Do wearables actually help people with cardiovascular disease? What the latest evidence says

Walk down most city streets and roughly three in ten passers-by are wearing a smart watch, many of them equipped with sensors that record heart rhythm, take an electrocardiogram (ECG), measure oxygen saturation and chart sleep stages. The wearables industry argues these devices are transformative for people with cardiovascular disease. STAT News set out to test that claim, surveying the major meta-analyses published in the past two years.

Three questions guided the review: do wearables catch atrial fibrillation (AFib) earlier? Do they raise physical activity enough to reduce cardiovascular risk? And do they improve hypertension management? The answers differ.

The evidence is strongest for AFib detection. The FDA-cleared ECG features in Apple Watch, Fitbit and Samsung Galaxy Watch can pick up undiagnosed AFib in adults who have no symptoms. A 2025 JAMA Cardiology meta-analysis cited by STAT pooled 12 randomised controlled trials and found that screening programmes roughly doubled the rate of new AFib diagnoses in low- to moderate-risk people over 65. The authors stressed, however, that whether those earlier diagnoses translate into fewer strokes is still unproven.

The picture is murkier for physical activity. A 2024 BMJ meta-analysis found smart-watch wearers with cardiovascular disease added 1,300–1,800 daily steps on average in the first three months, but the effect faded sharply after six. Behaviour-change researchers say the device alone is not enough — the durable benefit appears when wearables are combined with coaching, cardiac rehabilitation or scheduled phone follow-up.

Hypertension management is the most contested area. Innovations like the Samsung Galaxy Watch's cuff-free blood-pressure estimate drew attention, but validation studies have shown the device can read inaccurately, especially at the upper end of the range. The American Heart Association says optical wrist-based pressure estimates are not yet suitable for clinical decisions; the validated arm-cuff remains the gold standard.

Another important limit is equity. Stanford and Mount Sinai researchers cited by STAT have shown that smart watches can systematically misread pulse and oxygen saturation on darker skin tones. Relying on wearable data to guide treatment risks producing worse decisions for minority patients — a concern several large academic medical centres now flag in their adoption guidance.

There is also alarm fatigue. False-positive AFib alerts can trigger panic and unnecessary emergency room visits. A May JAMA Internal Medicine study found that 68% of patients who came to the ER because of an Apple Watch alert had no active AFib. Cardiologist Steven Lubitz argues a smart-watch alert should be treated as a prompt to check, not a medical decision in itself.

For heart failure patients, the outlook is more promising. Body-composition data and resting-night heart-rate trends give clinicians a chance to spot deteriorating patients before they need admission. A 2025 Cleveland Clinic pilot reported a 28% lower 30-day readmission rate for heart failure patients on remote monitoring versus standard care.

A few practical factors emerge. Specialists say wearables add genuine value in three settings: an active patient who responds to feedback; a person over 65 at risk of silent AFib; a heart failure patient enrolled in remote monitoring. A wrist monitor alone, doctors emphasise, does not replace a clinic visit, a validated cuff or medication adherence.

The overall message is that smart watches are becoming part of medical practice but are not an "everything is fine" signal. Used well, they offer early warning and behavioural support; used poorly, they generate needless anxiety and avoidable visits. The question, STAT concludes, is shifting from "do wearables help?" to "which patient, which question, which monitoring programme?"