Physical activity in patients with deep venous thrombosis: a systematic review

Six-month exercise training program to treat post-thrombotic syndrome: a randomized controlled two-centre trial

BACKGROUND

Exercise training may have the potential to improve post-thrombotic syndrome, a frequent, chronic complication of deep venous thrombosis. We conducted a randomized controlled two-centre pilot trial to assess the feasibility of a multicentre-based evaluation of a six-month exercise training program to treat post-thrombotic syndrome and to obtain preliminary data on the effectiveness of such a program.

METHODS

Patients were randomized to receive exercise training (a six-month trainer-supervised program) or control treatment (an education session with monthly phone follow-ups). Levels of eligibility, consent, adherence and retention were used as indicators of study feasibility. Primary outcomes were change from baseline to six months in venous disease-specific quality of life (as measured using the Venous Insufficiency Epidemiological and Economic Study Quality of Life [VEINES-QOL] questionnaire) and severity of post-thrombotic syndrome (as measured by scores on the Villalta scale) in the exercise training group versus the control group, assessed by t tests. Secondary outcomes were change in generic quality of life (as measured using the Short-Form Health Survey-36 [SF-36] questionnaire), category of severity of post-thrombotic syndrome, leg strength, leg flexibility and time on treadmill.

RESULTS

Of 95 patients with post-thrombotic syndrome, 69 were eligible, 43 consented and were randomized, and 39 completed the study. Exercise training was associated with improvement in VEINES-QOL scores (exercise training mean change 6.0, standard deviation [SD] 5.1 v. control mean change 1.4, SD 7.2; difference 4.6, 95% CI 0.54 to 8.7; p = 0.027) and improvement in scores on the Villalta scale (exercise training mean change -3.6, SD 3.7 v. control mean change -1.6, SD 4.3; difference -2.0, 95% CI -4.6 to 0.6; p = 0.14). Most secondary outcomes also showed greater improvement in the exercise training group.

INTERPRETATION

Exercise training may improve post-thrombotic syndrome. It would be feasible to definitively evaluate exercise training as a treatment for post-thrombotic syndrome in a large multicentre trial.

Physical activity interventions to improve daily walking activity in cancer survivors

Background

Cancer patients may benefit from physical exercise programs. It is unclear, however, how sustained levels of physical activity are best achieved in this population. A systematic review was performed to summarize the current evidence of the effect of physical activity interventions on daily walking activity enhancement in cancer survivors, and to review the literature for its methodological quality.

Methods

A search in Medline, PEDro and the Cochrane databases was performed for English literature citations (randomized controlled trials; 'RCTs'). In a first step, one reviewer abstracted data from the included studies on patients, physical activity interventions and outcomes. Two independent reviewers reviewed the methodological quality of these studies. Data were pooled using random-effects calculations.

Results

Our search identified 201 citations. Five RCTs that reported changes in daily step activity over time were identified, and were reviewed for methodological quality and substantive results. The median score across studies for methodological quality based on the PEDro criteria was 8. These 5 RCTs evaluated 660 participants with a mean age of 53.6 (SD 4.2) years. The mean change in daily step activity for patients with a physical exercise intervention was 526 daily steps (SD 537), with a range from -92 to 1299 daily steps. The data of three studies reporting the effect of combined physical activity and counseling on daily walking activity in breast cancer survivors were pooled, however; the I² was 79%, indicating statistical heterogeneity between the three trials.

Conclusion

The 5 RCTs reviewed were of good methodological quality. Together they suggest that combined physical activity and counseling improves daily step activity in (breast) cancer survivors. Studies that define a step goal appear to be more effective in improving daily walking activity than studies that do not do so. However, the current results should be interpreted with caution because of the observed clinical and statistical heterogeneity. Future studies are warranted to evaluate the effects of goal targeted physical activity, with or without counseling, on daily walking in various cancer populations.

