A smart ring that detects high blood pressure? This is exactly what Oura is planning: in a new study, the company wants to develop an algorithm that will enable the Oura Ring 4 to reliably identify high blood pressure in the future. The approach could add a valuable health component to wearables – without the need to carry a traditional cuff.
Highlights
- Oura launches a study to develop an algorithm to detect high blood pressure based on PPG sensors.
- Participants in the USA (aged 22 and over) can provide data via a questionnaire – according to Oura, calibration via cuff is not initially necessary.
- The aim is to make the feature available to users of Oura Ring 3 and 4 after regulatory approval.
- The Oura Ring 4 already has improved sensor technology and should enable more accurate health monitoring than older models.
Study with PPG data instead of cuff measurement
The new approach is based on PPG (photoplethysmography) – i.e. optical measurement of light absorption in the bloodstream. Oura wants to combine data from the ring with additional information from a short questionnaire in order to train a deep model for high blood pressure predictions using machine learning. What is surprising is that, according to a report by Notebookcheck, no external calibration using a conventional blood pressure device is planned – at least in the first phase of the study.
To date, valid medical blood pressure measurement via a smart device has been rare and usually fraught with limitations. The Huawei Watch D2 (€ 319.00 *) is currently an exception, as it offers a certified cuff measurement. Other devices attempt to estimate blood pressure using heart rate and PPG readings – but the results are often less reliable and need to be recalibrated regularly.
Oura wants to use an indirect approach with the Oura Ring 4 (€ 399.00 *). Instead of using an adopted calibration of measured values, a learning-based model based on many measured values and user data is used. This should ensure that high blood pressure is “recognized”. The study is currently only running for users in the USA who are at least 22 years old.
Opportunities, limitations and regulatory hurdles
A feature such as high blood pressure detection in wearables would have great potential: early detection, continuous monitoring, health awareness. A gentle warning function would be particularly attractive for users who already have risk factors.
But the challenges are considerable:
- Accuracy & validity: whether a purely algorithmic model without calibration reliably arrives at the classic cuff value remains an open question – especially in the case of individual differences.
- Data basis & bias: The study is currently only open in the USA – the algorithm must later be extended to different populations globally.
- Regulatory approval: In order for functions such as “high blood pressure detected” to actually be released for all users, regulatory approval is required – similar to the path that Apple has already taken with its health functions, for example.
- Liability and user communication: The platform must clearly communicate that such a function does not replace a medical device, but is an assistance function.
- Availability & rollout: The feature will only be available to users with Oura Ring 3 (€ 219.00 *) and Ring 4 once it has been fully completed and approved.
Conclusion
Oura’s study, which aims to use the Ring 4 to detect high blood pressure in the future, is ambitious and could make wearables more relevant to health. The approach of combining PPG data with questionnaire data using machine learning is innovative – technically challenging, but potentially revealing. It remains to be seen whether the result will ultimately receive the necessary accuracy and approval. As soon as the hypertension feature is available, Oura will offer a corresponding option to Ring 3 and 4 users (following successful regulatory approval).
