Association between platelet count and mucosal healing in Japanese patients with ulcerative colitis: a cross-sectional study.

BACKGROUND Mucosal healing (MH) has been indicated as the therapeutic goal for ulcerative colitis (UC). Platelet count is known as an inflammation evaluation. However, the association between platelet count and MH among patients with UC is still scarce. We therefore assessed this issue among Japanese patients with UC. METHODS The study subjects consisted of 345 Japanese patients with UC. Platelet count was divided into quartiles on the basis of the distribution of all study subjects (low, moderate, high, and very high). Several endoscope specialists were responsible for evaluating MH and partial MH, which was defined as a Mayo endoscopic subscore of 0 and 0-1, respectively. Estimations of crude odds ratios (ORs) and their 95% confidence intervals (CIs) for partial MH and MH in relation to platelet count were performed using logistic regression analysis. Age, sex, CRP, steroid use, and anti-Tumor necrosis factor α (TNFα) preparation were selected a priori as potential confounding factors. RESULTS The percentage of partial MH and MH were 63.2 and 26.1%, respectively. Moderate and very high was independently inversely associated with partial MH (moderate: OR 0.40 [95%CI 0.19-0.810], very high: OR 0.37 [95%CI 0.17-0.77], p for trend = 0.034). Similarly, moderate, high, and very high were independently inversely associated with MH (moderate: OR 0.37 [95% CI 0.18-0.73], high: OR 0.41 [95% CI 0.19-0.83], and very high: OR 0.45 [95% CI 0.21-0.94], p for trend = 0.033) after adjustment for confounding factors. CONCLUSIONS Among patients with UC, platelet count was independently inversely associated with MH.