Age-associated Higher Disease Activity and Lower Quality of Life among Patients with Inflammatory Bowel Disease at a Tertiary Referral Center

Abstract

Purpose: Younger age at diagnosis is associated with more aggressive phenotypes in Crohn's disease (CD) and ulcerative colitis (UC). We evaluated the effect of age at initial visit on disease activity and disease-specific quality of life over time in a tertiary referral IBD cohort. Methods: Retrospective cohort study in IBD patients identified from an IRB-approved clinical data repository from July, 2004 to July, 2012. We compared age at index visit (<40 years, 40-59 years and age ≥ 60 years) with disease activity as measured by the Harvey Bradshaw Index (HBI) for CD, and the Simple Clinical Colitis Activity Index (SCCAI) for UC. Disease-specific quality of life was measured by the SIBDQ (Short Inflammatory Bowel Disease Questionnaire). Repeated measures linear regression was used to assess this association over time, adjusted for confounding variables. Results: 609 patients with CD and 310 patients with UC were included. 45% were male, 79% were Caucasian. Mean disease duration was 9.4±9.9 years. 16% were current smokers, 27% were former smokers, and 57% were never smokers. After adjustment for sex, smoking status and disease duration, at index visit, CD patients age 40-59 had higher mean HBI scores (5.7 ± 0.5) and lower mean SIBDQ scores (42.6 ± 1.2), compared to patients over age 60 (HBI 3.8 ± 0.5, SIBDQ 48.0 ± 1.6) (p<0.001). Over time, all CD patients demonstrated improvement in HBI and SIBDQ scores. However, HBI score improvement was less pronounced in the youngest patients (p<0.001), while improvement in SIBDQ scores did not differ between age groups (p=0.38). Patients with UC under age 40 at the index visit had lower SCCAI scores (3.2 ± 0.3) compared to older patients 40-59 (4.0 ± 0.4, p <0.001) (Figure 2), and higher SIBDQ scores (51.0 + 1.5) compared to patients age 40-59 (SIBDQ 47.1 ± 1.8, p<0.0001). All patients with UC demonstrated improvement in SCCAI and SIBDQ scores, with no difference in the rate of improvement in these scores among age groups (SCCAI slope p=0.32, SIBDQ slope p=0.17). Conclusion: IBD patients aged 40-59 years at initial visit had increased baseline disease activity and decreased quality of life compared to younger and older patients. Patients experienced decreased disease activity and improved quality of life over time, although CD patients under age 40 did not improve as greatly as older patients. Our results suggest that patient age at initial evaluation can be a marker of more severe disease and should be noted when considering early aggressive therapy.