The recently developed ACE index – which incorporates three variables at hospital admission (C-reactive protein [CRP], albumin, and endoscopic severity) – accurately predicts steroid response at hospital admission in patients with acute severe ulcerative colitis (ASUC). This is according to study findings presented at the annual Advances in Inflammatory Bowel Diseases conference by Marta Freitas, MD, of the Senhora da Oliveira Hospital in Guimarães, Portugal.*
Although intravenous steroids represent the first-line medical therapy for patients admitted to the hospital with acute UC, one study found that approximately 30% of patients with ASUC do not respond to this treatment approach and therefore require more advanced management options.
In patients with ASUC, delays in initiating therapy may be associated with an increased risk of mortality, explained Dr. Freitas and colleagues. Given this risk, there is a need for sensitive and accurate tools that can identify patients at admission who are at high risk of steroid nonresponse and who may likewise receive benefit from surgical intervention or earlier second-line therapy.
Early prediction of response to steroids in patients with ASUC at time of admission could also be helpful for prioritizing further assessment and counseling. The ACE index was recently developed to identify these patients to help improve risk stratification and facilitate earlier treatment delivery. A combination of three parameters is found within the ACE index: albumin ≤30 g/L; CRP ≥50 mg/L; and increased endoscopic severity as defined by a Mayo endoscopic score of 3.
Dr. Freitas and researchers retrospectively evaluated the performance of the ACE index in predicting steroid response in 65 patients with ASUC (mean age, 34 years). The study included a review of admissions for the disease between 2005 and 2020. The accuracy of the ACE index score was evaluated through the area under the curve.
Approximately 78.5% of patients in the retrospective cohort study had responded to steroids. Compared with nonresponders, responders had significantly different mean CRP (108.0 ± 60.0 vs. 66.0 ± 53.2 mg/dL, respectively; P = .01), mean albumin (2.9 ± 0.66 vs. 3.4 ± 0.71 g/L; P = .02), and median endoscopic severity score (3 vs. 3; interquartile range, 1 vs. 0; P = .005) at admission. In contrast, no statistically significant difference was found between responders versus nonresponders in regard to the median UC Endoscopic Index of Severity (UCEIS) score (8 vs. 7; P = .28).
Overall, the median ACE index score was 2. Steroid nonresponders had a significantly higher ACE index score (2.5 vs. 1; P = .001). The researchers noted that the ACE index score was a significant predictor of steroid response (AUC, 0.789; P = .001). Half (50.0%) of patients with an ACE index score of 3 had no response to steroids, while 86.3% of patients who had an ACE index score lower than 3 experienced a steroid response.
In a poster presentation by Hartman Brunt, MD, of the Louisiana State University Health Sciences Center in Baton Rouge, real-world data suggest there exists several inconsistencies in the use of UC-monitoring strategies recommended by clinical practice guidelines. According to a single-center retrospective chart review of adult patients with moderate to severe UC, Dr. Brunt and colleagues found that measurement of CRP decreased over time as did measurement of fecal calprotectin.
Given the lack of standardization for IBD monitoring, Dr. Hartman and colleagues noted “there is inevitably increased variability in provider care.” Consequently, this variability and lack of guideline adherence may lead to heterogeneous effects among the IBD patient population, including those that may drive suboptimal long-term outcomes.
In addition to disease monitoring, assessment of treatment response remains highly valuable, yet no clinical guidance currently exists on the use of the ACE index score in ASUC. Further research is needed to determine the validity of the ACE Index in a larger patient population to inform future clinical practice guidelines and expert consensus statements.
Ashwin Ananthakrishnan, MBBS, a gastroenterologist from Massachusetts General Hospital in Boston, said in an email to this news organization that there is an urgent need for tools that “accurately predict treatment response in severe UC because of the higher morbidity and rate of surgery in this population.” Dr. Ananthakrishnan is a co–primary investigator of the MASCC (Multi-center Acute Severe UC Cohort Study), sponsored by Johns Hopkins University, which is investigating the ACE index and other predictors of outcomes in severe UC.
“In addition, treatment decisions need to be made fairly quickly as clinical condition may change day to day,” further emphasizing the need for these predictors, added Dr. Ananthakrishnan. “At this point, the ACE index and other prediction scores have been described from observational studies, but the key is to prospectively incorporate this into a treatment algorithm.”
Dr. Ananthakrishnan explained that patients with a high ACE index, or those with UC who satisfy the high-risk criteria of other prediction models, may benefit from early or even upfront rescue therapy rather than trying steroids for 3-5 days first. He added that “the field is not quite there, and we need more study of this” approach.
Dr. Freitas, Dr. Brunt, and Dr. Ananthakrishnan declared no relevant conflicts of interest.
This article was updated 1/11/22.
*Correction, 1/11/22: An earlier version of this article misstated Dr. Martha Freitas' name.