Common bile duct stones (CBDS) are a prevalent digestive disorder with a high incidence. It is a chronic recurrent hepatobiliary disease that develops due to impaired metabolism of cholesterol, bilirubin, and bile acid (1). The incidence of cholelithiasis is 5–15%, among which the incidence of CBDS is approximately 5–30% (2). It is known that CBDS incidence increases with age, particularly in the elderly population (3). CBDS occur when a gallstone blocks the common bile duct (CBD), thereby blocking the passage of the bile, which flows back into the liver (4). This can lead to symptoms such as right-sided abdominal pain, jaundice, nausea, vomiting, and fever. If the stone is deposited in the CBD and blocks it, acute obstructive suppurative cholangitis can occur, which causes symptoms such as septic shock and altered consciousness and is a life-threatening condition, particularly in elderly patients (5).

Presently, the optimal treatment for CBDS remains controversial. The most widely accepted techniques are endoscopic retrograde cholangiopancreatography (ERCP) plus laparoscopic cholecystectomy (LC) and laparoscopic common bile duct exploration (LCBDE) (3). According to previous studies, LCBDE and ERCP have similar postoperative complication and mortality rates in the general population; however, LCBDE has certain advantages over ERCP with regard to the stone clearance rate, overall success rate, and length of hospital stay, which make the former more cost-effective (6–9). Following advances in medical technology, the success rate of treating CBDS has greatly increased. However, even after the complete removal of stones, CBDS recurrence is a common phenomenon, ranging from approximately 4–25%, with the recurrence rate increasing over time (10–13). According to literature reports, the risk factors for CBDS recurrence mainly include age, lipid metabolism, nutrition, obesity, biliary infection, bile stasis, biliary inflammation, periampullary diverticulum, the number and size of stones, CBD diameter, and history of previous cholecystectomy or ERCP (2, 14, 15). These risk factors, however, remain debatable, and the extent to which each factor influences CBDS recurrence and their interplay remain unclear. Consequently, based on these research findings, clinicians are unable to assess the likelihood of postoperative CBDS recurrence in patients, thus making it difficult to implement early prevention strategies for high-risk populations.

In this context, we analyzed the clinical data of patients to identify the most appropriate predictive factors and subsequently constructed a prediction model for CBDS recurrence after choledocholithotomy in elderly patients.

CBDS is a common disease for elderly patients (18). The natural history of CBDS is less well known than that of gall bladder stones. Complications of CBDS include pain, partial or complete biliary obstruction leading to obstructive jaundice, cholangitis, hepatic abscesses, pancreatitis, and secondary biliary cirrhosis, which are potentially life-threatening (19). Patients diagnosed to have CBDS should be recommended to undergo extraction of stones whenever possible, as it provides significant benefits, particularly for symptomatic patients (19–21).

CBDS recurrence poses a significant challenge for physicians. In our study, approximately 8.8% of patients had CBDS recurrence after stone removal procedures and surgeries; this rate was similar to that reported in previous studies (13, 22). A history of cholecystectomy, WBC count ≥11.0 × 10⁹/L, preoperative TBIL level ≥ 36.5 mmol/L, number of stones ≥2, maximum stone diameter ≥ 0.85 cm, and T-tube drainage were independent risk factors affecting CBDS recurrence in elderly patients after choledocholithotomy. A history of cholecystectomy and the placement of a T-tube drainage catheter are independent risk factors as compared to other factors and have been rarely reported as significant factors of CBDS recurrence in previous studies (2, 13, 23).

It remains controversial whether a history of cholecystectomy is associated with CBDS recurrence. Because some CBDS are formed due to the migration of gallbladder stones, also known as secondary CBDS, it is generally believed that cholecystectomy can prevent CBDS recurrence to some extent (24). However, Heo et al. (25) argued that cholecystectomy was not correlated with a reduction in CBDS recurrence. Furthermore, a case–control study showed no significant difference in the cumulative CBDS recurrence rate between the cholecystectomy group and the non-cholecystectomy group (16). In contrast, other researchers believed that a history of cholecystectomy was closely associated with CBDS recurrence (13). In our present study, patients with a history of cholecystectomy had a significantly higher rate of CBDS recurrence than those without cholecystectomy (17.78% vs. 7.47%, p < 0.001). Furthermore, the multivariate Cox analysis revealed that a history of cholecystectomy was an independent risk factor for CBDS recurrence after choledocholithotomy in elderly patients. This may be related to post-cholecystectomy dysfunction of the Oddi sphincter. After cholecystectomy, the damage to the nerves surrounding the gallbladder neck and the abnormal secretion of cholecystokinin can lead to a spasm of the Oddi sphincter, ultimately resulting in biliary stasis and CBDS recurrence (26–29). Intraoperative manipulation and postoperative adhesions can also potentially cause inadvertent bending or narrowing of the CBD, which is also a risk factor for promoting the formation of CBDS (30).

The placement of a T-tube drainage catheter in the biliary tract is also a debatable topic. Our multivariate analysis revealed that CBDS recurrence was 2.7-fold higher in patients with T-tube insertion than in those with no T-tube insertion (HR = 2.718, 95% CI: 1.230–6.010, p = 0.013). Improper placement of the T-tube can lead to the twisting or bending of the CBD, while prolonged T-tube drainage can increase the risk of bacterial infections within the bile duct, which may contribute to the high recurrence rate of CBDS. It is worth noting that when surgeons suspect the potential recurrence of CBDS after surgery, they often choose to place a T-tube, which may lead to selection bias (23).

We also developed a nomogram for predicting CBDS recurrence after choledocholithotomy. According to previous studies, a C-index of >0.7 indicates that the established nomogram has good accuracy and acceptable discriminatory power (31). The C-index of our developed nomogram was 0.758 (95% CI: 0.698–0.818), and the internal validation value based on the bootstrap method was 0.758 (95% CI: 0.641–0.875); these values demonstrated the effectiveness of the model.

The present study also has some limitations. First, the diagnosis and selection of patients were performed by clinicians; however, there still might be some unknown factors that could have influenced our model. Second, because of the retrospective nature of this single-center study, the sample size was limited, and clinical data were missing for a few patients; this introduced certain limitations and potential selection bias in the study. Third, the study conducted only internal validation of the model and currently lacks external data to further evaluate the predictive ability of the model.

In conclusion, because of the delayed recurrence of CBDS, it is recommended to continue follow-up of patients after choledocholithotomy. Our results indicated that a history of cholecystectomy, WBC count ≥11.0 × 10⁹/L, preoperative TBIL level ≥ 36.5 mmol/L, number of stones ≥2, maximum stone diameter ≥ 0.85 cm, and T-tube drainage were risk factors of CBDS recurrence after choledocholithotomy in elderly patients. We also developed a prediction model for CBDS recurrence with high efficiency and accuracy. We anticipate that our present research will contribute to improve the prognosis of patients with CBDS.

The original contributions presented in the study are included in the article/supplementary material, further inquiries can be directed to the corresponding author.

Ethical review and approval was not required for the study on human participants in accordance with the local legislation and institutional requirements. Written informed consent from the participants was not required to participate in this study in accordance with the national legislation and the institutional requirements.

HW and Z-jL conception and design and drafting and revision of the manuscript. Y-qH and PT was responsible for tables and figures. S-yD, WZ, and S-yY helped with the literature gathering. All authors critically appraised the final manuscript, gave final approval of the version to be published, and agreed to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.