.50; moderate-quality evidence), ST extension (RR 0.08, 95% CI 0.03 to 0.22; moderate-quality evidence), and ST recurrence (RR 0.21, 95% CI 0.08 to 0.54; moderate-quality evidence) relative to placebo. Major bleeding was infrequent in both groups with very wide CIs around risk estimate (RR 0.99, 95% CI 0.06 to 15.86; moderate-quality evidence). In one RCT on 472 high-risk participants with ST, fondaparinux was associated with a non-significant reduction of symptomatic VTE compared to rivaroxaban 10 mg (RR 0.33, 95% CI 0.03 to 3.18; low-quality evidence). There were no major bleeding events in either group (low-quality evidence). In another placebo-controlled trial, both prophylactic and therapeutic doses of LMWH (prophylactic: RR 0.44, 95% CI 0.26 to 0.74; therapeutic: RR 0.46, 95% CI 0.27 to 0.77) and NSAIDs (RR 0.46, 95% CI 0.27 to 0.78) reduced the extension (low-quality evidence) and recurrence of ST (low-quality evidence) in comparison to placebo, with no significant effects on symptomatic VTE (low-quality evidence) or major bleeding (low-quality evidence). Overall, topical treatments improved local symptoms compared with placebo, but no data were provided on the effects on VTE and ST extension. Surgical treatment combined with elastic stockings was associated with a lower VTE rate and ST progression compared with elastic stockings alone. However, the majority of studies that compared different oral treatments, topical treatments, or surgery did not report VTE, ST progression, adverse events, or treatment adverse effects.
AUTHORS' CONCLUSIONS
Prophylactic dose fondaparinux given for 45 days appears to be a valid therapeutic option for ST of the legs for most people. The evidence on topical treatment or surgery is too limited and does not inform clinical practice about the effects of these treatments in terms of VTE. Further research is needed to assess the role of rivaroxaban and other direct oral factor-X or thrombin inhibitors, LMWH, and NSAIDs; the optimal doses and duration of treatment in people at various risk of recurrence; and whether a combination therapy may be more effective than single treatment. Adequately designed and conducted studies are required to clarify the role of topical and surgical treatments.
Topics: Anti-Inflammatory Agents, Non-Steroidal; Anticoagulants; Factor Xa Inhibitors; Fondaparinux; Hemorrhage; Heparin, Low-Molecular-Weight; Humans; Polysaccharides; Randomized Controlled Trials as Topic; Rivaroxaban; Stockings, Compression; Thrombectomy; Thromboembolism; Thrombophlebitis; Venous Thromboembolism
PubMed: 29478266
DOI: 10.1002/14651858.CD004982.pub6 -
Journal of Hematology & Oncology May 2022International clinical practice guidelines have progressively endorsed direct oral anticoagulants (DOACs) as an alternative to low-molecular-weight heparins (LMWHs)... (Meta-Analysis)
Meta-Analysis
Direct oral anticoagulant versus low molecular weight heparin for the treatment of cancer-associated venous thromboembolism: 2022 updated systematic review and meta-analysis of randomized controlled trials.
International clinical practice guidelines have progressively endorsed direct oral anticoagulants (DOACs) as an alternative to low-molecular-weight heparins (LMWHs) monotherapy for the initial and long-term treatment of cancer-associated thrombosis (CAT). Several new randomized controlled trials (RCTs) have recently reported additional results on the safety and efficacy of DOACs in this setting. We performed an updated meta-analysis of all publicly available data from RCTs comparing DOACs with LMWHs for the treatment of CAT. Six RCTs enrolling 3690 patients with CAT were included. Compared with LMWHs, DOACs significantly decreased the risk of CAT recurrence (RR, 0.67; 95%CI, 0.52-0.85), with a non-significant increase in the risk of major bleeding (RR, 1.17; 95%CI, 0.82-1.67), a significant increase in the risk of clinically relevant nonmajor bleeding (RR 1.66; 95%CI, 1.31-2.09) and no difference in all-cause mortality rates. These results increase the level of certainty of available evidence supporting the use of DOACs as an effective and safe option for the treatment of CAT in selected cancer patients.
