The impact of different intensities of physical activity on the risk of venous thromboembolism: A Mendelian randomization study.

Vigorous physical activity was significantly associated with a reduced risk of venous thromboembolism.

• OR = 0.727, 95% CI = 0.576-0.920, P < .017
• The primary statistical method employed was the inverse variance weighted (IVW) approach
• The significance threshold was set at P < .017 (Bonferroni correction for 3 exposures tested)
• Genetic instruments for physical activity were sourced from the UK Biobank (1,335,561 participants)

Light physical activity showed only suggestive evidence of association with reduced VTE risk at a relaxed significance level.

• OR = 0.778, 95% CI = 0.610-0.994, P = .045 by the inverse variance weighted method
• This association did not meet the pre-specified significance threshold of P < .017
• The association was described as 'suggestive evidence' at the relaxed significance level of 0.017 < P < .05

Moderate physical activity did not show a statistically significant association with VTE risk.

• P > .017, not achieving statistical significance at the pre-specified threshold
• The association also did not achieve significance at the relaxed level (P > .05)
• Three intensities of PA were evaluated: light, moderate, and vigorous

The study used a 2-sample Mendelian randomization design with large datasets from UK Biobank and FinnGen.

• VTE data came from 412,181 individuals from the FinnGen study R10 data release
• Physical activity data included 1,335,561 participants from the UK Biobank across 3 intensity levels
• Robustness was evaluated using MR-Egger regression, weighted median, and MR pleiotropy residual sum and outlier (MR-PRESSO) tests