Influence of Body Mass Index on Quality of Life and Disease Activity in Crohnʼs Patients: 2010 ACG/Centocor IBD Abstract Award

Purpose: Over the past 2 decades there has been a dramatic increase in prevalence of obesity in the United States. Adipocytes are recently recognized as endocrine cells that secrete a variety of bioactive substances including tumor necrosis factor a, IL-6, and IL-8. This would suggest an increase in the inflammation burden in patients with inflammatory bowel disease and potentially result in a negative impact on health related quality of life (HRQoL). We sought to evaluate disease activity and quality of life in our Crohn's disease (CD) patient population based on body mass index. Methods: This was a retrospective study evaluating all CD pts being followed in a single referral center. Demographic information and disease characteristics were obtained from our database. Disease activity and quality of life were measured using the Harvey Bradshaw index (HBI) and Short Inflammatory Bowel Disease Questionnaire (SIBDQ) respectively. Mean body mass index (BMI) was obtained from patients who had at least 3 measurements of BMI, HBI and SIBDQ and was stratified into three categories - Normal (< 25kg/m2), Overweight (25-29.9kg/m2), and obese (> 30kg/m2). Results: There were 576 CD pts (226 men, 350 women) included with a mean age of 43 years. Approximately 33% of patients had inflammatory disease, 40% stricturing and 27% with fistulizing disease. Half the patients (50%) had involvement of both the small and large bowel. Ninety-one patients (15%) were current smokers. Fifty-six patients were non-white (10%). A majority of the patients were on combined immunomodulator and biologic therapy (57%) (27% on biologics alone and 10% on immunomodulators alone). The mean SIBDQ was 51 points with a mean HBI in our cohort of 3. Mean BMI was 26.8kg/m2 with 40%, 33%, and 27% in the normal, overweight and obese categories respectively. On multivariate analysis, the obese (-2.8, 95% CI -4.4 to -1.2) and the overweight cohorts (-1.7, 95% CI -3.2 to -0.24) had modestly reduced SIBDQ compared to those with normal weight. There was no difference in mean HBI by BMI. Obese patients had slightly lower number of surgeries on adjusted analysis (-0.4, 95% CI -7 to -0.1) but were no different in number of hospitalizations. Conclusion: Elevated BMI is associated with slight decrease in HRQoL in patients with Crohn's disease but has no impact on Crohn's disease activity represented by HBI.