Topics: Anticoagulants; Hemorrhage; Heparin, Low-Molecular-Weight; Humans; Neoplasms; Randomized Controlled Trials as Topic; Thrombosis; Venous Thromboembolism
PubMed: 35598026
DOI: 10.1186/s13045-022-01289-1 -
Scandinavian Journal of Surgery : SJS :... Jun 2021Acute mesenteric venous thrombosis accounts for up to 20% of all patients with acute mesenteric ischemia in high-income countries. Acute mesenteric venous thrombosis is...
BACKGROUND AND AIMS
Acute mesenteric venous thrombosis accounts for up to 20% of all patients with acute mesenteric ischemia in high-income countries. Acute mesenteric venous thrombosis is nowadays relatively more often diagnosed with intravenous contrast-enhanced computed tomography in the portal phase than at explorative laparotomy No high-quality comparative studies between anticoagulation alone, endovascular therapy, or surgery exists. The aim of the present systematic review was to offer a contemporary overview on management.
MATERIALS AND METHODS
Eleven relevant published original studies with series of at least ten patients were retrieved from a Pub Med search between 2015 and 2020 using the Medical Subject Heading term "mesenteric venous thrombosis."
RESULTS
When MVT is diagnosed early, immediate anticoagulation with either unfractionated heparin or subcutaneous low-molecular-weight heparin should commence. Surgeons need to be aware of the importance to scrutinize the computed tomography images themselves for assessment of secondary intestinal abnormalities to mesenteric venous thrombosis and the risk of bowel resection and worse prognosis. Progression toward peritonitis is an indication for explorative laparotomy and assessment of bowel viability. Frank transmural small bowel necrosis should be resected and bowel anastomosis may be delayed for several days until second look. Meanwhile, intravenous full-dose unfractionated heparin should be given at the end of the first operation. Postoperative major intra-abdominal or gastrointestinal bleeding occurs rarely, but the heparin effect can instantaneously be reversed by . Patients who do not improve during conservative therapy with anticoagulation alone but without developing peritonitis may be subjected to endovascular therapy in expert centers. When the patient's intestinal function has recovered, with or without bowel resection, switch from parenteral unfractionated heparin or low-molecular-weight heparin therapy to oral anticoagulation can be performed. There is a trend that direct oral anticoagulants are increasingly used instead of vitamin K antagonists. Up to now, direct oral anticoagulants have been shown to be equally effective with the same rate of bleeding complications. Patients with no strong permanent trigger factor for mesenteric venous thrombosis such as intra-abdominal cancer should undergo blood screening for inherited and acquired thrombophilia.
CONCLUSION
Early diagnosis with emergency computed tomography with intravenous contrast-enhancement and imaging in the portal phase and anticoagulation therapy is necessary to be able to have a succesful non-operative succesful course.
Topics: Anticoagulants; Heparin; Humans; Mesenteric Ischemia; Mesenteric Veins; Venous Thrombosis
PubMed: 33118463
DOI: 10.1177/1457496920969084 -
Chest May 2023The management of patients who are receiving chronic oral anticoagulation therapy and require an elective surgery or an invasive procedure is a common clinical scenario. (Meta-Analysis)
Meta-Analysis
BACKGROUND
The management of patients who are receiving chronic oral anticoagulation therapy and require an elective surgery or an invasive procedure is a common clinical scenario.
RESEARCH QUESTION
What is the best available evidence to support the development of American College of Chest Physicians guidelines on the perioperative management of patients who are receiving long-term vitamin K agonist (VKA) or direct oral anticoagulant (DOAC) and require elective surgery or procedures?
STUDY DESIGN AND METHODS
A literature search including multiple databases from database inception through July 16, 2020, was performed. Meta-analyses were conducted when appropriate.
RESULTS
In patients receiving VKA (warfarin) undergoing elective noncardiac surgery, shorter (< 3 days) VKA interruption is associated with an increased risk of major bleeding. In patients who required VKA interruption, heparin bridging (mostly with low-molecular-weight heparin [LMWH]) was associated with a statistically significant increased risk of major bleed, representing a very low certainty of evidence (COE). Compared with DOAC interruption 1 to 4 days before surgery, continuing DOACs may be associated with higher risk of bleeding demonstrated in some, but not all studies. In patients who needed DOAC interruption, bridging with LMWH may be associated with a statistically significant increased risk of bleeding, representing a low COE.
INTERPRETATION
The certainty in the evidence supporting the perioperative management of anticoagulants remains limited. No high-quality evidence exists to support the practice of heparin bridging during the interruption of VKA or DOAC therapy for an elective surgery or procedure, or for the practice of interrupting VKA therapy for minor procedures, including cardiac device implantation, or continuation of a DOAC vs short-term interruption of a DOAC in the perioperative period.
