Blockchain-Based Secure Sharing of Patient Medical Records between Hospitals

Abstract

Interoperability of patient files between hospitals continues to present significant obstacles. Health systems frequently utilize central EHR systems that could suffer malfunctions, data breaches, and unauthorized access by third parties. Not only does this jeopardize patient confidentiality, but it also hinders the efficient operations of hospital processes.Blockchain technology is viewed as a prospective remedy for the issue. Blockchain keeps its data differently, allowing users to store data securely and make changes difficult. In this study, we analyze research works published between 2016 and 2023 regarding blockchain-based hospital-to-hospital data exchange.The methodologies differ widely: there are cases where researchers use smart contracts in Ethereum, build a system on Hyperledger Fabric, and deploy IPFS. Moreover, certain studies incorporate encryption methods, machine learning algorithms, and more. In summary, the results show that blockchain allows for improved data protection and transparency while giving patients more control over their personal information. Still, some issues persist, such as scalability, expenses, integration with existing infrastructure, and adherence to GDPR and HIPAA requirements. For future work, more improvements are necessary. For instance, zero-knowledge proofs, cybersecurity measures for new technologies, and using artificial intelligence to audit and validate smart contracts may be promising solutions.

Introduction

The rapid expansion of digital healthcare systems has improved medical data collection but also introduced serious challenges related to security, interoperability, and centralized control of Electronic Health Records (EHRs). Centralized healthcare databases are vulnerable to cyberattacks, data tampering, and system failures, while interoperability issues between hospital platforms often disrupt continuity of care. To address these problems, blockchain technology has emerged as a promising alternative because of its decentralized structure, immutability, and ability to improve trust in data sharing.

Existing research explores multiple blockchain-based healthcare solutions. Systems such as MeDShare improve access control and auditing using permissioned blockchains and smart contracts, while hybrid approaches combining Ethereum and IPFS reduce storage costs by keeping large medical files off-chain. Other methods include attribute-based encryption for fine-grained access control and privacy-preserving machine learning models that operate on encrypted data. However, these approaches still face limitations such as high computational overhead, scalability issues, dependency on external storage systems, and incomplete privacy protection.

The literature also highlights broader challenges in healthcare blockchain adoption, including regulatory uncertainty, limited real-world deployment, and performance constraints of public blockchains. As a result, permissioned blockchains are generally preferred for healthcare due to higher throughput, better privacy control, and compliance suitability.

Methodologically, most systems combine blockchain with smart contracts to manage access control, patient consent, and data integrity. These smart contracts enable automated permission handling, secure logging of medical data access, and enforcement of predefined rules. Despite significant progress, the field still requires more scalable, efficient, and interoperable solutions to fully support secure healthcare data exchange in real-world environments.

Conclusion

The literature review highlights twelve studies conducted on the use of blockchain technology for secure data exchanges and access control with respect to the interests of patients in their health records. It proves that blockchain can solve the issues of security, auditing, and access control in healthcare settings. Permissioned blockchains are preferable because of their transaction capability and better privacy. A new approach called the hybrid architecture is applied to big data exchange, allowing data to be stored externally and hashed internally through blockchain technology. Nonetheless, there are still problems, like checking the authenticity of the input data and scaling blockchain technology. Potential future directions involve Zero-Knowledge Proofs, fast blockchain algorithms for IoT devices, smart contracts\' security, interoperability across chains, and post-quantum cryptographies for blockchain in healthcare.

References

[1] A. Azaria, A. Ekblaw, T. Vieira, and A. Lippman, \"MedRec: Using blockchain for medical data access and permission management,\" in Proc. 2nd International Conference on Open and Big Data (OBD), Vienna, Austria, 2016, pp. 25–30. [2] Q. Xia, E. B. Sifah, K. O. Asamoah, J. Gao, X. Du, and M. Guizani, \"MeDShare: Trust-less medical data sharing among cloud service providers via blockchain,\" IEEE Access, vol. 5, pp. 14757–14767, 2017. [3] G. Zyskind, O. Nathan, and A. Pentland, \"Decentralizing privacy: Using blockchain to protect personal data,\" in Proc. IEEE Security and Privacy Workshops (SPW), San Jose, CA, USA, 2018, pp. 180–184. [4] P. Zhang, J. White, D. C. Schmidt, G. Lenz, and S. T. Rosenbloom, \"FHIRChain: Applying blockchain to securely and scalably share clinical data,\" Computational and Structural Biotechnology Journal, vol. 16, pp. 267–278, 2018. [5] A. Dubovitskaya, Z. Xu, S. Ryu, M. Schumacher, and F. Wang, \"How blockchain could empower eHealth: An application for radiation oncology,\" in VLDB Workshop on Data Management and Analytics for Medicine and Healthcare (DMAH), Los Angeles, CA, USA, 2019, pp. 3–13. [6] A. Shahnaz, U. Qamar, and A. Khalid, \"Using blockchain for electronic health records,\" IEEE Access, vol. 7, pp. 147782–147795, 2019. [7] D. C. Nguyen, P. N. Pathirana, M. Ding, and A. Seneviratne, \"Blockchain for secure EHRs sharing of mobile cloud based E-health systems,\" IEEE Access, vol. 7, pp. 66792–66806, 2020. [8] M. Shen, X. Tang, L. Zhu, X. Du, and M. Guizani, \"Privacy-preserving support vector machine training over blockchain-based encrypted IoT data in smart cities,\" IEEE Internet of Things Journal, vol. 6, no. 5, pp. 7702–7712, 2020. [9] A. Farouk, A. Alahmadi, S. Ghose, and A. Mashatan, \"Blockchain platform for industrial healthcare: Vision and future opportunities,\" Computer Communications, vol. 154, pp. 223–235, 2020. [10] A. H. Mayer, C. A. da Costa, and R. D. R. Righi, \"Electronic health records in a Blockchain: A systematic review,\" Health Informatics Journal, vol. 26, no. 2, pp. 1273–1288, 2021. [11] M. A. Rahman, M. M. Rashid, M. S. Hossain, E. Hassanain, M. F. Alhamid, and M. Guizani, \"Blockchain and IoT-based cognitive edge framework for sharing economy services in a smart city,\" IEEE Access, vol. 7, pp. 18611–18621, 2022. [12] O. Ali, A. Jaradat, A. Kulakli, and A. Abuhalimeh, \"A comparative study on smart healthcare: Blockchain technology and AI in healthcare applications,\" Journal of Medical Systems, vol. 47, no. 1, pp. 1–12, 2023. [13] S. Nakamoto, \"Bitcoin: A peer-to-peer electronic cash system,\" Bitcoin.org, 2008. [Online]. Available: https://bitcoin.org/bitcoin.pdf [14] V. Buterin, \"A next-generation smart contract and decentralized application platform,\" Ethereum White Paper, 2014. [Online]. Available: https://ethereum.org/en/whitepaper/

Copyright

Copyright © 2026 Radhika A Jujare, Ramya Gowda D V, Sahana M. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.