Categorization of chronic pain subtypes and contributing biomarkers in heart failure

Aims: Pain is common among adults with heart failure (HF), but pain subtypes and associated biomarkers are understudied. The aims were to: 1) characterize chronic pain severity, neuropathic pain quality, locations, and subtypes; and 2) compare pain severity and levels of biomarkers among pain subtypes. An exploratory aim was to correlate levels of biomarkers with pain severity. Methods: This pilot descriptive study included cross-sectional data from 60 adults with HF and chronic pain. Pain was evaluated using the PainDETECT questionnaire. Blood biomarkers included interleukin (IL)-10, IL-18, IL-1β, IL-33, IL-6, IL-8, tumor necrosis factor (TNF)-α, brain-derived neurotrophic factor, leptin, adiponectin, and C-reactive protein. Descriptive statistics, Chi-square test of homogeneity, one-way analysis of variance, and Spearman correlation were used for analyses. Results: The mean age was 70.45 (SD 7.92) years. The sample consisted of 63.3% women and 65.0% White race. Participants primarily reported nociceptive pain only (73.3%) with fewer reporting neuropathic pain only (6.7%) and mixed pain (20.0%). Current and 4-week mean pain severity scores were highest in the mixed pain subtype (p both