Adherence to postoperative thromboprophylactic medication among gynecologic oncology patients: A subanalysis

Venous thromboembolism (VTE) is a major cause of morbidity and mortality among gynecologic cancer patients, especially in the immediate postoperative period. We sought to identify patterns related with patient non-adherence to postoperative prophylactic anticoagulation.

Participant data (N = 400) were reviewed from a previously conducted randomized controlled trial comparing the safety and efficacy of prophylactic postoperative anticoagulation with enoxaparin versus apixaban among gynecologic oncology patients. Variables hypothesized to be related to medication adherence were pre-selected by the study authors, and adherence was defined as missing ≤2 days of medication (4 pills or 2 injections) in 28 days postoperatively. For univariate comparisons and multivariate modeling, the threshold for statistical significance was set at p < .05.

Non-adherence (N = 64) was associated with lower quality of life (QOL) score, history of anxiety disorder, decreased medication satisfaction, taking more medications at baseline, higher baseline heart rate, fewer total intraoperative procedures, not undergoing radical hysterectomy and/or lymph node dissection, not meeting 2-week postoperative milestones, and 28-day emergency department (ED) visit or readmission. African American race, lower mental QOL, difficulty remembering to take medication, and 28-day ED visit or readmission were predictive of non-adherence in a multivariate model. Patients taking enoxaparin versus apixaban more frequently attributed non-adherence to pain or bruising (25.0% vs. 3.1%, P = .01).

Our findings provide new insights into factors associated with medication adherence that are particularly relevant to gynecologic oncology patients after surgery. Preoperative interventions to identify patients with these risk factors for more intensive followup of postoperative anticoagulation regimen may help increase medication adherence.