Liver and Bile
Eur J Gastroenterol Hepatol. 2024;36(5):628–35
A new and simple score to predict adequate and deep response to ursodeoxycholic acid in patients with primary biliary cholangitis: The ALP-A score
Background: Ursodeoxycholic acid (UDCA) is the standard treatment for primary biliary cholangitis (PBC), but a significant proportion of patients do not respond adequately, leading to increased risk of adverse outcomes. This study aims to develop a new and straightforward predictive score to identify PBC patients likely to achieve a complete response to UDCA.
Methods: A logistic regression analysis was conducted using a derivation cohort of PBC patients to identify pretreatment variables associated with response to UDCA. This analysis led to the development of the ALP-A score, calculated as: age at diagnosis divided by (alkaline phosphatase [ALP] at diagnosis/upper limit of normal). ALP-A score accuracy was evaluated using the area under the receiver-operating characteristic curve, validated with a large external cohort from Brazil. Additionally, the correlation between the ALP-A score and the previously validated UDCA response score (URS) was assessed.
Results: The ALP-A score had good predictive power for adequate (area under the curve [AUC], 0.794; 95% confidence interval [CI]: 0.737–0.852) and deep (AUC, 0.76; 95% CI: 0.69–0.83) UDCA response at 1 year of treatment. A cut-off score of 17 and 23 points was determined to be the optimal threshold for distinguishing adequate and deep responders, respectively, from non-responders. ALP-A score demonstrated a sensitivity of 73%, specificity of 71%, positive predictive value of 65%, negative predictive value of 78%, and overall accuracy of 72% for biochemical response. The URS displayed similar discriminative ability (AUC, 0.798; 95% CI: 0.741–0.855).
Conclusion: The ALP-A score performs comparably to the ursodeoxycholic acid (UDCA) response score but offers the great advantage of simplicity for routine clinical use. It serves as a valuable tool to identify primary biliary cholangitis patients less likely to respond to UDCA treatment, facilitating early consideration of alternative therapeutic approaches