Arterial and venous thrombosis are caused by a number of thrombogenic risk factors, among them are: dehydration with haemoconcentration, use of pharmacological stimulators, frequent injuries of the musculoskeletal system, an immobilisation at long-distance travel, use of oestrogen contraceptives, and congenital abnormalities affecting the anatomy of the venis [1]. Cases of sharp coronary thrombosis in marathon runners and venous thromboembolism in triathletes have been described in the literature [2-4]. It has been shown that mutations in a factor the V Leiden (FVL) and FII 20210A prothrombin in a heterozygotic state significantly increase the risk for thrombosis in the general population. However, whether those mutations are associated with thrombophilia in endurance athletes is unknown.

To examine the prevalence of prothrombotic mutations (FVL and FII 220210A) in Russian elite endurance athletes compared to the general population.

264 endurance athletes (mean age = 26.5, SD = 10.3) and 295 unrelated sedentary controls (mean age = 31.3, SD = 10.4) participated in the study. The endurance athletes group included cross-country skiers and biathlonists (n = 62), triathlonists (n = 18), walkers (n = 14), ice hockey players (n = 152), 5Km/10Km long distance skaters (n = 14), ≥5 Km runners (n = 3), and one bicycle racer. 88 athletes are winners and prize-winners of the international competitions (”elite group”). All participants were self-reported unrelated Caucasians for ≥3 generations. Written informed consent and information on diseases of cardiovascular system and pathology of haemostasis were received from all the participants. Buccal epithelium or peripheral blood was used to isolate genomic DNA with the GeneJET™ Genomic DNA Purification Kit (Thermo Fisher Scientific Inc.). Genotyping of the FVL and FII 220210A mutations was performed using TaqMan® SNP genotyping assays with a StepOne™ Real-Time PCR System (Thermo Fisher Scientific Inc.). For replication purpose, 30% of the samples were analysed twice. Positive control samples (heterozygotes on FVL and FII 20210A) were included in each experiment. Statistical analysis was performed with IBM SPSS Statistics 21.

None of the participants had the burdened thrombotic anamnesis. None of the athletes and controls carried the FVL and FII 220210A pathological mutation. Interestingly, higher levels of heterozygotes of prothrombotic mutations were found in the endurance athletes, but it has not reached the statistical significance threshold (0.05). The genotype frequencies are presented in Table 1.

In conclusion, the prevalence of the FVL and FII 20210A prothrombotic mutations in Russian elite endurance athletes is slightly higher (not significant) than in sedentary controls. Multi-centre approach to increase the sample size is required to detect the influence of a rare mutation on the athletic phenotype.

References

1. Adams M, Fell J, Williams A. Exercise causing thrombosis. Phys Sportsmed. 2009 Dec;37(4):124–30

2. Albano AJ, Thompson PD, Kapur NK. Acute coronary thrombosis in Boston marathon runners. N Engl J Med. 2012 Jan 12;366(2):184–5

3. Hull CM, Hopkins CL, Purdy NJ, Lloyd RC, Harris JA. A case of unprovoked venous thromboembolism in a marathon athlete presenting atypical sequelae: What are the chances? Scand J Med Sci Sports. 2015 Oct;25(5):699–705

4. Tao K, Davenport M. Deep venous thromboembolism in a triathlete. J Emerg Med. 2010 Apr;38(3):351–3