The impact of combined use of fall-risk medications and antithrombotics on injury severity and intracranial hemorrhage among older trauma patients.

Purpose: Use of fall-risk medications (medications that increase risk of falling in the elderly as defined by Beers criteria, STOPP/START criteria, and other literature) or antithrombotics is common in the elderly, and the impact of their concomitant use should be assessed in regards to fall injuries. The primary objective of this study is to assess the simultaneous outpatient use of fall-risk medications and antithrombotics in elderly fall-patients, and secondarily to analyze the injury severity score and occurrence of intracranial hemorrhage.

Methods: Consecutive chart review at a level 2 trauma center in California, USA from August 01, 2009 to October 31, 2010. Records included 112 patients at least 65 years of age admitted with an outpatient fall. Fisher's exact and Student's t-tests were used (alpha 0.05, two-tailed) to examine prescribing patterns, intracranial hemorrhage occurrence, and injury severity score. Regression adjusted for antithrombotic and fall-risk medication type and number, opiate use, co-morbidities, age, and gender.

Results: Thirty-nine percent (44/112) of outpatients were prescribed antithrombotics plus fall-risk medications. The mean injury severity score (ISS) was 13.3 (range 1-26, standard deviation 7.2) for patients taking both medication classes versus 9.7 (range 1-25, standard deviation 7.5) for patients taking antithrombotics alone (p = 0.027). Additionally, in patients over 80 years of age, intracranial hemorrhage occurred more frequently with the use of antithrombotics plus fall-risk medications versus antithrombotics alone (18/29 = 62.1% versus 7/24 = 29.2%, p = 0.027, odds ratio = 3.974, 95% confidence interval = 1.094-15.010). Multivariate analyses showed an independent relationship between intracranial hemorrhage occurrence and type of therapy, as well as injury severity score and simultaneous therapy with fall-risk medications and antithrombotics.

Conclusion: Simultaneous prescribing of antithrombotics and fall-risk medications is common. For outpatients over 80 years of age, the odds of experiencing a post-fall intracranial hemorrhage are 4 times higher when prescribed antithrombotics plus fall-risk medications compared to antithrombotics alone, and injury severity is higher with combined use of these medication classes.