Studying Hypercoagulability in Hip Fracture Patients as Determined by Thrombelastography

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Abstract

Hip fractures are the most devastating manifestation of osteoporosis with high venous thromboembolic (VTE) rates reported following surgery. Currently, there is no guideline consensus on the optimal duration of pharmacologic thromboprophylaxis or medication choice. Furthermore, some patients develop VTE despite being on anticoagulation. Thrombelastography (TEG) is a whole-blood viscoelastic hemostatic assay that has the potential to identify hypercoagulable patients at risk for developing VTE. The purpose of this study was to understand the utility of TEG analysis to quantify hypercoagulability and ensuing VTE risk in patients with hip fracture. Serial TEG analysis was performed in a cohort of patients with hip fracture every 24- hours from admission until post-operative day (POD) five, then at two and six weeks postoperatively. Hypercoagulability was quantified using a TEG maximal amplitude (MA) threshold over 65 mm. Multivariable logistic regression evaluated associations between elevated MA values and patient and surgical factors. In total, 121 patients (88 female) with a median age of 81 (range = 53 – 96) were recruited. Although admission TEG analysis revealed normal coagulation status (MA<65mm), patients transitioned to a hypercoagulable state by POD 3. Hypercoagulability peaked two weeks post-operatively. Furthermore, most patients remained hypercoagulable six weeks post-operatively, despite discontinuing anticoagulation one to two weeks prior. On admission, female sex and the presence of chronic kidney disease were associated with hypercoagulability (MA>65mm). Post-operatively, reduced mobility and treatment with arthroplasty were associated with hypercoagulability (MA>65mm). Results from this study support further investigation into individualized extended thromboprophylaxis regimens in patients with hip fracture. Additionally, TEG-identified patient and surgical factors associated with hypercoagulability should be given further consideration to mitigate VTE risk and in the development of future hip fracture specific VTE risk prediction models.

Cited Works (8)

Year	Entry
2009	Brauer CA, Coca-Perraillon M, Cutler DM, Rosen AB. Incidence and mortality of hip fractures in the United States. JAMA. October 14, 2009;302(10):1573-1579.
2000	Alem AM, Sherrard DJ, Gillen DL, Weiss NS, Beresford SA, Heckbert SR, Wong C, Stehman-Breen C. Increased risk of hip fracture among patients with end-stage renal disease. Kidney Int. July 2000;58(1):396-399.
1997	Gullberg B, Johnell O, Kanis JA. World-wide projections for hip fracture. Osteoporos Int. September 1997;7(5):407-413.
2012	Tarride J-E, Hopkins RB, Leslie WD, Morin S, Adachi JD, Papaioannou A, Bessette L, Brown JP, Goeree R. The burden of illness of osteoporosis in Canada. Osteoporos Int. November 2012;23(11):2591-2600.
2012	Kanis JA, Odén A, McCloskey EV, Johansson H, Wahl DA, Cooper C; IOF Working Group on Epidemiology and Quality of Life. A systematic review of hip fracture incidence and probability of fracture worldwide. Osteoporos Int. September 2012;23(9):2239-2256.
1993	Cooper C, Atkinson EJ, Jacobsen SJ, O’Fallon WM, Melton LJ III. Population-based study of survival after osteoporotic fractures. Am J Epidemiol. May 1, 1993;137(9):1001-1005.
2006	Johnell O, Kanis JA. An estimate of the worldwide prevalence and disability associated with osteoporotic fractures. Osteoporos Int. December 2006;17(12):1726-1733.
1992	Cooper C, Campion G, Melton LJ III. Hip fractures in the elderly: a world-wide projection. Osteoporos Int. November 1992;2(6):285-289.