Risk of Lower and Upper Gastrointestinal Bleeding, Transfusions, and Hospitalizations with Complex Antithrombotic Therapy in Elderly Patients.
Abraham NS, Hartman C, Richardson P, Castillo D, Street RL Jr, Naik AD. Circulation. 2013 Sep 11. [Epub ahead of print]
Complex antithrombotic therapy (CAT) prescribed to elderly patients increases the risk of gastrointestinal bleeding. We quantified upper (UGIE) and lower GI (LGIE) events, transfusions and hospitalizations in a national cohort of elderly veterans prescribed CAT.
METHODS AND RESULTS:
Veterans ≥ 60 years prescribed anticoagulant-antiplatelet (i.e., ACAP); ASA-antiplatelet (i.e., ASAP); ASA-anticoagulant (i.e., ASAC) or triple therapy (i.e., TRIP; anticoagulant-antiplatelet-ASA) were identified from the national pharmacy database (10/01/02-09/30/08). Prescription-fill data were linked to VA and Medicare encounter files, each person-day of follow-up assessed for CAT exposure, and outcomes defined using diagnostic code algorithms derived following chart abstraction. Incidence density ratios (compared to the reference category of no CAT) and survival analysis was conducted. Among 78,133 veterans (98.6% white; mean age, 72.3 [SD 7.7]), 64% were prescribed ASAP and ACAP and 6% TRIP. Incidence of UGIE was 20.1/1000 patient-years (PY) and LGIE was 70.1/1000 PY. ASAC and TRIP were associated with highest incidence of transfusion and hospitalization. A 40% to 60% increased risk of UGIE was observed with all strategies. LGIE was 30% higher with ACAP, and transfusion increased with ASAC (HR 6.1; 95% CI: 5.2-7.1) and TRIP (HR 5.0; 95% CI: 4.2-5.8). Increased risk of hospitalization was noted with all strategies. The number needed to harm (NNH) for UGIE or LGIE ranged from 52 to 65 and 15 to 23, respectively. The NNH for hospitalization was 39 (ACAP), 34 (ASAC), 67 (ASAP) and 45 (TRIP) patients.