Subcutaneous patient-controlled analgesia with hydromorphone for the treatment of refractory cancer pain in older hospitalized patients: a retrospective real-world study.

Background: Refractory cancer pain remains difficult to control in older adults, particularly when oral opioid regimens are limited by dysphagia, nausea, bowel dysfunction, or rapidly fluctuating symptom intensity. In this retrospective real-world study conducted in a dedicated geriatric oncology ward, subcutaneous patient-controlled analgesia (PCA) with hydromorphone was evaluated as a routinely implemented rescue strategy for severe opioid-refractory cancer pain. Objective: To evaluate the effectiveness and safety of subcutaneous PCA hydromorphone for refractory cancer pain in hospitalized older patients and to identify clinical factors associated with 24-h pain reduction. Methods: We reviewed consecutive admissions from January 1 to December 31, 2024. Eligible patients were aged ≥60 years, had pathologically confirmed malignancy, had refractory cancer pain defined as a pre-PCA current NRS score ≥4 recorded within 30 min before pump initiation after prior opioid exposure, and received subcutaneous hydromorphone PCA with at least one follow-up pain assessment. The primary endpoint was change in current NRS score from immediately pre-PCA to 24 h. Secondary endpoints included early analgesic response, responder rates, dosing patterns, and documented adverse events. Complete-case analyses were pre-specified; sensitivity analyses excluded implausible physiologic values and refitted the multivariable model with robust standard errors. Results: Among 499 patients (mean age 68.3 ± 6.9 years; 69% male), 82% had stage IV disease. Mean pre-PCA current NRS decreased from 4.43 ± 1.29 to 2.21 ± 0.73 at 24 h, corresponding to a mean reduction of 2.18 points (95% CI 2.05-2.31; Conclusion: In a specialized geriatric oncology ward, subcutaneous PCA hydromorphone was associated with rapid and clinically meaningful short-term pain improvement and a low rate of documented adverse events. These findings support its use as a pragmatic rescue option for carefully selected older patients with refractory cancer pain, while prospective comparative studies remain necessary before broad implementation can be recommended.