di , 20/07/2021

Since its inception, blockchain has proven to have the ability to unleash a technical and economic revolution. It all began with the big data’s phenomenon: high volume, access and speed of information processing, which increased the value of collecting and processing personal data. The next step was to place services in the cloud (cloud computing), which made it possible to use all this information from big data and process it more efficiently. And then, one day, blockchain appeared.

For those less familiar with the notion of blockchain, this technology consists of a chain of digital transactions (chained digital records) that are incorporated into an immutable structure that is confirmed and verified by the members who share the information. There is no centralized storage of information and it cannot be deleted or copied. Much of the fundamental characteristics of the blockchain reside in its ability to increase the security and traceability of the information contained in the chain, which makes it essential for the digital health sector.

Blockchain includes the potential to revolutionize the health sector, since it places the patient (user) in the center of the scene, allowing her or him to directly control the information protocol at all times, as well as being able to customize the distribution of the personal data on the shared network.

The companies that are in charge of exploiting this technology will have to find a way to adapt to the current operating conditions that the use of blockchain entails in the sector, but notably they will have to provide trust and transparency to users. A similar example can be a pedagogical step that has been taken in the European Union with the GDPR (General Data Protection Regulation, 2018), which has created awareness among users about the importance of managing personal data.

In blockchain we host the enormous technological hope of maintaining a single, unalterable and longitudinal record that each patient can demand at all times in terms of security and privacy. This respect is appropriate between the patient and the doctor and the insurance company, as well as any other actor in the health ecosystem.

Applications and benefits

Blockchain has the vocation to be present in most layers of the health ecosystem. The benefits that exist are multiple. The system will make it possible to unify the multiple identities of the patient through different health platforms, giving the user the possibility to decide and control (consent) the access and processing of information by any actor (Despotou et al., 2020).

By unifying the information, registers can be made compatible throughout the different platforms, thus facilitating the interoperability between the systems, a situation that today is a real obstacle. Faced with user concerns about the way their data is processed, blockchain allows the removal of certain intermediaries, and the user maintains the direct access to the distribution list.

Transaction costs can be reduced as a consequence of the reduction in intermediation. Blockchain allows an update of the patient’s information through the different networks where the information has been hosted.

Thanks to the blockchain, the use of smart contracts can be extended in a generalized way by different service providers in a consistent way.

Other applications of the blockchain consist of being able to ensure the validity of drug supply chain, notably in developing countries, in order to avoid the circulation of counterfeit products. This can also help to guarantee the quality of the product and the respect for the cold chain, for example.

Consent, control and access

This giant step for the patient could be revolutionary. Blockchain will allow to identify and authenticate the patient’s and its personal information (eventually, sensitive/genetic content), as well as its registry of medical prescriptions (Zhang et al, 2018) in a large number of health platforms. With one important caveat: Patients may give (or deny) access to different borrowers, or allow limited access to certain information, in relation to particular treatments or pathologies. Annotations, certifications, exam results and prescriptions will be stored on the blockchain. The system can also ensure the monitoring of patients treatments, reminders and, of course, payments for services (transactions through smart contracts).

Some limitations

It is likely that, over time, market players will know how to circumvent the specific limits of blockchain, since currently the system presents some limitations.

One of them is linked to the novelty of technology. The system probably will still have to operate for about ten years in order to fully adapt to the specific characteristics of the market. The use of cryptocurrencies (and, for instance, NFTs – non-fungible tokens – more recently) will allow us to learn in detail the dangers and eventual limitations of the system and the ways to foresee solutions.

An important obstacle that blockchain finds in the digital health sector is linked to the mistrust that large pharmaceutical companies generate in a large part of the patients. Not only as a consequence of the great benefits of these companies, but also because of their dominant positions in the drug market and, little by little, personal data (Pérez Campillo, 2020). Added to this is the lack of transparency in their processes and the monopoly that they naturally exercise in the management of pathologies.

It should also be noted that the mere use of the blockchain does not free operators from cybersecurity compliance. Risks persist, especially at the level of user terminals and providers. Complementary protocols should be established, especially since the current databases will remain in force for a longer time, and it will be necessary to guarantee a certain level of compatibility and security between both systems (Evangelatos, 2020).

Blockchain may allow a democratization of the circulation of patients’ personal information, as well as increasing the user’s power over the final control over such information. At the same time, it is likely that by increasing the level of data in circulation, this could lead to fairer and more dynamic health services. An example of balance to consider will be the next rollout of vaccine passports, which will imply, in many ways, a restriction to people’s individual freedoms (Murphy, 2021).

Blockchain could bring trust and transparency on health data management: companies must create solutions that understand the importance of the respect of personal data and that can be properly used by patients. This will imply the creation of value from the multiplication of data units shared by users via blockchain, thanks to the trust in the system. This can be done on the basis of the understanding by patients that thanks to the increase in the volume of health data, it will be possible to obtain better diagnoses and more appropriate therapies.

The key for healthcare professionals and technology developers will be to reconcile the technological potential with the need for security and privacy of patients’ personal data.


  • https://www.newmedicaleconomics.es/innovacion-y-nuevas-tecnologias/la-vacunacion-y-blockchain-oportunidades-desafios-y-privacidad/
  • https://www.computerworld.es/tendencias/la-oms-se-apoya-en-el-blockchain-para-crear-certificados-de-vacunacion-contra-la-covid19
  • Evangelatos, Nikolaos ; Özdemir, Vural ; Brand, Angela, Blockchain for digital health : Prospects and challenges. In OMICS: A Journal of Integrative Biology. May2020, Vol. 24 Issue 5, p237-240. 4p. , 2020 – p237-241
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  • Heather Murphy, A look at Covid-19 Vaccine ‘Passports’ Passes and apps around the globe.
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