Changes in thrombelastograph variables associated with aging.

Aging is associated with hypercoagulability. To assess thrombelastography (TEG) variables associated with aging, 132 adult patients of various ages undergoing orthopedic surgery for fracture repair had venous blood samples withdrawn for testing of recalcified TEG before the induction of anesthesia. Age was weakly correlated with all TEG variables: r time (R) (r = -0.45, P < 0.001; R = 19.5 - 0.09 x age), k time (K) (r = -0.49, P < 0.001; K = 6.5 - 0.04 x age), maximum amplitude (MA) (r = 0.25, P < 0.01; MA = 53.3 + 0.07 x age), and alpha (r = 0.52, P < 0.001; alpha = 52.8 + 0.2 x age). The correlation was stronger for men than for women. Only R was significantly correlated with age when the women were separately analyzed. Part of the correlation may be attributable to a concurrent decrease in hemoglobin with aging, but age remained an independent predictor of R, K, and alpha on forward stepwise linear multiple regression analysis. Aging was weakly associated with changes in TEG variables, which should be allowed for when interpreting TEG measurements in the elderly.