Apple Watch uses AI to detect high blood pressure without cuffs

Apple Watch Series 11 introduces an AI-powered blood pressure notification feature that can alert users to potential hypertension without requiring a traditional cuff-based monitor. The FDA-approved feature uses artificial intelligence to analyze existing sensor data and could help address the global health crisis where half of the 1 billion people with high blood pressure remain undiagnosed.

How it works: Apple developed the feature by applying machine learning models to data from 100,000 participants in its heart and movement study launched in 2019.

• The AI algorithm analyzes signals from the watch’s main heart-related sensor and matches patterns with traditional blood pressure measurements.
• After multiple layers of machine learning, Apple validated the algorithm through a specific study of 2,000 participants.
• The feature will work on Apple Watch Series 9 and newer models, extending beyond just the Series 11.

What you should know: The notification system doesn’t directly measure blood pressure but serves as an early warning system.

• The FDA-approved feature notifies users they may have high blood pressure and encourages them to use a traditional cuff for accurate measurement and consult a doctor.
• Apple plans to roll out the feature to more than 150 countries starting Friday.
• The company’s privacy measures limit data collection outside of large-scale studies, but these studies provide valuable insights for identifying health signals.

Why this matters: The feature addresses a significant gap in hypertension detection, as many people only encounter blood pressure cuffs during doctor visits.

• Early detection could help reduce related conditions such as heart attacks, strokes, and kidney disease, according to Ami Bhatt, chief innovation officer of the American College of Cardiology.
• Sumbul Ahmad Desai, Apple’s vice president of health, emphasized the power of large-scale studies: “Those studies are incredibly powerful” for enabling scientific discovery of health signals.

What experts are saying: Medical professionals emphasize both the potential benefits and limitations of the new feature.

• Bhatt noted that “Apple appears to have been careful to avoid false positives that might alarm users,” though she stressed the feature is no substitute for traditional measurements and professional diagnosis.
• However, Bhatt warned of another risk: “There is also the risk of false reassurance — those who don’t get an alert may wrongly assume they don’t have hypertension.”