Elevated serum globulin fraction as a biomarker of multiyear disease severity in inflammatory bowel disease

Serum protein reflects albumin and globulin levels, both of which can be altered in inflammatory bowel disease (IBD). The implications of a high globulin fraction in IBD are unknown. We hypothesized that a high globulin fraction may function independently of albumin as a biomarker of disease severity in IBD patients over a multiyear period.

This was an observational study from a prospective IBD registry of a tertiary care center. High globulin fraction was defined as an elevated globulin level >4 g/dL. Data collected included patient demographics, medication exposures, quality-of-life scores, disease activity, emergency department visits, telephone calls, hospitalizations, and IBD-related surgeries over a 4-year period. Comparisons between patients with a high globulin fraction and those without were performed using Pearson's chi-squared, Student's and Mann-Whitney tests. Multivariate analyses were used to assess the relationship between high globulin fraction and healthcare utilization.

A total of 1767 IBD patients with a 4-year follow up were included: 53.5% female, mean age 48.4±15.1 years, and 65.4% with Crohn's disease. Of these patients, 446 (25.2%) presented with elevated globulin fraction. Patients with a high globulin fraction were more likely to be hospitalized during the study period. This result remained significant after multivariate analysis for both Crohn's disease patients and those with ulcerative colitis.

A high globulin fraction is independently associated with greater disease severity and healthcare utilization in IBD patients, and may function as a routinely available biomarker of a more severe future disease trajectory.