e13096 Background: Several studies have reported the association between atrial fibrillation (AF) and malignant cancer. Recently, results from a large cohort within the Women’s Health Study showed increased incident risk of breast, colon and lung cancer in patients with AF. Therefore, we performed a systematic review to assess the available evidence and a meta-analysis to define the strength of this association. Methods: MEDLINE, Cochrane and Scopus databases were searched for all prospective studies that reported the association between AF and presence of cancer. The HR for incident risk of common cancers was recorded (Breast, Lung, Colorectal) in patients with and without AF. Lung cancer was excluded because the data required for the analysis was not consistently reported. The DerSimonian-Laird random effects meta-analysis was performed to derive pooled Hazard Ratio (HR) estimates for incident risk of colorectal and breast cancer in patients with AF. Q-test was used to assess between-study heterogeneity; I2 statistic was computed to expresses the percentage of the total observed variability due to study heterogeneity. Results: A total of 390,479 participants in 3 prospective studies were included in the analysis. Mean age of participants was 66.3 ± 6.5 with mean follow up for 12.6 years. Patients with atrial fibrillation had 27% more risk of developing colorectal cancer [HR 1.27 (1.07-1.51) p < 0.005, I2= 73%] and 14% more risk of developing breast cancer [HR 1.14 (1.03-1.26) p = 0.01, I2= 37%] as compared to those without atrial fibrillation. Applying these hazard ratios to age adjusted yearly incidence ratios from 2000-2015, one in 5824 new onset AF cases will develop CRC and one in 7474 new onset AF cases will develop breast cancer. Conclusions: There is small but statistically significant increase in risk of subsequent diagnosis of colorectal or breast cancer diagnosis in patients with AF. Shared risk factors such as old age or systemic disease processes may explain this association. While the results of this analysis raise interesting questions for future search, these results should not be used as basis to initiate cancer screening for an occult cancer in a patient with AF.
Association of One-Carbon Metabolism-Related Vitamins (Folate, B6, B12), Homocysteine and Methionine With the Risk of Lung Cancer: Systematic Review and Meta-Analysis
