Abstract
Knee osteoarthritis (OA) is a major cause of chronic pain and disability in older adults, yet scalable home-based interventions remain limited, partly due to the lack of clinically effective digital solutions. This study is the first fully powered randomized, double-blind, sham-controlled trial to test a digitally delivered, home-based protocol combining transcranial direct current stimulation (tDCS) and mindfulness-based meditation (MBM) for knee OA pain. A total of 208 participants were randomized to active tDCS + MBM, active tDCS + sham MBM, sham tDCS + active MBM, or double sham; they completed ten 20-min sessions over 2 weeks. Knee pain intensity was measured at baseline, post treatment, and monthly for 3 months. Although both active tDCS groups improved, the difference between the combined tDCS + MBM intervention and tDCS alone was not statistically significant. Benefits were not sustained at 3 months. These findings offer the first evidence that a remotely supervised, digitally delivered tDCS + MBM intervention can rapidly reduce knee OA pain, supporting future personalized and extended treatment studies. Clinical trial registration: ClinicalTrials.gov NCT04375072 (registered May 7, 2020).
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All data supporting the findings of this study are summarized in this published article. Requests for additional de-identified data will be reviewed by the corresponding author on a case-by-case basis and may require institutional and ethical approval.
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No custom code was used in this study.
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Acknowledgements
We thank Dr. Alejandro Chaoul for his valuable contributions as a consultant on the meditation component of this project. His expertise in mind -body practices informed the development and implementation of the intervention. This work was supported by the National Institute of Nursing Research (R01 NR019051-01, 2020 -2025; R01NR019051-03S1, 2022 -2025), the National Institute on Aging (R03 AG093555-01, 2025 -2027), and the University of Arizona College of Nursing.
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J.P. designed the study, developed the research questions, and drafted the manuscript. C.L. reviewed and edited the full manuscript, with particular attention to statistical analysis and reporting of results. L.L., M.J.F., I.T., S.D., L.P., and J.H. reviewed the draft and provided constructive feedback throughout the revision process. H.M. conducted the data analyses and contributed to the statistical interpretation and reporting of findings. HA contributed to the study design, conceptual framework, and secured the R01 funding that supported the project.
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Park, J., Lee, C., Lin, L. et al. A randomized trial of a digitally delivered, home-based neuromodulation and mindfulness intervention for pain management in older adults with knee osteoarthritis. npj Digit. Med. (2026). https://doi.org/10.1038/s41746-026-02577-7
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DOI: https://doi.org/10.1038/s41746-026-02577-7


