Age adjusted D-dimer in the Belfast Health and Social Care Trust: A retrospective study

D-dimers combined with clinical pre-test probability (PTP) scores are used to determine the likelihood of a venous thromboembolic event (VTE). It is recognised that with advancing age, d-dimer values increase, leading to a cohort of patients with a d-dimer above the standard cut-off of 500μg/L. A recent systemic review, examined the accuracy of an age-adjusted D-dimer in those aged > 50 years with a low clinical risk of a VTE. This showed an increase in specificity without loss of sensitivity. Our study, aimed to examine a population of patients, who between 2011 and 2014 underwent ultrasound Doppler studies of lower limbs. By applying a corresponding age-adjusted D-dimer, we determined the sensitivity and specificity and compared this to use of conventional D-dimer.