Topics: Humans; Heparin, Low-Molecular-Weight; Anticoagulants; Heparin; Warfarin; Fibrinolytic Agents; Hemorrhage; Vitamin K; Administration, Oral
PubMed: 36462533
DOI: 10.1016/j.chest.2022.11.032 -
Taiwanese Journal of Obstetrics &... Mar 2020Due to the morbidity and mortality of mothers and fetuses developed by preeclampsia, preventive approaches have always been taken into account in high risk individuals....
Due to the morbidity and mortality of mothers and fetuses developed by preeclampsia, preventive approaches have always been taken into account in high risk individuals. Systematic review studies contribute to make a better decision about the results of such studies. Accordingly, this study strived to systematically study the factors effective in the prevention of preeclampsia. The MEDLINE, ISI Web of Science, PubMed, Scopus, Google Scholar, and Proquest databases were systematically reviewed between January 2000 and May 2019. The quality of the studies was analyzed using the CONSORT checklist. A study was conducted on 29 quality interventional studies; 28 of which were RCT type, and on various factors such as anticoagulants (heparin, enoxaparin, Dalteparin and Nadroparin), aspirin, paravastatin, nitric oxide, yoga, micronutrients Such as l-Arginine, Folic Acid, Vitamin E and C, Phytonutrient, Lycopene and Vitamin D alone or in combination with Calcium. The results of this study showed that low molecular weight heparin, enoxaparin, PETN, yoga, L arginine, folic acid, vitamin D prevented preeclampsia alone or combined with calcium.
Topics: Arginine; Calcium; Drug Therapy, Combination; Enoxaparin; Female; Folic Acid; Heparin, Low-Molecular-Weight; Humans; Pentaerythritol Tetranitrate; Pre-Eclampsia; Pregnancy; Prenatal Care; Vitamin D; Yoga
PubMed: 32127134
DOI: 10.1016/j.tjog.2020.01.002 -
BMJ (Clinical Research Ed.) Jul 2022To assess the benefits and harms of different types and doses of anticoagulant drugs for the prevention of venous thromboembolism in patients who are acutely ill and... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
To assess the benefits and harms of different types and doses of anticoagulant drugs for the prevention of venous thromboembolism in patients who are acutely ill and admitted to hospital.
DESIGN
Systematic review and network meta-analysis.
DATA SOURCES
Cochrane CENTRAL, PubMed/Medline, Embase, Web of Science, clinical trial registries, and national health authority databases. The search was last updated on 16 November 2021.
ELIGIBILITY CRITERIA FOR SELECTING STUDIES
Published and unpublished randomised controlled trials that evaluated low or intermediate dose low-molecular-weight heparin, low or intermediate dose unfractionated heparin, direct oral anticoagulants, pentasaccharides, placebo, or no intervention for the prevention of venous thromboembolism in acutely ill adult patients in hospital.
MAIN OUTCOME MEASURES
Random effects, bayesian network meta-analyses used four co-primary outcomes: all cause mortality, symptomatic venous thromboembolism, major bleeding, and serious adverse events at or closest timing to 90 days. Risk of bias was also assessed using the Cochrane risk-of-bias 2.0 tool. The quality of evidence was graded using the Confidence in Network Meta-Analysis framework.
RESULTS
44 randomised controlled trials that randomly assigned 90 095 participants were included in the main analysis. Evidence of low to moderate quality suggested none of the interventions reduced all cause mortality compared with placebo. Pentasaccharides (odds ratio 0.32, 95% credible interval 0.08 to 1.07), intermediate dose low-molecular-weight heparin (0.66, 0.46 to 0.93), direct oral anticoagulants (0.68, 0.33 to 1.34), and intermediate dose unfractionated heparin (0.71, 0.43 to 1.19) were most likely to reduce symptomatic venous thromboembolism (very low to low quality evidence). Intermediate dose unfractionated heparin (2.63, 1.00 to 6.21) and direct oral anticoagulants (2.31, 0.82 to 6.47) were most likely to increase major bleeding (low to moderate quality evidence). No conclusive differences were noted between interventions regarding serious adverse events (very low to low quality evidence). When compared with no intervention instead of placebo, all active interventions did more favourably with regard to risk of venous thromboembolism and mortality, and less favourably with regard to risk of major bleeding. The results were robust in prespecified sensitivity and subgroup analyses.
