Relationship between body mass index, risk of venous thromboembolism and pulmonary embolism: A systematic review and dose-response meta-analysis of cohort studies among four million participants

Abstract

Background: The relationship between body mass index (BMI) and risk of venous thromboembolism (VTE) and pulmonary embolism (PE) is a controversial issue. This dose-response meta-analysis was performed to investigate the association between BMI and risk of VTE and PE incidence based on cohort studies. Method: A comprehensive systematic search was conducted up to August 2019 in MEDLINE/PubMed, SCOPUS, and Cochrane. DerSimonian and Laird random-effects models were run to estimate combined hazard ratios (HRs) with 95 confidence intervals (CIs). Dose-response analysis was also carried out based on BMI values. Results: Eleven articles with 16 arms and 3,910,747 participants were eligible for inclusion in this systematic review and meta-analysis. Pooled results showed a positive association between BMI and risk of VTE in the obese participants compared to participants classified in the normal BMI category (HR: 1.62, 95 CI: 1.29-2.04, I-2 = 95). Furthermore, results showed a significant association between lower BMI (underweight versus normal BMI category) and reduced risk of PE (HR: 0.80, 95 CI: 0.70-0.92, I-2 = 9) and higher risk of PE in obese versus normal BMI participants (HR: 2.24, 95 CI: 1.93-2.60, I-2 = 0). There was a significant linear relationship between BMI and risk of VTE (p < 0.001) and PE (p < 0.001). Conclusions: This systematic review and dose-response meta-analysis with 3,910,747 participants highlights obesity as a significant risk factor related to the incidence of VTE and PE.