Blockchain brings secure patient record transfer closer to reality

For almost a decade, hospitals have been waiting for electronic health records (EHRs) to usher in a shiny new era of standardisation and high quality health care. But while federal laws and incentive programmes have made health care data more accessible in some regions, the vast majority of hospital systems around the globe still can’t easily (or safely) share their data. As a result, doctors are spending more time typing than talking to patients. The number one thing those doctors would change? Streamlining the EHR process. And the most popular strategy circulating among health care technologists is blockchain.

Blockchain security explained

Blockchain is the distributed accounting platform that makes cryptocurrencies like bitcoin possible. But wait, you say! Isn’t that like what the dark internet uses? While blockchain is best known for powering bitcoin, it’s really a generic tool to keep secure data in a distributed, encrypted ledger, and control who has access to that ledger. Rather than having one central administrator who acts as a gatekeeper to data - a list of digital transactions - there’s one shared ledger, but it’s spread across a network of synchronised, replicated databases visible to anyone with access. Which gives it unprecedented security benefits. Hacking one block in the chain is impossible without simultaneously hacking every other block in the chain’s chronology.

This makes blockchain incredibly appealing to the doctors and hospitals that need secure access to a patient’s entire health history. “Now is probably the right time in our history to take a fresh approach to data sharing in healthcare,” says John Halamka, chief information officer at a Boston based hospital. For the past decade, Halamka has been responsible for healthcare data standards in the US, first under the Bush and then the Obama administration. He sees a blockchain- underwritten future in which a patient’s every health care interaction goes into a ledger every provider can see. “The EHRs may be very different and come from lots of different places,” Halamka says, “but the ledger itself is standardised.”

Every time a digital transaction takes place, bits of code group it into an encrypted block with other transactions happening at the same time. For bitcoin, this would be a flurry of buying and selling. For EHRs, it might be all the things that happen to you on a doctor’s visit (blood work, a new prescription, maybe some X-rays). Then people validate the transactions - in healthcare, likely a physician or pharmacist trusted with an access key. Then the software timestamps each validated block and adds it to a chain of older blocks, in chronological order. The sequence shows every transaction made in the history of that ledger, whether it be bitcoin sales or a knee replacement procedure.

It’s a chain of blocks ... Blockchain.

Halamka gives a simple example: prescriptions. One medical record shows a patient takes aspirin. In another it says they’re taking Tylenol, with another saying they’re on Motrin and Lipitor. The problem today is that each EHR is only a snapshot; it doesn’t necessarily tell the doctor what the patient is taking right now. But with blockchain, each prescription is a deposit, and when the doctor discontinues a medication, they make a withdrawal. Looking at a blockchain, a doctor wouldn’t have to comb through all the deposits and withdrawals - they would just see the balance (or what the present prescription provides). And crucially for patient privacy and security, hospitals and pharmacies don’t have to send data back and forth to see it. They just all have to point to the same common ledger. So does it work? For prescriptions, at least, initial results are promising. Halamka recently teamed up with researchers at the MIT Media Lab to test a blockchain application pilot called MedRec. Team- lead Ariel Ekblaw put the authentication log to work at their hospital, tracking six months of in-patient and out-patient medication data with MedRec code deployed through virtual machines at MIT. They recorded blood work, vaccination history, prescriptions, and other therapeutic treatments, simulating data exchange between institutions by using two different databases within their hospital. The results were so positive that Ekblaw is already starting to plan more pilots with larger networks of hospitals. MedRec is still an early prototype, not ready for widescale deployment any time soon. But government health officials in the US see its future promise on a global scale.