Diseases of the pancreaticobiliary tract are common among elderly individuals, with common bile duct stones and malignancies accounting for over 70% of jaundice cases in patients older than 75 years [21]. In this age group, biliary tract disease is the leading cause of abdominal surgery, which carries a high risk of complications and mortality [12]. Endoscopic retrograde cholangiopancreatography (ERCP) reduces the need for urgent surgery and lowers morbidity in these patients [22]. With the increasing elderly population, the number of ERCP procedures has risen globally, but older patients are considered at higher risk for ERCP-related complications because of multiple comorbidities. [13]

Large common bile duct (CBD) stones (≥ 1.5 cm) and multiple stones present challenges for endoscopic removal, decreasing the success rate of traditional methods like endoscopic sphincterotomy (EST) combined with basket or balloon techniques [10]. Other techniques such as mechanical lithotripsy or EST combined with endoscopic papillary large balloon dilation (EPLBD) can improve success rates, though they increase the procedure's complexity and duration, and raise the risk of complications, especially in elderly patients with comorbid conditions [11]. For difficult-to-remove stones, current guidelines recommend temporary stent placement for bile duct drainage to prevent complications like stone impaction and cholangitis [7, 10]. Elective endoscopic stone removal following short-term stenting is a commonly adopted strategy.

Previous studies have demonstrated that combining EST with EPLBD is a safe and effective approach for removing large CBD stones in elderly patients [14, 15]. However, there is limited research on whether immediate endoscopic stone removal or a strategy involving short-term bile duct stent placement followed by elective stone removal is safer and more effective for this population, especially those with chronic diseases and poor overall health.

Our study evaluated the efficacy and safety of temporary bile duct stenting followed by elective stone removal compared to immediate stone removal in high-risk elderly patients with large or multiple CBD stones. Results showed a higher stone clearance rate and a lower incidence of ERCP-related adverse events in the stent drainage group compared to the immediate removal group.

For treatment of choledocholithiasis, EST with balloon or basket extraction remains the standard, with a clearance rate of 80–92.3%. [23–26]. For large or multiple stones, elective removal after short-term stent placement shows a more than 90% clearance rate. [6, 27, 28]

Han J. and colleagues reported that endoscopic stone removal was successful in 92.8% of patients (26 out of 28) following plastic stenting and the use of ursodeoxycholic acid [29]. However, the European Society of Gastrointestinal Endoscopy (ESGE) advises against using ursodeoxycholic acid or other choleretic agents for the treatment of common bile duct stones (CBDSs) or for preventing their recurrence after endoscopic clearance [7]. Meng K. and his team found that the stone clearance rate in the group undergoing elective stone removal was higher than in the immediate stone removal group (89.5% vs. 75.3%, P = 0.049) [11]. Our study showed similar results, with success rates of 80% in the immediate removal group and 94% in the group receiving stent drainage followed by elective stone removal. We believe this difference is due to the reduction in size and hardness of the CBD stones after short-term stent placement.

Our study demonstrated that after short-term stenting, the average size of CBD stones decreased significantly from 1.42 to 0.98 cm. Meng K. et al. observed a similar reduction, with the main CBD stone diameter decreasing from 1.95 to 1.59 cm. They also noted that in one patient, no stones were detected during the second ERCP, suggesting the possibility of spontaneous stone removal due to fragmentation from stent placement [11]. Similar findings have been reported in previous studies [9, 27, 30]. While short-term biliary stent placement can reduce the size and number of CBD stones, the precise mechanism remains unclear. It is hypothesized that the friction between the stent and the stones caused by breathing and intestinal movements may lead to stone fragmentation. Additionally, changes in bile composition due to the reflux of duodenal contents (intestinal fluid or gas) following stent placement could also play a role. [6, 29]

In our cohort, post-stenting downsizing was observed in 79% of patients in Group A. However, in cases where stone removal remained difficult, most stones showed minimal or no size reduction, and nearly all involved a single large stone > 1.6 cm. These findings suggest that initial stone size may serve as a useful predictor of response to stenting and could assist in selecting patients most likely to benefit from a stent-first strategy. Although stone hardness and composition were not quantitatively evaluated in this study, they are likely to influence outcomes. Future research should incorporate radiologic parameters, such as CT attenuation values, to better assess stone density and composition. Developing predictive models that integrate stone size, number, and radiologic density may enhance individualized decision-making in the endoscopic management of complex CBD stones.

