Proposing New Blockchain Challenges in eHealth

Abstract

Background: The blockchain technology has reached a great boom in the health sector, due
to its importance to overcome interoperability and security challenges of the EHR and EMR
systems in eHealth.
Objective: The main objective of this work is to show a review of the existing research
works in the literature, referring to the new blockchain technology applied in ehealth and
exposing the possible research lines and trends in which this technology can be focused.
Methods: The search for blockchain studies in eHealth field was carried out in the following
databases: IEEE Xplore, Google Scholar, Science Direct, PubMed, Web of Science and
ResearchGate from 2010 to the present. Different search criteria were established such as:
“Blockchain” AND (“eHealth” OR “EHR” OR “electronic health records” OR “medicine”)
selecting the papers considered of most interest.
Results: A total of 84 publications on blockchain in eHealth were found, of which 18 have
been identified as relevant works, 5.56% correspond to the year 2016, 22.22% to 2017 and
72.22% to 2018. Many of the publications found show how this technology is being
developed and applied in the health sector and the benefits it provides.
Conclusion: The new blockchain technology applied in eHealth identifies new ways to
share the distributed view of health data and promotes the advancement of precision
medicine, improving health and preventing diseases.

Full text

SYSTEMS-LEVEL QUALITY IMPROVEMENT
Proposing New Blockchain Challenges in eHealth
Susel Góngora Alonso
1
&Jon Arambarri
2,3
&Miguel López-Coronado
1
&Isabel de la Torre Díez
1
Received: 13 December 2018 / Accepted: 31 January 2019
#Springer Science+Business Media, LLC, part of Springer Nature 2019
Abstract
The blockchain technology has reached a great boom in the health sector, due to its importance to overcome interoperability and
security challenges of the EHR and EMR systems in eHealth. The main objective of this work is to show a review of the existing
research worksin the literature, referring to the new blockchain technology applied in ehealth and exposing the possible research
lines and trends in which this technologycan be focused.The search for blockchain studies in eHealth field was carried out in the
following databases: IEEE Xplore, Google Scholar, Science Direct, PubMed, Web of Science and ResearchGate from 2010 to the
present. Different search criteria were established such as: BBlockchain^AND (BeHealth^OR BEHR^OR Belectronic health
records^OR Bmedicine^) selecting the papers considered of most interest. A total of 84 publications on blockchain in eHealth
were found, of which 18 have been identified as relevantworks, 5.56% correspond to the year 2016, 22.22% to 2017 and 72.22%
to 2018. Many of the publications found show how this technology is being developed and applied in the health sector and the
benefits it provides. The new blockchain technology applied in eHealth identifies new ways to share the distributed view of health
data and promotes the advancement of precision medicine, improving health and preventing diseases.
Keywords Blockchain .Challenges .eHealth .Electronic health records (EHRs)
Introduction
eHealth is a technology that is becoming increasingly impor-
tant over time, from remote access to medical records, such as
Electronic Health Records (EHR) or Electronic Medical
Records (EMR), to the exchange of real-time data from dif-
ferent body sensors in patients [1]. The importance of eHealth
is its ability to provide patients, worldwide, access to their
medical data and real-time monitoring of their health with
the evolution of IoT and connected objects. Improved com-
munication between patients and health professionals, there-
fore, effectiveness in treatments and health monitoring, greater
access to medical care and less pressure on public health bud-
gets [2].
EHR is a standardized information model, which allows
integration among multiple health care providers, and this
integration is considered its main advantage [3]. EHR has
several benefits, ranging from supporting medical prescrip-
tions, improving the management of disease and contributing
to the reduction of serious medication errors. However, EHR
has limitations with respect to interoperability, with the secu-
rity of data exchanged between health organizations, or with
the non-incorporation of data on patient welfare [4]. Hence, in
the context of eHealth, blockchain emerges as a highly secure
and decentralized network platform of several computers
called nodes; changing the way medical information is stored
and shared. It facilitates the work, monitors the security and
accuracy of data and also reduces the maintenance cost [5].
The main advantage of blockchain technology in
healthcare organizations is the management of patients
EMRs. Nowadays, patient information is stored safely in
This article is part of the Topical Collection on Systems-Level Quality
Improvement
*Isabel de la Torre Díez
isator@tel.uva.es
Susel Góngora Alonso
suselgongoraalonso@gmail.com
Jon Arambarri
jarambarri@virtualwaregroup.com
Miguel López-Coronado
miglop@tel.uva.es
1
Department of Signal Theory and Communications, and Telematics
Engineering, University of Valladolid, Paseo de Belén, 15,
47011 Valladolid, Spain
2
Virtual Ware Labs Foundation, Bilbao, Spain
3
Basauri, Spain
Journal of Medical Systems (2019) 43:64
https://doi.org/10.1007/s10916-019-1195-7