Exercise causing thrombosis

Thrombophilia refers to the increased tendency to form blood clots (thrombosis), which is a major cause of morbidity and mortality. Thrombosis is associated with various chronic conditions such as cancer, diabetes, renal disorders, and cardiovascular disease. The incidence and associated complications of thrombosis are likely to increase significantly in the next few decades because of aging populations. Regular exercise has been proposed to decrease the risk of developing thrombosis, although there are inconsistent data from studies investigating its effects, with reports of both increased and decreased thrombotic risk across a variety of subject cohorts. Confounders such as age, gender, hormonal variations, physical activity, underlying disease and treatment, and body composition also contribute to the difficulty in assessing and defining the precise effects of exercise in preventing thrombotic events. However, there is evidence suggesting that physical activity is beneficial for reducing thrombotic risk in younger individuals and those with chronic conditions. This article aims to summarize the known risk factors for thrombosis and briefly review the benefits of exercise in the general population. Furthermore, this article highlights the additional factors in a cohort of individuals that would (at first) appear unlikely to be at risk of thrombosis--elite athletes.

Effect of early physical activity on long-term outcome after venous thrombosis

OBJECTIVE

To determine if the level of self-reported physical activity 1 month after deep vein thrombosis (DVT) is associated with the risk of post-thrombotic syndrome (PTS) in the first 2 years post-DVT.

DESIGN

Prospective cohort study.

SETTING

Multicenter study (8 hospitals).

PARTICIPANTS

Patients presenting with objectively diagnosed acute DVT to 8 hospitals in Quebec and Ontario, Canada.

ASSESSMENT OF RISK FACTORS

We used validated questionnaires to measure physical activity (Godin questionnaire) and venous disease severity [generic physical quality of life (SF-36 PCS scale) or VEINES-QOL]. We adjusted for potential confounding effects of age, sex, and body mass index. We used multiple imputation to account for missing data.

MAIN OUTCOME MEASURES

Post-thrombotic syndrome (validated Villalta scale).

RESULTS

For the 387 patients enrolled, univariate analysis suggested no association between 1-month activity and risk of PTS. After adjusting for missing data and potential confounders, there was no evidence of a trend toward increasing risk of PTS with increasing physical activity [1.65 (95% confidence interval, 0.87-3.14) for mild-moderate activity and 1.35 (95% confidence interval, 0.69-2.67) for high activity]. The results were similar when PTS was dichotomized as none/mild versus moderate/severe. Finally, patients with PTS had lower levels of activity at 2 years post-DVT.

CONCLUSIONS

The level of self-reported exercise in the first month post-DVT is not associated with an increased risk of PTS in the first 2 years after DVT. Post-thrombotic syndrome is associated with decreased levels of physical activity 2 years after DVT.

What do we know of post-thrombotic syndrome? Current status of post-thrombotic syndrome in adults

The post-thrombotic syndrome (PTS) is a common but not completely understood and rarely studied sequela of an acute deep vein thrombosis. The influence of several risk factors on the incidence or severity of PTS is controversial. The therapeutic options for PTS are still limited. Appropriate medical compression stockings can reduce the incidence (-50 %) as well as the severity of PTS. In the case of severe, symptomatic PTS, they should be worn lifelong. As PTS is a chronic and often progressive disease, patients need regular clinical follow-up and encouragement to continuously wear their compression therapy. New strategies for treating PTS are needed.

What happens after venous thromboembolism?

Venous thromboembolism (VTE) comprises deep vein thrombosis (DVT) with or without symptomatic pulmonary embolus (PE). The incidence of a first episode of VTE is 1.5 per 1000 person-years [1] (J Thromb Haemost, 2007;5:692-9) with a per-person lifetime incidence of 5% [2] (Arch Intern Med 1998;158:585-93). The risk of recurrence after DVT and PE is similar but the pattern of recurrence tends to reflect the initial event, for example recurrence with PE is more common in patients with previous PE [3] (Circulation 2003;107:122-30). At least 50% of patients, who present with symptomatic DVT, have asymptomatic PE and conversely, a majority presenting with symptomatic PE have asymptomatic DVT [3] (Circulation 2003;107:122-30). This suggests that whilst DVT and PE are manifestations of the same pathology, the phenotypic expression of the disease is predetermined. This may be an important consideration for long-term anticoagulant therapy as the risk of fatal PE is the greatest in patients with previous PE [4] (Ann Intern Med 2007;147:766-74). At present, the only factor reported to be associated with the pattern of VTE is the factor V Leiden mutation [5] (Thromb Haemost 1999;81:345-8). This suggests that the kinetics of thrombin generation and the resulting fibrinolytic response may influence clot structure and likelihood of embolization.