Early post-therapy prescription drug usage among survivors of childhood cancers.

Abstract

147 Background: Childhood cancer survivors often develop treatment-associated morbidities. We hypothesized that emerging treatment-related medical morbidities would be reflected in patterns of prescription drug usage among survivors in the first three years after therapy completion. Methods: Using the Truven Health MarketScan Commercial Claims database, we identified survivors of childhood (0-21 years-old at diagnosis) leukemia, lymphoma, central nervous system (CNS), bone, or gonadal tumors who completed therapy during 2000 - 2011. Patients were identified using diagnosis codes and cancer-specific procedure codes for chemotherapy, surgery, or radiation therapy. Prescription fills during the first three years following therapy completion were examined and categorized by drug class. Median numbers of prescriptions per survivor were compared to age- and sex-matched children without cancer. Relative risks (RR) for any prescription and for prescriptions by drug class were calculated comparing survivors to children without cancer. Results: We identified 1,414 survivors and 14,140 children without cancer. The median number of unique drug class prescriptions among survivors ranged from 4 [gonadal] to 8 [CNS] in year 1 and from 2 [gonadal] to 6 [CNS] in year 3 compared to a median of 1 among children without cancer (p < 0.001 for all comparisons). Increased risks for fills of antibiotics (RR in year 1: 1.5 [CNS, gonadal], 1.7 [bone], and 1.8 [leukemia, lymphoma]) and opioids (RR in year 1: 2.4 [lymphoma], 2.7 [gonadal], 4.0 [CNS], and 4.8 [leukemia, bone]) persisted throughout the three years among all cancer groups. Survivors of leukemia, lymphoma, CNS, and bone tumors had 2-4 times the risk for antidepressant prescriptions and 4-10 times the risk for anxiolytics. Survivors of leukemia, lymphoma, and bone tumors had 8-10 times the risk for ACE inhibitor prescriptions by the third year off therapy. Conclusions: Compared to children without cancer, childhood cancer survivors have higher rates of prescription drug use across many drug classes indicative of their higher burden of medical morbidities. Careful attention should be given to emerging morbidities during the early off-therapy period.