Low ALT Is Associated with IBD and Disease Activity: Results from a Nationwide Study

Background: Sarcopenia is underdiagnosed in patients with inflammatory bowel disease (IBD). Low alanine transaminase (ALT) is associated with sarcopenia. We evaluated the association between low ALT and the presence of IBD and disease activity. Methods: Data were collected from a national Israeli health insurer cohort comprising 976,615 patients. Patients with a diagnosis of IBD were compared to healthy controls. After exclusion of patients with liver disease, ALT > 40 IU/L and age < 18, a total of 233,451 patients were included in the analysis. Low ALT was defined as <10 IU/L. Results: Low ALT was more common amongst patients with IBD than in healthy controls (7.76% vs. 5.7% p < 0.001). Low ALT was found in 148 (7.9%) of the patients with CD and 69 (6.9%) of the patients with UC. For CD, low ALT was associated with increased fecal calprotectin (FC) and CRP (223.00 μg/mg [63.45-631.50] vs. 98.50 [31.98-324.00], p < 0.001, 9.10 mg/L [3.22-19.32] vs. 3.20 [1.30-8.30], p < 0.001) and decreased albumin and hemoglobin (3.90 g/dL [3.60-4.20] vs. 4.30 [4.00-4.50], p < 0.001,12.20 g/dL [11.47-13.00] vs. 13.60 [12.60-14.70], p < 0.001). For UC, low ALT was associated with higher FC and CRP (226.50 μg/mg [143.00-537.00] vs. 107.00 [40.85-499.50], p = 0.057, 4.50 mg/L [1.90-11.62] vs. 2.30 [1.00-6.20], p < 0.001) and with lower albumin and hemoglobin (4.00 g/dL [3.62-4.18] vs. 4.30 [4.10-4.40], p < 0.001, 12.40 g/dL [11.60-13.20] vs. 13.60 [12.60-14.60], p < 0.001). These findings remained consistent following multivariate regression and in a propensity score-matched cohort. Conclusions: Low ALT is more common in patients with IBD and is associated with biochemical disease activity indices.