The following is a summary of “Role of Serum Brain-Derived Neurotrophic Factor as a Biomarker of Chronic Pain in Older Adults,” published in the April 2025 issue of European Journal of Pain by Ortolá et al. 

Researchers conducted a retrospective study to examine serum brain-derived neurotrophic factor (BDNF) levels in chronic pain (CP) while accounting for sex, mental health, and key confounders.   

They analyzed data from 1,932 community-dwelling adults aged ≥ 65 years, randomly selected from the Spanish general population and measured the serum BDNF levels using ELISA. The CP characteristics were evaluated through the European Chronic Pain Survey and categorized using International Classification of Primary Care, Second Edition (ICPC-2) codes from electronic medical records. The linear regression models were applied and adjusted for sociodemographic, lifestyle, and clinical factors and performed stratified analyses by sex and depression status (defined by Geriatric Depression Scale score, recent physician diagnosis, or antidepressant use).   

The results showed mean BDNF levels were 18.55 (5.66) ng/mL in 962 men and 19.39 (5.77) ng/mL in 970 women. Most individuals reported pain in a median of 3 sites [interquartile range: 2–4]. Among 511 individuals with CP, musculoskeletal pain was most common (n = 446), followed by nociplastic (n = 71), neuropathic (n = 54), visceral (n = 51), and vascular pain (n = 22). In 1,639 non-depressed participants, women with severe or interfering pain had lower BDNF levels compared to those without CP [β coefficient (95% CI): −2.62 ng/mL (−5.03, −0.22) and −3.09 ng/mL (−4.71, −1.47), respectively], a pattern not seen in men. Among 293 men with depression, severe and interfering pain were associated with reduced BDNF levels [−5.12 ng/mL (−9.26, −0.99) and −4.95 ng/mL (−8.29, −1.61)], while no such associations appeared in depressed women. Similar patterns were noted for musculoskeletal and nociplastic pain types.   

Investigators concluded that serum BDNF was a favorable biomarker for CP; its reliability for gauging pain severity relied on patient sex and depression status, factors that needed consideration to improve its accuracy and clinical relevance in CP evaluation. 

Source: onlinelibrary.wiley.com/doi/10.1002/ejp.70014