CONCLUSIONS
Low-molecular-weight heparin in an intermediate dose appears to confer the best balance of benefits and harms for prevention of venous thromboembolism. Unfractionated heparin, in particular the intermediate dose, and direct oral anticoagulants had the least favourable profile. A systematic discrepancy was noted in intervention effects that depended on whether placebo or no intervention was the reference treatment. Main limitations of this study include the quality of the evidence, which was generally low to moderate due to imprecision and within-study bias, and statistical inconsistency, which was addressed post hoc.
SYSTEMATIC REVIEW REGISTRATION
PROSPERO CRD42020173088.
Topics: Anticoagulants; Bayes Theorem; Hemorrhage; Heparin; Heparin, Low-Molecular-Weight; Hospitals; Humans; Network Meta-Analysis; Randomized Controlled Trials as Topic; Thrombosis; Venous Thromboembolism
PubMed: 35788047
DOI: 10.1136/bmj-2022-070022 -
The Lancet. Oncology Oct 2019Venous thromboembolism (VTE) is the second leading cause of death in patients with cancer. These patients are at a high risk of VTE recurrence and bleeding during...
Venous thromboembolism (VTE) is the second leading cause of death in patients with cancer. These patients are at a high risk of VTE recurrence and bleeding during anticoagulant therapy. The International Initiative on Thrombosis and Cancer is an independent academic working group aimed at establishing a global consensus for the treatment and prophylaxis of VTE in patients with cancer. The International Initiative on Thrombosis and Cancer last updated its evidence-based clinical practice guidelines in 2016 with a free, web-based mobile phone application, which was subsequently endorsed by the International Society on Thrombosis and Haemostasis. The 2019 International Initiative on Thrombosis and Cancer clinical practice guidelines, which are based on a systematic review of the literature published up to December, 2018, are presented along with a Grading of Recommendations Assessment Development and Evaluation scale methods, with the support of the French National Cancer Institute. These guidelines were reviewed by an expanded international advisory committee and endorsed by the International Society on Thrombosis and Haemostasis. Results from head-to-head clinical trials that compared direct oral anticoagulant with low-molecular-weight heparin are also summarised, along with new evidence for the treatment and prophylaxis of VTE in patients with cancer.
Topics: Anticoagulants; Central Venous Catheters; Factor Xa Inhibitors; Fondaparinux; Heparin, Low-Molecular-Weight; Humans; Neoplasms; Vena Cava Filters; Venous Thromboembolism; Vitamin K
PubMed: 31492632
DOI: 10.1016/S1470-2045(19)30336-5 -
Environmental Pollution (Barking, Essex... Sep 2023Phthalates are chemicals widely used in plastic-based consumer products, and human exposure is universal. They are classified as endocrine disruptors, and specific... (Meta-Analysis)
Meta-Analysis Review
Phthalates are chemicals widely used in plastic-based consumer products, and human exposure is universal. They are classified as endocrine disruptors, and specific phthalate metabolites have been associated with an increased risk of cardiometabolic diseases. The aim of this study was to assess the association between phthalate exposure and the metabolic syndrome in the general population. A comprehensive literature search was performed in four databases (Web of Science, Medline, PubMed, and Scopus). We included all the observational studies that evaluate the association between phthalate metabolites and the metabolic syndrome available until January 31st, 2023. Pooled Odds Ratios (OR) and their 95% confidence intervals were calculated by using the inverse-variance weighted method. Nine cross-sectional studies and 25,365 participants aged from 12 to 80 were included. Comparing extreme categories of phthalate exposure, the pooled ORs for the metabolic syndrome were: 1.08 (95% CI, 1.02-1.16, I = 28%) for low molecular weight phthalates, and 1.11 (95% CI, 1.07-1.16, I = 7%) for high molecular weight phthalates. For individual phthalate metabolites, the pooled ORs that achieved statistical significance were: 1.13 (95% CI, 1.00-1.27, I = 24%) for MiBP; 1.89 (95% CI, 1.17-3.07, I = 15%) for MMP in men; 1.12 (95% CI, 1.00-1.25, I = 22%) for MCOP; 1.09 (95% CI, 0.99-1.20, I = 0%) for MCPP; 1.16 (95% CI, 1.05-1.28, I = 6%) for MBzP; and 1.16 (95% CI, 1.09-1.24, I = 14%) for DEHP (including ΣDEHP and its metabolites). In conclusion, both low molecular weight and high molecular weight phthalates were associated with an 8 and 11% higher prevalence of the MetS, respectively. The exposure to six specific phthalate metabolites was associated with a higher prevalence of the MetS.
