P641 Vitamin D levels during remission are associated with the risk of clinical relapse in patients with ulcerative colitis
J. M. Gubatan*, S. Mitsuhashi, T. Zenlea, L. Rosenberg, S. Robson, A. Moss
Beth Israel Deaconess Medical Centre, Harvard Medical School, Division of Gastroenterology, Department of Medicine, Boston, Massachusetts, United States
Serum Vitamin D levels have been associated with disease activity in ulcerative colitis, but whether they influence the risk of disease relapse is unknown. We sought to determine the association between baseline vitamin D levels and subsequent risk of relapse in patients with ulcerative colitis in clinical remission.
Patients with a diagnosis of ulcerative colitis (UC) who were in clinical remission were prospectively enrolled in an observational cohort after a surveillance colonoscopy. Clinical relapse (defined by having a UC-related hospitalisation, medication escalation, colectomy, or designated by physician’s assessment) was determined over 12 months. Baseline 25-hydroxy-Vitamin D levels were measured via Enzyme-linked Immunosorbent Assay.
In total, 170 subjects were enrolled, and of these 70 were randomly selected for measurement of baseline vitamin D levels; 20 later relapsed, and 50 did not relapse over 12 months. Mean baseline vitamin D level was higher amongst subsequent non-relapsers vs relapsers; 29.5 ng/mL vs 50.3 ng/mL (p = 0.001). An ROC curve of vitamin D levels for the outcome of relapse had an area under the curve (AUC) of 0.7. Patients with a vitamin D level ≥ 35 ng/mL had a decreased risk (OR 0.7, p = 0.0012) of clinical relapse in univariate analysis. A vitamin D level of ≥ 35 ng/mL was also associated with a lower risk of endoscopic inflammation (OR 0.8, p = 0.02) and histological inflammation (OR 0.7, p = 0.004).
In patients with UC in clinical remission, serum vitamin D levels ≥ 35 ng/mL were associated with a significantly lower risk of subsequent clinical relapse over 12 months. Clinical trials of vitamin D therapy to obtain vitamin D levels above this threshold should be considered.