D’Souza, Ryan S.

Introduction Although the prevalence of chemotherapy-induced peripheral neuropathy (CIPN) has been reported, the proportion of patients with CIPN who report chronic moderate-to-severe neuropathy or chronic painful neuropathy remains poorly understood, despite its significant impact on patients’ quality of life and treatment outcomes. Methods A systematic review and meta-analysis were conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The primary outcome was the pooled prevalence of chronic (≥3 months) moderate-to-severe CIPN or painful CIPN among patients diagnosed with CIPN. Estimates from each study were transformed using a double-arcsine transformation and pooled in a meta-analysis using an inverse variance heterogeneity model. Subgroup analysis was conducted based on geographical region, sex, chemotherapy regimen, primary cancer type, and funding source; metaregression analysis was conducted based on study design, human development index (HDI), and publication year. Results 76 studies from 29 countries, encompassing 13 635 patients with CIPN, were included. Among patients diagnosed with CIPN, the pooled prevalence of those reporting chronic moderate-to-severe CIPN or painful CIPN was estimated at 47.76% (95% CI 37.50 to 58.08; 95% prediction interval 24.68–71.84). Substantial heterogeneity was observed across studies ( I² =97.45%; 95% CI for I 2 97.15 to 97.72). Subgroup analysis revealed that patients treated with platinum-based agents and taxanes had the highest prevalence of chronic moderate-to-severe CIPN or painful CIPN (44.47% and 55.68%, respectively), and among primary cancers, those with breast cancer, multiple myeloma, and lung cancer reported the highest prevalence of chronic moderate-to-severe CIPN or painful CIPN (61.31%, 53.55%, and 50.85%, respectively). Study design, HDI, and publication year were non-significant moderators of prevalence estimates. Based on our Grading of Recommendations, Assessment, Development, and Evaluation assessment, the certainty of evidence was considered “very low.” Sensitivity analysis restricted to studies explicitly measuring painful CIPN (40.78%; 95% CI 29.08 to 52.74) or moderate-to-severe CIPN (49.04%; 95% CI 37.16 to 60.95) yielded similar prevalence estimates. Conclusion This study provides the first comprehensive global estimate of the prevalence of chronic moderate-to-severe CIPN or painful CIPN, highlighting its significant burden on patients worldwide. The variation in prevalence across geographical regions, chemotherapy regimens, and primary cancers underscores the need for tailored management strategies and further research to address potential disparities.

Background Randomized clinical trials (RCTs) are considered the gold standard for evaluating the efficacy of healthcare interventions. However, conflicts of interest (COIs) can compromise the scientific integrity in these trials. This study characterized COIs in RCTs on spinal cord stimulation for chronic pain, focusing on the prevalence, disclosure, and monetary value of COIs. Methods This cross-sectional study analyzed RCTs published from January 1, 2013 to July 27, 2023. Primary outcomes included the presence, disclosure, and monetary value of COIs, while secondary outcomes assessed the presence of direct/indirect COIs, sponsor access to data, and associations between COIs and select variables, including journal impact factor, publication year, and study outcomes. Results Of 38 RCTs, 30 (78.9%) reported COIs. On average, 35.6% of authors per RCT had at least one COI, with a mean of 0.7 COIs per author. The mean annual monetary value of COIs was US$41,157.83 per author per RCT. 29 RCTs (76.3%) had undisclosed COIs, with an average of 24.2% of authors per RCT having undisclosed COIs. Sponsor access to data was reported in 67.6% of RCTs. No associations were observed between the mean percentage of authors with COIs and the monetary value of COIs and select dependent variables (impact factor, publication year, and study outcomes). Conclusions A substantial majority of RCTs reported COIs with many authors having undisclosed conflicts, highlighting the need for stringent COI disclosure guidelines to maintain research integrity. Expanding COI registry systems globally and increasing non-industry funding are crucial steps toward enhancing transparency and reducing biases in medical research.