C-reactive protein/albumin ratio as a potential inflammatory marker for predicting clinical outcomes in patients with moderate to severe ulcerative colitis: A retrospective study

Ulcerative colitis (UC) is a chronic inflammatory bowel disease that may range from mild to severe; therefore, management and prognosis remain quite challenging. Traditional assessment methods include endoscopy, which is invasive and expensive. This current study investigates the C-reactive protein/albumin ratio and other inflammatory biomarkers as potential noninvasive biomarkers for the prediction of clinical outcomes in ulcerative colitis patients. We conducted a retrospective study of 106 patients with moderate to severe UC between April 2017 and August 2023. We analyzed CAR alongside other inflammatory ratios, including platelet/lymphocyte ratio and neutrophil/lymphocyte ratio, to assess their association with clinical outcomes and predictive performance including anti-TNF therapy need, colectomy, and hospital length of stay. Several inflammatory markers were significantly associated with clinical outcomes. A higher polymorphonuclear leukocyte was associated with an increased need for anti-TNF therapy (odds ratio [OR] = 1.00, 95% confidence interval [CI]: 1.00-1.01, P = .038). Elevated C-reactive protein levels were linked to a higher likelihood of anti-TNF therapy (OR = 1.02, 95% CI: 1.00-1.03, P = .008) and colectomy (OR = 1.02, 95% CI: 1.01-1.04, P = .005). CAR also significantly predicted these outcomes, with an OR of 1.04 (95% CI: 1.01-1.08, P = .007) for anti-TNF therapy and 1.05 (95% CI: 1.01-1.09, P = .011) for colectomy. Additionally, CAR was positively associated with prolonged hospital stay (β = 0.07, 95% CI: 0.01-0.13, P = .020), as was C-reactive protein (β = 0.02, 95% CI: 0.00-0.04, P = .041) and lower hemoglobin levels (β = -0.59, 95% CI: -1.00 to -0.18, P = .005). The C-reactive protein/albumin ratio may serve as a useful complementary biomarker associated with adverse clinical outcomes in patients with moderate to severe UC, although its predictive performance was modest. Other markers, such as the erythrocyte sedimentation rate/albumin ratio, also correlated with extended hospitalization. These findings suggest CAR may serve as a complementary biomarker for monitoring disease progression and guiding treatment decisions. Further multicenter, prospective studies are needed to confirm these results.