many places, dispersed among many institutions, hospitals
and insurance providers, without full access to a shared patient
database [6]. Health records stored in blockchain could allow
patients to make their structured data available to researchers.
All these factors have the potential to reducestorage costs and
increase efficiency, possibly even by integrating automatic
systems of insurance payment through the use of intelligent
contracts (automatic execution contracts with terms of agree-
ment between the parties written directly on code lines) built
as a layer on blockchain [7].
Blockchain technology has gained great popularity in
recent years in different sectors, one of these fields being
health. This popularity is due to its unique characteristics
such as: absence of centralized control, a high degree of
anonymity and a consensus distributed over decentralized
networks. Hence, in this work we present a review of the
state of the art regarding blockchain technology in
eHealth, in order to obtain an overview of topic and ex-
pose the possible research lines and trends in which this
technology can be focused.
There are similar studies that demonstrate the viability
of our research, such as: in [8] the authors determine the
current challenges of EMR systems and potential solu-
tions in order to show the interoperability and security
challenges of the different EMR systems that they use
blockchain technology, [9] the authors present the poten-
tial applications of technology and highlight the
blockchain challenges in medical care and [10]theau-
thors investigate different blockchains structures in the
administration and exchange of EHR and EMR to allow
patients, hospitals, clinics and other medical stakeholders
to share data with each other and increase interoperability.
The methodology used in this review is described below.
Afterwards, the results obtained the discussion of them and
the final conclusions of this research work will be finalized.
Methodology
In this paper was developed a review of the existing re-
search works in literature regarding the use of blockchain
in eHealth, with publication dates from 2010 to the present.
Different scientific databases were used to carry out the
review, such as: IEEE Xplore, Google Scholar, PubMed,
Science Direct, Web of Science and ResearchGate. Table 1
shows the different search criteria used for the review. The
databases used cover the largest amount of research in
fields such as eHealth.
Certain requirements for the inclusion of a document
were taken into account, such as: 1) The document must
be written in English. 2) Blockchain studies applied to
eHealth. 3) Those studies focused on how blockchain is
applied in other non-ehealth sectors are eliminated. The
selection process of the articles was carried out by reading
titles and abstract of results obtained by one of authors,
and the articles were classified by reading their abstracts
and the full article when necessary. Fig. 1show the search
strategy used in the review.
Of the 84 publications found 53 were duplicated or with
irrelevant title for this research, the remaining 31 studies were
read and analyzed their abstracts to determine which were of
interest, obtaining as a result 18 documents which gave rise to
relevant contributions. In the following section shows the
most relevant papers found.
Results
Blockchain technology has gained considerable progress
in recent years in fields such as health. The medical data
contains personal and sensitive information that must be
preserved. In the early stages of design and development,
several organizations have designed novel technologies
that have the latency to maximize medical data, such as
heterogeneous transparency and operational capabilities
[5]. Blockchain offers a new and promising distributed
frameworktoamplifyandsupport the integration of
health care information in a variety of uses and stake-
holders [11].
By reviewing the literature we found a total of 18 relevant
papers related to the blockchain technology applied in
eHealth. Of which 5.56% correspond to the year 2016,
22.22% to 2017 and 72.22% to 2018 demonstrating the nov-
elty of the Blockchain technology applied to eHealth. Fig. 2
shows the statistics of the relevant paper found from 2010 to
the present and Fig. 3shows the percentages of each topic in
which results of this review are divided.
Below is show a summary of results obtained in the litera-
ture review (See Table 2).
In [6] propose a novel protocol to achieve the preservation
of patient privacy, called Pseudonym Based Encryption with
Different Authorities (PBE-DA) applying the Blockchain con-
cept in health communication entities in an eHealth platform,
with the objective to comply with the requirement of structure
distributed in eHealth records system. The results showed the
development of the protocol and its validation.
In [16] the authors propose a secure and scalable access
control system for confidential information. Employed secure
cryptographic techniques (encryption and digital signatures)
to ensure efficient access control to confidential shared
datasets using an authorized blockchain for enhanced security
and a closely monitored system. They designed a blockchain-
based data exchange scheme that allows users/data owners to
access EHR from a shared repository after their identities and
cryptographic keys have been verified. The results show that
64 Page 2 of 7 J Med Syst (2019) 43:64

