Predictive Value of PHRI for Recurrence within One Year after UC Treatment: A Retrospective Study

<b>Aims/Background</b> Accurate prediction of recurrence after treatment is crucial for controlling the progression and improving the prognosis of active ulcerative colitis (UC) patients. Previous studies have evaluated the therapeutic response in UC patients by assessing mucosal healing, using measures such as the Paddington International Virtual ChromoendoScopy Score (PICaSSO) and the PICaSSO Histological Remission Index (PHRI). The PHRI is effective for evaluating treatment response and disease control in UC patients, but its predictive value for short-term recurrence has not been reported in the literature. Therefore, this retrospective analysis of clinical data aims to explore the predictive value of the PHRI and provide a reference for improving the prognosis of UC patients. <b>Methods</b> Clinical data of UC patients in clinical remission admitted to our hospital from June 2017 to June 2023 were retrospectively collected. Patients were divided into the recurrence group and the non-recurrence group, based on whether they experienced recurrence during the one-year follow-up. Clinical data, laboratory test results, and PHRI scores were collected. Variables that showed statistically significant differences between groups in univariate analysis were included in multivariate logistic regression analysis. The predictive value of PHRI was analyzed with receiver operating characteristic (ROC) curve analysis. <b>Results</b> One hundred and two UC patients in the clinical remission stage were included in this study, and there were no cases of loss to follow-up. Among them, 36 patients (35.29%) experienced recurrence within the one-year follow-up, whereas 66 patients (64.71%) did not. Compared with the non-recurrence group, the recurrence group had a more number of cases with lesions in the left-sided colon and extensive colon, higher percentages of cases that were moderate or severe, and a significantly higher colonoscopy score (<i>p</i> < 0.05). Compared with the non-recurrence group, the PHRI score of the recurrence group was significantly higher (<i>p</i> < 0.001). Multivariate logistic regression analysis showed that that the lesion range (OR = 4.127, <i>p</i> = 0.005), disease severity (OR = 3.889, <i>p</i> = 0.019), colonoscopy score (OR = 6.128, <i>p</i> < 0.001), and PHRI score (OR = 5.466, <i>p</i> < 0.001) were independent risk factors for recurrence in UC patients. The results of ROC curve analysis showed that the area under the curve of the PHRI score in predicting the recurrence of UC patients was 0.838 (95% CI: 0.760-0.916). When the optimal cut-off value was 1 point, the sensitivity and specificity were the highest, which were 89.58% and 65.58%, respectively, indicating that PHRI score had good predictive value. <b>Conclusion</b> The lesion extent, disease severity, endoscopic score, and PHRI score are associated with recurrence within one year in UC patients in the clinical remission stage, and the PHRI score has good predictive value.