Predicting intracranial lesions by antiplatelet agents in subjects with mild head injury.

BACKGROUND

The effect of pre-injury antiplatelet treatment in the risk of intracranial lesions in subjects after mild head injury (Glasgow Coma Scale (GCS) 14-15) is uncertain.

METHODS

The potential risk was determined, considering its increasing use in guidelines on cardiovascular disease prevention, and ageing of the trauma population in Europe.

PATIENTS: The interaction of antiplatelet therapy with the prediction variables of main decision aids was analysed in 14,288 consecutive adolescent and adult subjects with mild head injury.

MEASUREMENTS: Any intracranial lesion at CT scan was selected as an outcome measure in a multivariable logistic regression analysis.

RESULTS

Intracranial lesions were demonstrated in 880 cases (6.2%), with an unfavourable outcome at 6 months in 86 (0.6%). Antiplatelet drugs were recorded in 10% of the entire cohort (24.7% in the group over 65 years). They increased the risk of intracranial lesions in the univariate analysis (OR 2.6; 95% CI 2.2 to 3.1), interacting with age in the multivariate analysis (antiplatelet OR 2.7 (1.9 to 3.7); age ≥75 years 1.4 (1.0 to 1.9)). The inclusion of these two variables with those included in previous decision aids for CT scanning (GCS, neurodeficit, post-traumatic seizures, suspected skull fracture, vomiting, loss of consciousness, coagulopathy) predicted intracranial lesions with a sensitivity of 99.7% (95% CI 98.9 to 99.8) and a specificity of 54.0% (95% CI 53.1 to 54.8), with a CT ordering rate of 49.3% (undetermined events 0.2:1000).

INTERPRETATION: Antiplatelet drugs need to be considered in future prediction models on mild head injury, considering their increasing use and progressive ageing of the trauma population.