the system succeeds where traditional methods of passwords
access control, firewalls and intrusion detection systems fail.
In [19] the authors present an approach to solve the prob-
lem of managing access control in eHealth. Access control is a
special complex task in electronic health, since resources and
data are distributed among different installation and institu-
tions. To overcome this complexity, they propose an approach
that takes advantage use of blockchain to store transactional
information about eHealth records and access control policies.
The results in general show that approach is viable, which
offers several advantages when compared with existing
systems.
In [22] the authors propose a DABS scheme for
Blockchain in healthcare, which provides an efficient verifi-
cation of EHR data authenticity and identity of the signer.
They also describe a holistic on-chain and off-chain collabo-
rative storage system for efficient storage and verification of
EHR data. This blockchain-based storage system ensures that
stored and shared EHR data is not constrained cannot be ver-
ified, and combination of on-chain and off-chain storage ef-
fectively realizes the secure sharing of large-scale distributed
EHR data. The experimental results show that the proposed
protocol is effective and practical.
In [25] propose a secure EHR system based on attri-
butes and blockchain technology. In the system, they used
attribute-based encryption (ABE) and identity-based en-
cryption (IBE) to encrypt medical data, using the
identity-based signature (IBS) to implement digital signa-
tures. This greatly facilitates the management of the sys-
tem and does not need to introduce different cryptograph-
ic systems for different security requirements. In addition
blockchain techniques guarantee the integrity and trace-
ability of medical data.
In [26] the authors propose a blockchain-based secure and
privacy-preserving personal health information (PHI) sharing
(BSPP) scheme for diagnosis improvements in e-Health sys-
tems. In this case, the private blockchain and consortium
blockchain are used. The private blockchain is responsible
for storing the PHI, while the consortium blockchain keeps
records of the PHI safe indexes. Block generators must pro-
vide a conformance test to add new blocks to blockchain,
which guarantees the availability of the system. The results
show that the proposed protocol can meet the security
objectives.
Discussion
One of the blockchain main advantages compared to other
models of distributed databases is the integration of data
Fig. 1 Flow Diagram
Table 1 Searches conducted on the different academic databases
Databases Search criteria Search fields
IEEE Xplore BBlockchain^AND (BeHealth^OR BEHR^OR Belectronic health records^OR Bmedicine^)Babstract^
Google Scholar BBlockchain^AND (BeHealth^OR BEHR^OR Belectronic health records^OR Bmedicine^)Btitle^
PubMed BBlockchain^AND (BeHealth^OR BEHR^OR Belectronic health records^OR Bmedicine^)Btitle/abstract^
Science Direct BBlockchain^AND (BeHealth^OR BEHR^OR Belectronic health records^OR Bmedicine^)Babstract, title, keywords^
Web o f Science BBlockchain^AND (BeHealth^OR BEHR^OR Belectronic health records^OR Bmedicine^)Btitle^AND Btopic^
ResearchGate BBlockchain^AND (BeHealth^OR BEHR^OR Belectronic health records^OR Bmedicine^)Btitle/abstract^
J Med Syst (2019) 43:64 Page 3 of 7 64

