Introduction:
Polypharmacy refers to the condition where an older patient is simultaneously using multiple medications, typically defined as the long-term use of five or six or more different types of drugs1, 2. The primary risks associated with polypharmacy include drug-drug interactions, decreased medication adherence, decreased cognitive function, and an increased risk of falls3. In addition, hyper-polypharmacy, a more advanced form of polypharmacy, denotes the use of ten or more different medications4. This situation is particularly concerning in older patients, where the risk of adverse drug events is further heightened4. It has been previously reported that in degenerative lumbar diseases, including lumbar spinal stenosis (LSS), there is a higher frequency of polypharmacy compared to other musculoskeletal degenerative diseases, attributed to the prevalence of comorbidities and the high number of pain relief medications5. Although it has been reported that older patients with polypharmacy represent a high-risk stratum of the perioperative population6, 7, the direct impact of polypharmacy on the postoperative outcomes of LSS remains uncertain. Thus, this study aimed to explore how polypharmacy and hyper-polypharmacy affect the postoperative outcomes of older LSS patients in terms of health-related quality of life (HRQOL) and locomotive syndrome.
Methods:
We conducted a retrospective analysis of the medical records of consecutive patients aged 65 years or older who received lumbar spinal surgery for LSS at our institution between April 2020 and March 2022. We assessed health-related quality of life (HRQOL) indicators, including ZCQ, RDQ, and JOABPEQ, preoperatively, and then at 1-year and 2-year postoperatively. Patients were classified as follows: ≥10 medications as hyper-polypharmacy (H group), 6-9 as polypharmacy (P group), and ≤5 as non- polypharmacy (N group).
Results:
A total of 148 patients were included in the study, of whom 35 were categorized into the H group, 58 into the P group, and 55 into the N group. For both ZCQ and RDQ, scores in all three groups showed significant improvement both one and two years postoperatively. However, both one and two years postoperatively, as polypharmacy progressed, these scores significantly deteriorated. Regarding the satisfaction scores of ZCQ, they significantly worsened with the progression of polypharmacy. The JOABPEQ scores showed significant improvements across all three groups in the pre- and postoperative comparisons. However, in the comparison among the three groups, postoperative scores worsened as polypharmacy progressed.
Discussion:
In this study, we retrospectively examined the characteristics of older LSS patients with polypharmacy or hyper-polypharmacy. Essentially, in terms of HRQOL, there were no significant changes in their scores at baseline even as polypharmacy progressed. However, postoperatively, the more polypharmacy progressed, the worse these scores became. These results suggest that the greater the progression of polypharmacy, the lower the effectiveness of surgery. The number of preoperative prescribed drugs should not be a deterrent factor for surgical intervention, as scores significantly improved postoperatively, even in cases of polypharmacy or hyper-polypharmacy. However, it is important for patients and their physicians to consider the potential negative impact of increasing medication use on surgical outcomes during the preoperative informed consent process.