Topics: Male; Humans; Metabolic Syndrome; Environmental Pollutants; Cross-Sectional Studies; Phthalic Acids; Plastics; Environmental Exposure
PubMed: 37328121
DOI: 10.1016/j.envpol.2023.121957 -
American Journal of Obstetrics and... Feb 2022Evidence on the impact of low-molecular-weight heparin, alone or in combination with low-dose aspirin, for the prevention for preeclampsia in high-risk patients is... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Evidence on the impact of low-molecular-weight heparin, alone or in combination with low-dose aspirin, for the prevention for preeclampsia in high-risk patients is conflicting.
OBJECTIVE
We conducted a meta-analysis of studies published to assess the effectiveness of low-molecular-weight heparin for the prevention of preeclampsia and other placenta-related complications in high-risk women.
DATA SOURCES
A systematic search was performed to identify relevant studies, using the databases PubMed and Cochrane Central Register of Controlled Trials, without publication time restrictions.
STUDY ELIGIBILITY CRITERIA
Randomized controlled trials comparing treatment with low-molecular-weight heparin or unfractionated heparin (with or without low-dose aspirin), in high-risk women, defined as either history of preeclampsia, intrauterine growth restriction, fetal demise, or miscarriage or being at high risk after first-trimester screening of preeclampsia.
STUDY APPRAISAL AND SYNTHESIS METHODS
The systematic review was conducted according to the Cochrane Handbook guidelines. The primary outcome was the development of preeclampsia. We performed prespecified subgroup analyses according to combination with low-dose aspirin, low-molecular-weight heparin type, gestational age when treatment was started, and study population (patients with thrombophilia, at high risk of preeclampsia or miscarriage). Secondary outcomes included small for gestational age, perinatal death, miscarriage, and placental abruption. Pooled odds ratios with 95% confidence intervals were calculated using a random-effects model. Quality of evidence was assessed using the grading of recommendations assessment, development, and evaluation methodology.
RESULTS
A total of 15 studies (2795 participants) were included. In high-risk women, treatment with low-molecular-weight heparin was associated with a reduction in the development of preeclampsia (odds ratio, 0.62; 95% confidence interval, 0.43-0.90; P=.010); small for gestational age (odds ratio, 0.61; 95% confidence interval, 0.44-0.85; P=.003), and perinatal death (odds ratio, 0.49; 95% confidence interval, 0.25-0.94; P=.030). This reduction was stronger if low-molecular-weight heparin was started before 16 weeks' gestation (13 studies, 2474 participants) for preeclampsia (odds ratio, 0.55; 95% confidence interval, 0.39-0.76; P=.0004). When only studies including low-dose aspirin as an intervention were analyzed (6 randomized controlled trials, 920 participants), a significant reduction was observed in those with combined treatment (low-molecular-weight heparin plus low-dose aspirin) compared with low-dose aspirin alone (odds ratio, 0.62; 95% confidence interval, 0.41-0.95; P=.030). Overall, adverse events were neither serious nor significantly different. Quality of evidence ranged from very low to moderate, mostly because of the lack of blinding, imprecision, and inconsistency.
CONCLUSION
Low-molecular-weight heparin use was associated with a significant reduction in the risk of preeclampsia and other placenta-mediated complications in high-risk women and when treatment was started before 16 weeks' gestation. Combined treatment with low-dose aspirin was associated with a significant reduction in the risk of preeclampsia compared with low-dose aspirin alone. However, there exists important clinical and statistical heterogeneity, and therefore, these results merit confirmation in large well-designed clinical trials.
Topics: Anticoagulants; Aspirin; Drug Therapy, Combination; Female; Fetal Growth Retardation; Gestational Age; Heparin, Low-Molecular-Weight; Humans; Infant, Newborn; Infant, Small for Gestational Age; Platelet Aggregation Inhibitors; Pre-Eclampsia; Pregnancy
PubMed: 34301348
DOI: 10.1016/j.ajog.2020.11.006