processing, which guarantees correction and security in a sin-
gle protocol, is implemented algorithmically and minimizes
the human factor [21]. The ability to verify the authenticity of
EHR data and signer identity for EHR data is fundamental for
the practical deployment of blockchain in medical care [22].
Identify new ways to share the distributed view of health data
and promote advancement of precision medicine, health im-
provement and disease prevention [28]. Below we show the
main challenges that are discussed in this review.
Challenges
The Blockchain technology offers a platform that could be
used for many potential applications in medical care. It has
the potential to improve security in remote patient monitoring
systems and automate the delivery of health-related notifica-
tions in a manner compatible with HIPAA [29]. You can solve
current problems with poorly managed patient data by adding
clean and formatted data to EHR and EMR, which allows
healthcare to use big data with more reliable information,
leading to more meaningful results.
Blockchain is a technology based on public key cryptogra-
phy and hashing mechanisms as a means to track historical
transactions related to distributed patient records while pre-
serving the data confidentiality, integrity and availability.
Ensuring that records are not lost or modified falsified or
accessed incorrectly.
There are important obstacles to overcome in order for
blockchain to reach its maximum potential and be applied
in medical care, the most important problems are technol-
ogy scalability and data access controls [7]. Some of
greatest advantages that application of this technology
could provide in health care are: access to a large quantity
of anonymous health data that could be used for medi-
cines personalized development, rationalization of medi-
cal insurance costs and health, as well as the improvement
of public health policies. Along with data availability on
health care providers, this type of patient participation
could generate a new era in medical care.
The blockchain technology could also help with other as-
pects of medical care, such as improving the insurance claim
or other administrative processes within the healthcare net-
works and making available to biomedical researchers, popu-
lation data related to health [30].
Conclusion and future work
The purpose of this review was to provide an overview of the
state of art in research on blockchain in eHealth and expose
the research lines and trends of this new technology in this
field. The results obtained show us a very innovative technol-
ogy from which we obtained relevant papers with publication
date from 2016.
Fig. 2 Relevant papers found in
the last 10 years
Fig. 3 Percentages of topics found in the review, related with blockchain
in eHealth
64 Page 4 of 7 J Med Syst (2019) 43:64

