Investigating the risks of cardiovascular disease among premenopausal women using oral contraceptive: a protocol for a systematic review and meta-analysis

Effect of combined oral contraceptive on cardiorespiratory function and immune activation in premenopausal women involved in exercise: A systematic review protocol

BACKGROUND

The use of combined oral contraceptive (COC) is common among women of reproductive age despite the potential risk of them developing thrombotic events. There is a need to understand how COC affects cardiorespiratory function and markers of immune activation in premenopausal women involved in exercise. This highlights a need for a systematic review to enhance our understanding of how the use of COC affects cardiovascular health in premenopausal women subjected to exercise.

METHOD

This systematic review protocol was prepared following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P) 2015 statement. An extensive search of relevant literature by two independent reviewers will be conducted through the EBSCOhost interface to access databases such as MEDLINE, EMBASE, and CINAHL. Other health sources, including Cochrane CENTRAL, unpublished studies and grey literature, will also be searched. The search will include all studies that report the effect of COC on essential parameters of cardiorespiratory function and markers of immune activation in premenopausal women involved in exercise. All included studies will be appraised using appraisal tools, while appropriate extraction tools will be used for data extraction. Where possible, eligible studies will be pooled for meta-analysis. If statistical pooling is not feasible, our findings will be presented in a narrative format. The certainty of evidence will be assessed using the Grading of Recommendations, Assessment, Development and Evaluation Assessment (GRADE) tool.

TRIAL REGISTRATION

PROSPERO registration number: CRD42021265257.

Is the multinational, surveillance PRO-E2 study informative for all countries? The Italian data on VTE and contraceptive effectiveness

PURPOSE

To evaluate whether the thromboembolic risk and contraceptive effectiveness of NOMAC-E2 observed in the PRO-E2 study can be extended to each participating country, as lifestyle, cardiovascular risk factors and prescribing habits may differ geographically. This analysis was performed on the PRO-E2 Italian subpopulation, where smoking habit and women over 35 years were more prevalent compared with the overall study population.

MATERIALS AND METHODS

Data from NOMAC-E2 or levonorgestrel-containing COCs (COCLNG) new users were descriptively analysed. Incidence rates of thrombosis (events/10,000 women-years [WY]) and the Pearl Index (pregnancies/100 WY) were calculated.

RESULTS

Overall, 11,179 NOMAC-E2 and 8,504 COCLNG users were followed up to 2 years (34,869 WY). The NOMAC-E2 cohort included more women over 35 vs. COCLNG (37.7% vs. 31.8%; p = 0.001). A comparable low risk of combined deep venous thrombosis of lower extremities (DVT) and pulmonary embolism (PE) was observed in NOMAC-E2 (1.7/10,000 WY; 95% CI: 0.21-6.2) and COCLNG users (6.6/10,000 WY; 95% CI: 2.4-14.4). Similar results were obtained by considering all thromboembolic events (VTE). Unintended pregnancies did not differ between NOMAC-E2 (0.12/100 WY; 95% CI: 0.06-0.21) and COCLNG (0.15/100 WY; 95% CI: 0.08-0.26) cohorts.

CONCLUSION

Despite the higher age and tobacco use, findings from the Italian subpopulation were broadly consistent with overall PRO-E2 results, confirming a similar low thromboembolic risk and high contraceptive effectiveness of NOMAC-E2 and COCLNG.

SHORT CONDENSATION

This subgroup analysis of the PRO-E2 study provides comprehensive epidemiological data on the use of combined oral contraceptives in a large Italian cohort, with a higher prevalence of women over 35 years and smokers. The study confirms the low thromboembolic risk and high contraceptive effectiveness of NOMAC-E2 pill.

A Systematic Review of Exercise Therapy for Bowel Preparation: Evidence to Guide Practice

This systematic review aims to evaluate (1) the effectiveness of exercise therapy in bowel preparation for colonoscopy, and (2) the characteristics of exercise programs for bowel preparation. Systematic searches were done in PubMed, EMBASE, the Cochrane Library, Web of Science, and CINAHL from inception to November 2022. Randomized controlled trials and quasi-experimental studies assessing the efficacy of exercise during bowel preparation were included in this review. Two reviewers independently assessed the methodological quality using a modified Downs and Black checklist. A narrative synthesis was conducted. A total of five studies (1,109 participants) were included in this review. In all eligible studies, the characteristics of the exercise programs varied and included mainly two types of exercise (walking and yoga), various amount of exercise (3,000-10,000 steps or 0.5-1.9 hours), and two exercise timing (during and 1 hour after taking the laxative). Available evidence indicated that exercise therapy is effective in improving the quality of bowel preparation. However, there was insufficient high-quality evidence to conclude the effects on procedure-related indicators, adverse events, and willingness to repeat preparation. Exercise should be recommended as an important part of routine bowel preparation for patients undergoing colonoscopy to improve the quality of bowel preparation. More rigorous studies focusing on the effects on procedure-related indicators, adverse events, and willingness to repeat preparation are needed. To ensure the effectiveness and safety of the intervention, it is critical to establish a standard, well-structured exercise program for bowel preparation.

Investigating cardiovascular risk in premenopausal women on oral contraceptives: Systematic review with meta-analysis

Background

The use of oral contraceptives (OCs) is associated with an increased risk of cardiovascular events such as arterial and venous thrombosis (VTE). Cardiovascular diseases (CVDs) are the leading cause of death worldwide, with low- and middle-income nations accounting for over three-quarter of CVD deaths. The aim of this systematic review is to provide a comprehensive synthesis of the available evidence on the link between OC use and CVD risk in premenopausal women and to further assess the role of geographic disparities in the reported prevalence of CVD risk in women on OCs.

Methods

A comprehensive search of databases such as MEDLINE, Academic Search Complete, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Health Source: Nursing/Academic Edition was conducted, right from the inception to the present, by using the EBSCOhost search engine. The Cochrane Central Register of Clinical trials (CENTRAL) was also searched to augment relevant sources of information. OpenGrey, which is a repository of information providing open access to bibliographical references, was searched and the reference list of the selected studies was also scanned. The potential risk of bias of the included studies was assessed using the modified Downs and Black checklist. Data analysis was performed using the Review Manager (RevMan) version 5.3.

Results

We included 25 studies that comprised 3,245 participants, of which 1,605 (49.5%) are OC users, while 1,640 (50.5%) are non-OC users. A total of 15 studies were included for meta-analysis, and the overall pooled estimates suggested a significant increase in the traditional cardiovascular risk variables [standardized mean difference (SMD) = 0.73, (0.46, 0.99) (Z = 5.41, p < 0.001)] and little to no difference in endothelial activation among OC users when compared with non-OC users [SMD = -0.11, (-0.81, 0.60) (Z = 0.30, p = 0.76)]. Europe [SMD = 0.03, (-0.21, 0.27), (Z = 0.25 p = 0.88)] had the least effect size, while North America had the highest effect size [SMD = 1.86, (-0.31, 4.04), (Z = 1.68 p = 0.09)] for CVD risk in OC users when compared with non-OC users.

Conclusion

The use of OCs suggests a significant increase in the prevalence of traditional cardiovascular risk variables with little to no difference in the risk of endothelial dysfunction when compared with non-OC users, and the magnitude of CVD risks varies across different geographical regions.

Registration and protocol

This systematic review was registered in the international prospective register of systematic reviews (PROSPERO) under the registration number: CRD42020216169.