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Breast cancer is the most common cancer worldwide. Recent studies suggest that organic solvent exposure could be closely related to breast cancer, although the evidence remains controversial. Thus, we evaluated existing epidemiological evidence for the association between occupational solvent exposure and breast cancer. PubMed, Embase, and Cochrane Library were searched to identify published case–control and cohort studies that addressed occupational exposure to organic solvents and breast cancer, up to April, 2021. Meta-analyses using random-effects models were conducted to obtain the pooled odds ratios (OR) and 95% confidence intervals (CI) on the incidence of breast cancer in relation to occupational exposure. The pooled OR of breast cancer among workers exposed to organic solvents overall was 1.18 (95%CI, 1.11 ~ 1.25; I2 = 76.3%; 24 studies), compared to those with no exposure. After stratification by menopause and study location, it was revealed that the association between occupational exposure to organic solvents and the risk of breast cancer in postmenopausal women (OR, 1.35; 95% CI, 1.09 ~ 1.67; I2 = 73.4%; 7 studies) was significant, and there was also a clear association in workers in Europe (OR, 1.21; 95% CI, 1.12 ~ 1.32; I2 = 82.9%; 13 studies). We observed a significant association between occupational exposure to organic solvents and breast cancer in both cohort and case–control studies. [ABSTRACT FROM AUTHOR]

Study Question: Does sexual intercourse in the implantation time window (5-9 days after ovulation) reduce fecundability?Summary Answer: After adjustment for intercourse in the fecund window and clustering by couple, there was no association between intercourse in the implantation time window and fecundity.What Is Known Already: Previous research has suggested an association between intercourse in the peri-implantation time window (5-9 days after estimated ovulation) and reduced fecundability.Study Design, Size, Duration: We used data from the FERTILI study, a prospective observational study conducted in five European countries, with data collected from 1992 to 1996.Participants/materials, Setting, Methods: Women who were experienced in fertility awareness tracking kept a daily diary of cervical mucus observations, basal body temperature measurements, coitus and clinically identified pregnancy. We estimated the day of ovulation as cycle length minus 13 days. From 661 women, 2606 cycles had intercourse during the fecund window (from 5 days before to 3 days after the estimated day of ovulation), resulting in 418 pregnancies (conception cycles). An established Bayesian fecundability model was used to estimate the fecundability ratio (FR) of peri-implantation intercourse on fecundability, while adjusting for each partner's age, prior pregnancy, the couple's probability of conception and intercourse pattern(s). We conducted sensitivity analyses estimating ovulation as cycle length minus 12 days, or alternatively, as the peak day of estrogenic cervical mucus.Main Results and the Role Of Chance: There was no effect of peri-implantation intercourse on fecundability: adjusted FR for three or more acts of peri-implantation intercourse versus none: 1.00, 95% credible interval: 0.76-1.13. Results were essentially the same with sensitivity analyses. There was an inverse relationship between frequency of intercourse in the fecund window and intercourse in the peri-implantation window.Limitations, Reasons For Caution: Women with known subfertility were excluded from this study. Many couples in the study were avoiding pregnancy during much of the study, so 61% of otherwise eligible cycles in the database were not at meaningful risk of pregnancy and did not contribute to the analysis. Some couples may not have recorded all intercourse.Wider Implications Of the Findings: We believe the current balance of evidence does not support a recommendation for avoiding intercourse in the peri-implantation period among couples trying to conceive.Study Funding/competing Interest(s): No external funding. The authors have no potential competing interests.Trial Registration Number: N/A. [ABSTRACT FROM AUTHOR]

Background Postoperative atrial fibrillation (POAF) is a common arrhythmia following cardiac surgery and is associated with increased health-care costs, complications, and mortality. The etiology of POAF is incompletely understood and its prediction remains suboptimal. Using data from published studies, we performed a systemic review and meta-analysis to identify preoperative clinical risk factors associated with patients at increased risk of POAF. Methods A systematic search of PubMed, MEDLINE, and EMBASE databases was performed. Results Twenty-four studies that reported univariate analysis results regarding POAF risk factors, published from 2001 to May 2017, were included in this meta-analysis with a total number of 36,834 subjects. Eighteen studies were performed in the United States and Europe and 16 studies were prospective cohort studies. The standardized mean difference (SMD) between POAF and non-POAF groups was significantly different (reported as [SMD: 95% confidence interval, CI]) for age (0.55: 0.47–0.63), left atrial diameter (0.45: 0.15–0.75), and left ventricular ejection fraction (0.30: 0.14–0.47). The pooled odds ratios (ORs) (reported as [OR: 95% CI]) demonstrated that heart failure (1.56: 1.31–1.96), chronic obstructive pulmonary disease (1.36: 1.13–1.64), hypertension (1.29: 1.12–1.48), and myocardial infarction (1.18: 1.05–1.34) were significant predictors of POAF incidence, while diabetes was marginally significant (1.06: 1.00–1.13). Conclusion The present analysis suggested that older age and history of heart failure were significant risk factors for POAF consistently whether the included studies were prospective or retrospective datasets. [ABSTRACT FROM AUTHOR]

MRI Assessment of Ablation-Induced Scarring in Atrial Fibrillation Background There is limited knowledge on the extent and location of scarring that results from catheter ablation and its role in suppressing atrial fibrillation (AF). We examined the effect of atrial fibrosis and ablation-induced scarring on catheter ablation outcomes in AF. Methods We conducted a prospective multicenter study that enrolled 329 AF patients presenting for catheter ablation. Delayed enhancement magnetic resonance imaging (DE-MRI) of the left atrium was obtained preablation. Scarring was evaluated in 177 patients with a DE-MRI scan obtained 90 days postablation. We evaluated residual fibrosis, defined as preablation atrial fibrosis not covered by ablation scar. The primary outcome was freedom from recurrent atrial arrhythmia. Results In the analysis cohort of 177 patients, preablation fibrosis was 18.7 ± 8.7% of the atrial wall. Ablation aimed at pulmonary vein (PV) isolation was performed in 163 patients (92.1%). Ablation-induced scar averaged 10.6 ± 4.4% of the atrial wall. Scarring completely encircled all 4 PVs only in 12 patients (7.3%). Residual fibrosis was calculated at 15.8 ± 8.0%. At 325 days follow-up, 35% of patients experienced recurrent arrhythmia. Multivariable Cox proportional hazards models demonstrated that baseline atrial fibrosis (HR and 95% CIs) (1.09 [1.06-1.12], P < 0.001) and residual fibrosis (1.09 [1.05-1.13], P < 0.001) were associated with atrial arrhythmia recurrence, while PV encirclement and overall scar were not. Conclusions Catheter ablation of AF targeting PVs rarely achieves permanent encircling scar in the intended areas. Overall atrial fibrosis present at baseline and residual fibrosis uncovered by ablation scar are associated with recurrent arrhythmia. [ABSTRACT FROM AUTHOR]