After multiple attempts and delays at becoming fully digital24, the NHS has now released a ten-year plan1, in which it introduces the basis for a new twenty-first century service model. This includes digitally equipping all primary and outpatient care, and empowering patients to access, manage, and contribute to digital information and services, which includes incorporating data added by patients themselves. In addition, they pave the way to improve quality of life for those with long-term conditions by the use of connected and interoperable devices.
Achieving interoperability, however, depends on patients taking control of their data and deciding on how it will be used. Data ownership would need to be shifted from the government to patients, and while this would require extensive reengineering of legacy systems, it would hopefully incentivise patients to become active agents in their own care. By contributing data to the system, they would be able to get the best possible treatment25,26, exemplifying the notion of patient-centred care. The re-engineering of systems would need to keep in mind legal restrictions, such as the recently introduced General Data Protection Regulation. Under this law, patients may request for their data to be erased27. However, with a Blockchain, a record of the data’s previous existence would always be maintained on the chain.
In addition to abiding by legal restrictions on data use, Blockchain would need to guard against intruders. Not only do data breaches cause damage by the loss of data to hackers, but they also have a negative impact on the public perception of the healthcare field, and threaten to hinder future research through more stringent regulatory restrictions28. While a Blockchain is more secure than older methods29, most are still susceptible to a ‘51% attack’, in which a majority of mining nodes collude to rewrite the chain structure30. Users must trust that at least 50% of mining nodes would not want to violate the immutability of the Blockchain. The use of a ‘permissioned’ (as opposed to permissionless) Blockchain, however, can allow a healthcare system to rule out any possibility of this style of attack. This method limits those who can run full nodes, issue transactions, execute smart contracts and read transaction history to approved computers and users. This feature therefore increases the integrity of the system, as well as guarding against hackers, and strengthens the system beyond its robust foundation of public-key cryptography.
Taking into account these concerns, a more practical solution than expecting patients themselves to take control of their lifelong health record increasingly seen in the field, is an independent company-managed electronic health record database. These typically employ Blockchain to secure patient data and to empower patients in a way that has not previously been possible.
The concept of Blockchain-based medical record management has been considered and implemented on a small scale by a number of companies7,31,32; however, only very few healthcare systems have begun to incorporate the technology into their nationwide infrastructure. Of those, Estonia is at the forefront, securing more than one million citizens’ records in a ledger in collaboration with Guardtime. The system has proven that interoperability is an achievable goal, and demonstrated that the ability to analyse data has helped the government to become aware of and more easily track health epidemics33.
Additional benefits of using Blockchain for health records include the ability to analyse the information with artificial intelligence. This will be more easily able to determine population trends, which can be used to achieve population level health. However, it will require careful integration, to allow sufficient integration without compromising privacy of patient data or security against hackers.
Further, data gathered from mobile applications, wearable sensors and other recent forms of technology could also contribute important information to the system, allowing physicians to create specialised treatment plans based on more frequent data. This is increasingly possible in an environment where continuous and detailed data is already being collated by the Internet of Things. It is also thought that such continuous health data would engage a patient more in their health care, improving compliance and long-term outcomes. Open source software means that different health IT systems could integrate the use of Blockchain as they wish, making this a versatile opportunity. The use of wearable technology and the incorporation of the Internet of Things into AI-based data analysis would bring forth additional benefits with a larger index of accurate data points.
Some administrative matters must be considered when implementing a Blockchain. Removing duplicates when consolidating legacy systems is costly and time-consuming. Once in place, it is vital that users of the system input good quality information; otherwise, the trustworthiness of the system arising from Blockchain’s immutability and decentralisation give way to the lack of accurate information, creating a critical point of failure. Nevertheless, the costs associated with educating users on how to make the most use out of the system would lead to returns in health outcomes. In the primary stages, usefulness will still depend on the end user experience, and so the requirement of hiding the complexities of Blockchain behind a sufficiently user-friendly interface becomes paramount to ensuring successful uptake. These primary stages will establish the most effective systems.
As various healthcare providers and companies update their record management systems on different timescales, it is necessary to consider how multiple ledgers might interact with one another. We outline below one potential framework to demonstrate the integration of several Blockchain ledgers managed by independent healthcare providers (Fig. 3). Another architecture would involve a system of records managed by independent companies on behalf of patients, with healthcare providers given data access but not the privilege of management. In either case, as individual providers introduce their own ledger systems using Blockchain’s API, they could connect to a wider network of Blockchain-based providers, allowing patients to visit different hospitals, or switch to a different healthcare data management company. This would allow doctors more easy access to a comprehensive set of data, with the patient’s explicit consent.