Table 2 Studies of the bibliographic review related to Blockchain in eHealth
Authors Year of
publication
Objective of the Study Results
Azaria et al. [12] 2016 They propose a novel decentralized registry management
system called MedRec to manage EMRs, using
blockchain technology. The system provides patients
with a complete and immutable record and easy access
to their medical information through providers and
treatment centers.
- The results demonstrated an innovative approach to the
management of medical records, providing
interoperability and accessibility through a complete
registry. MedRec allows the exchange of patient data
and incentives for medical researchers to maintain the
system.
Cunningham
&Ainsworth
[13]
2017 They present a system that allows personalized control of
the access of third parties to EHR of patients, which
allows people to specify when and how their records are
accessed for research purposes.
- The results show that the use of Ethereum blockchain
technology based on intelligent contract to implement
this system, allows it to operate in a verifiable, reliable
and openly auditable environment, crucial features for
the advancement of health information systems.
Dubovitskaya
et al. [14]
2017 The authors propose a framework on the management and
exchange of EMR data for care of cancer patients based
on blockchain.
They implement the framework in a prototype that
guarantees privacy, security, availability and detailed
access control over EMR data.
- The results show that the proposed study can
significantly reduce the response time to share EMR,
improve decision making for medical care and reduce
the overall cost.
Magyar [15] 2017 They present a study of how blockchain technology can
help solve the problem of secure data storage and
guarantee its availability at the same time in an EHR
system.
- The new technology solves an essential problem of
access to data without endangering personal privacy.
- It opens new opportunities for automatic personal
monitoring devices and takes a step towards the
participation of new service providers.
Xia et al. [16) 2017 The authors propose a secure and scalable access control
system for confidential information using blockchain.
- The results show that the system succeeds where
traditional methods of passwords access control,
firewalls and intrusion detection systems fail.
Badr, Gomaa, &
Abd-Elrahman
[6]
2018 They propose a novel protocol to achieve the preservation
of patient privacy, called PBE-DA applying the
Blockchain concept in an eHealth platform.
- The results showed the protocol development and its
validation.
Dagher et al. [17] 2018 They propose a framework based on blockchain for
secure, interoperable and efficient access to EHR by
patients, suppliers and third parties, while preserving
the privacy of patients’confidential information.
The framework, called Ancile, uses smart contracts in
blockchain based on Ethereum for greater control of
data access, and uses advanced cryptographic
techniques for greater security.
- The results show a blockchain system that achieves a
high level of decentralization while recognizing that
some nodes must be of a higher authority.
- It offers an important preservation of the data privacy
and integrity.
Da Conceição
et al. [18]
2018 The authors analyze blockchain technology and smart
contracts in scenarios related to access, administration
and interoperability of data for domain of specific
medical attention.
They propose the implementation of large-scale
information architecture to access EHR based on
intelligent contracts as mediators of information.
- His main contribution is the framing of data privacy and
accessibility problems in medical care as well as
proposal of an integrated architecture based on
blockchain.
Dias et al. [19] 2018 The authors present an approach to solve the problem
of managing access control in eHealth.
- The results in general show that the approach is viable,
which offers several advantages when compared with
existing systems.
Kaur et al. [5] 2018 The authors propose a platform based on Blockchain
thatcanbeusedtostoreandmanageEMRinacloud
environment.
-This study offers a summary of the framework, the
internal work and protocols for management of
heterogeneous health data.
Mikula &
Jacobsen [20]
2018 The authors propose a system for the identities and
accesses management using blockchain.
They propose a prototype based on an open source
blockchain framework called Hyperledger Fabric to
demonstrate the viability of the system.
- The results confirm that identity and access management
can be achieved in a decentralized, efficient and secure
manner.
- The proposed concept was applied and discussed in a
case of use with EHR of health sector.
Novikov et al.
[21]
2018 They present a model of health system decentralized
infrastructure, a scheme of the distributed data registry
for creation of patient electronic medical card. An
algorithm has been developed for use of smart contracts
in the health system using blockchain.
- The results of research demonstrate the effectiveness of
blockchain technology for storing patient EHR.
J Med Syst (2019) 43:64 Page 5 of 7 64

Challenges such as the scalability, security and profitability
of blockchain technology will require more research before
large-scale production implementations. The future of this
technology in health and other industries needs more research
and development. However, a distributed system that elimi-
nates intermediaries has a substantial potential to interrupt
many current processes in medical care and research.
Blockchain offers an opportunity to make possible the ef-
ficient exchange of information between the interested parties
and the protection of the patient’sprivacy,aswellastoguar-
antee the integrity of the data. Unresolved problems such as
acceptance, regulation and ethics should be considered for the
use of blockchain technology.
As the health industry moves towards models focused
mainly on patients, the use of blockchain technology emerges
as a viable solution, since it allows storing and managing
electronic health records in an efficient and safe way.
Blockchain’s potential for health care depends to a large
extent on the acceptance of new technology within the health
care ecosystem to create technical infrastructure. Leveraging
this technology has potential of connect fragmented systems
to generate ideas and better assess the care value. In the long
term, a national blockchain network for EMR can improve
efficiency and support better health outcomes for patients.
Hence, we propose as future work design and implement a
platform using blockchain to share EHRs among various med-
ical and health institutions in a region of Spain, taking into
account the security and privacy protocols for the handling of
patient data. Facilitating that in a future blockchain can be
seen as component of a system in which patients act as ad-
ministrators of their own data.
Acknowledgments This research has been partially supported by
European Commission and the Ministry of Industry, Energy and
Tourism under the project AAL-20125036 named BWetake Care: ICT-
based Solution for (Self-) Management of Daily Living^.
Compliance with ethical standards
Conflict of interest The authors declare that they have no conflict of
interest.
Ethical approval This article does not contain any studies with human
participants or animals performed by any of the authors.
Publisher’sNoteSpringer Nature remains neutral with regard to jurisdic-
tional claims in published maps and institutional affiliations.
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