Demographics, Comorbidities, and Biometric Characteristics of Infliximab-treated Patients with Crohnʼs Disease or Ulcerative Colitis in the Ambulatory Care Setting

Abstract

Recent data reported rheumatoid arthritis patients with higher BMI, particularly those > 30, had lower responses to infliximab (IFX) than those with lower body mass index (BMI).1 Likewise, immunomodulation with azathioprine in Crohn's disease (CD) and ulcerative colitis (UC) has been shown to be influenced by BMI.2 These data suggest BMI may influence response to medical therapy. Published clinical trial data describe the demographic and weight characteristics of patients with CD or UC treated with IFX. However, biometric data (weight and BMI) among individuals with CD or UC, treated within United States (U.S.) clinical practices, are lacking. To describe the real world demographic, comorbidity, and biometric data of IFX-treated patients with CD or UC in the clinical practice setting. A retrospective analysis was conducted using electronic medical records from the GE Healthcare Centricity™ Clinical Data Services (CDS) database. The CDS includes de-identified patient-level clinical data for patients treated in U.S. ambulatory care settings. Demographic, comorbidity, weight, and BMI data were evaluated for patients (≥18 years old) with ≥ 1 claim for infliximab and an ICD-9 diagnosis code for CD (555.x) or UC (556.x). Patient records containing both CD and UC diagnoses, in the medical history prior to IFX, were categorized as a combined CD/UC group. Out of 13,111 inflammatory bowel disease (IBD) patients, a total of 899 IFX-treated patients were identified: 593 with CD-only, 227 with UC-only, and 79 with both CD/UC. More than half of all patients were female (CD-only=60%, UC-only=55%, and CD/UC=66%). Approximately 50% of records reported the patient's race, and of those reported: 90% were Caucasian, 8% Black, and <1% were Asian, American Indian, and Hispanic. The top three comorbidities among IFX-treated CD-only and UC-only patients were hypertension (24% and 21%), depressive disorders (23% and 18%), and gastroesophageal reflux disease (17% and 15%), respectively. Among all patients with a documented body weight at the time of first IFX dose (n=759), 48% had a mean body weight ≥ 80 kg. Mean (SD) body weights at the time of first IFX dose were 81 (22) kg, 82 (21) kg, and 80 (21) kg for CD-only, UC-only, and CD/UC patients, respectively. The calculated mean (SD) BMI at time of diagnosis was 28 (6), 27 (6), and 28 (7) for CD, UC, and CD/UC patients, respectively. These real world data support the demographic characteristics of CD and UC patients previously reported in clinical trials. However, the biometric data suggest that CD and UC patients have slightly higher mean weights compared to that found in IFX clinical trials (68-74 kg3 and 77-80 kg4), and mean BMI values that are classified as overweight (≥25) using World Health Organization definitions. Additional research is needed to examine the relationship between BMI and clinical outcomes of individuals with CD and UC.