The principal objective of this study was to examine the effect of intense physical exercise on menstrual blood loss in women with Type I von Willebrand disease (vWD). First, we investigated the effect of exercise on the level of the von Willebrand protein (which is deficient in the disease) in a pre-test post-test quasi-experiment conducted on a single group of 40 healthy adult pre-menopausal female volunteers recruited from Sainte-Justine Hospital in Montreal between October and December, 2001. The von Willebrand protein (vWF:Ag), coagulation Factor VIII (FVIII:C), bleeding time (BT), coagulation time (aPTT) and several markers of exercise intensity (sweat sodium, lactate, noradrenaline, adrenaline) were measured before and after a standardized exercise session. The significance of the change in these values with exercise was assessed using a paired Student's t-test. The exercise markers were explored as potential predictors of the exercise-related change in vWF:Ag using multiple linear regression. Results showed that there was an absolute mean increase of 0.30 (95% confidence interval (95% CI) 0.23-0.37) and 0.60 (95% CI 0.44-0.76) in vWF:Ag and FVIILC, respectively, and a significant shortening of the BT and aPTT due to exercise. The change in the sweat sodium collected from patches applied to the forearm during exercise (a marker of exercise intensity) was found to be a significant predictor of the change in vWF:Ag induced by exercise (regression coefficient = 0.05 (95% CI 0.01-0.09). Changes of 1, 5 and 10 units in sodium were associated with average changes of 0.05, 0.26 and 0.52, respectively, in vWF:Ag from baseline (mean 0.83 U/ml). Next, we set out to assess the feasibility and acceptability of a 4-period randomized crossover trial in order to evaluate the effectiveness of exercise in reducing the menstrual blood flow in women with Type I vWD. The methods and protocol of this feasibility study are outlined in this thesis and issues related to patient recruitment, compliance and withdrawals are addressed. The strengths and pitfalls of the crossover design feasibility study are discussed and revisions for the definitive trial are recommended.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.19416 |
| Date | January 2003 |
| Creators | Winikoff, Rochelle |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Epidemiology and Biostatistics) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 002009089, Theses scanned by McGill Library. |
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