In our study, we used plastic stents for all patients undergoing biliary stenting. Meng et al. used double pigtail stents in their study and reported similar results to ours in terms of stone size reduction and stone clearance rates [11]. However, there is limited data available on the most suitable types of biliary plastic stents for short-term placement and the optimal duration for which they should remain in place. Additionally, there is little information on whether placing one or more biliary stents is more advantageous.

The only available retrospective study on this matter included 64 elderly patients (aged 65 and older) with large (≥ 20 mm) or multiple (≥ 3) common bile duct (CBD) stones. These patients received either a single or double plastic stent during the initial ERCP. Approximately three months later, a second ERCP was conducted to attempt stone removal using standard techniques. This study found that double plastic biliary stenting (7 or 8.5 Fr) was more effective than single stenting (8.5 Fr) in maintaining stent patency over three months. However, both approaches were equally effective in reducing the size and number of stones, with no significant differences in complication rates between the two groups. [9]

The overall incidence of ERCP-related adverse events was higher in Group B compared to Group A. Specifically, the incidence of cholangitis was 7.5% in Group B, significantly higher than the 2.5% observed in Group A. This difference might be due to the more frequent use of balloon/basket or mechanical lithotripsy for stone extraction in Group B, which increases the volume of contrast dye used and prolongs the procedure time, thereby raising the risk of biliary infection. Additionally, pneumonia was more common in Group B, occurring in 6.5% of patients compared to 2% in Group A. The higher rate of pneumonia in Group B could be attributed to the longer procedure times, which increased the risk of aspiration during recovery, leading to higher rates of pneumonia and sepsis, and a higher mortality rate (3% vs. 0%).

Our subgroup analysis suggests that the stent-first approach may be more appropriate for patients with significant comorbidities (CCI ≥ 5) or those aged over 75 years. These high-risk patients exhibited higher rates of complications when managed with the stone retrieval-first approach. Although the stent-first strategy entails higher initial costs due to the requirement for two ERCP sessions, it appears to offer superior safety outcomes in frail or vulnerable populations. These findings underscore the need to individualize ERCP strategies based on patient risk profiles, prioritizing safety over cost in those at increased risk of adverse events.

Previous studies have shown that elderly patients are at a higher risk of cardiovascular events following ERCP, and a procedure time exceeding 30 min significantly elevates the risk of myocardial injury in this population [31]. However, in our study, although the ERCP procedure duration was over 30 min for Group B and during the second ERCP for Group A, the only cardiovascular event reported was atrial fibrillation. There was no significant difference in the incidence of atrial fibrillation between the two groups. When comparing the incidence of adverse events between the two ERCP procedures in Group A, there was no significant difference in the rate of ERCP-related complications, even though the procedure time was longer during the second ERCP.

Based on these findings, it seems reasonable to conclude that stent drainage followed by elective stone removal is a safe approach and does not increase the overall incidence of ERCP-related adverse events, even if two ERCP procedures are required for each patient.

This study has several limitations. First, being a single-center study, the results may not be generalizable to other clinical settings. Second, the study did not investigate which type or number of biliary plastic stents is most effective for short-term placement. Third, the optimal interval between stent insertion and elective ERCP was not determined. Fourth, stone hardness was not assessed in this study, although it may aid in predicting which stones are more likely to significantly reduce in size following stenting. Lastly, although our inclusion criteria primarily focused on the size and number of stones, we acknowledge that anatomical variations, particularly in the configuration of the distal bile duct, may also influence procedural complexity. While these parameters were not systematically evaluated in the present study, they warrant consideration in future research aimed at refining endoscopic risk stratification.

Nevertheless, to our knowledge, this is the first prospective study with a large patient cohort to evaluate the efficacy of two different approaches for retrieving large or multiple CBD stones in elderly patients. Additionally, it offers a comparison of the financial costs associated with each treatment strategy.

In conclusion, our study demonstrates that in high-risk elderly patients with large or multiple CBD stones, short-term biliary plastic stent placement followed by elective endoscopic stone removal effectively reduces stone size and simplifies the extraction process. This approach significantly improves the rate of complete stone clearance and reduces ERCP-related complications, making it particularly beneficial for elderly patients with chronic illnesses and compromised overall health.