Long-term exposure to high blood pressure increases the risk of atrial fibrillation, especially in young people

Scientists analyzed how the cumulative impact of elevated blood pressure (BP) over a lifetime affects the likelihood of developing atrial fibrillation (AF) in adults of different age groups. The results of the study, published in the Journal of the American Heart Association, showed that early and long-term elevated BP carries a much higher relative risk of AF in young people compared to older people.

Why is this important?

• Early prevention in young people: it is middle-aged people with prolonged, albeit mild, increase in blood pressure who are in the group with the highest relative risk of MA.
• New criteria for BP monitoring: Clinicians should pay attention not only to one-time readings, but also to the patient's long-term "calculated" BP profile.
• Monitoring perspectives: The use of wearable sphygmomanometers and cumulative AUC algorithms may aid early identification of those requiring aggressive antihypertensive therapy.

"Our results show that the 'cumulative dose' of high blood pressure has a more damaging effect at a young age. This should change the approach to monitoring and controlling hypertension, with a focus on long-term follow-up," comments Dr Anders Larsson, lead author.

Research methods

The study was based on data from a large multicenter cohort study of adult patients, in which BP was measured repeatedly over several years. For each participant, a cumulative BP “curve” (in mm Hg years) was calculated — the integral of BP level over time — and linked to the subsequent registration of a new episode of AF. In this case, all patients were divided into age subgroups (e.g., <50 and ≥50 years), which allowed us to assess the age dependence of the effect.

Key Results

• In younger participants (<50 years), each additional 1000 mm Hg year of cumulative systolic BP was associated with an increase in the relative risk of AF of approximately 80–100%, whereas in older participants (≥50 years), this increase was approximately 20–30%.
• A similar relationship was observed for cumulative diastolic BP, although the absolute risk values were lower than for systolic BP.
• Statistical analysis showed that the association between cumulative BP and AF was significantly stronger at younger age (p < 0.01 for the interaction “age × cumulative BP”).

Interpretation and clinical conclusions

According to the authors, the higher sensitivity of young people to the effects of long-term elevated blood pressure may be explained by a lesser “adaptation” of the vessels and heart to hypertension at early stages and a more pronounced inflammatory and remodeling response of the myocardium in this group. This means that:

1. Early diagnosis and control of blood pressure is especially important for adults under 50 years of age—even moderate but prolonged increases in blood pressure can lead to a significant increase in the risk of AF.
2. Primary prevention strategies should take into account the 'blood burden' (cumBP) rather than relying solely on single BP measurements in the clinic.
3. Individualization of hypertension therapy: in young patients, more aggressive early reduction of blood pressure to values below 130/80 mm Hg is advisable to reduce the cumulative effect.

Below are the key statements from the study's authors:

• “This is the first prospective, multicenter study that takes into account not just single blood pressure measurements, but the cumulative ‘blood burden’ (cumBP) throughout adulthood,” said lead author Dr. Li Qiang. “This approach allowed us to find that younger patients (<50 years) are particularly vulnerable: every additional 1000 mmHg year of systolic BP in this group doubled the risk of atrial fibrillation.”
• “We found a strong age x cumulative pressure interaction effect: in older people (≥ 50 years), the same increase in cumBP systolic pressure resulted in only a 20–30% increase in the relative risk of AF, whereas in younger people it was around 80–100%,” explains study co-author Professor Karen Murphy, an expert in arrhythmia epidemiology.
• “Our results highlight that hypertension prevention needs to start much earlier than is commonly thought: even moderately elevated blood pressure in the 30s and 40s can create a ‘deposit’ of cumBP that will then ‘fire’ as fibrillation in the 60s,” says clinical cardiologist Emily Zhou, PhD. “For younger patients, it’s important not just to treat blood pressure as it happens, but to actively monitor its historical fluctuations and intervene more aggressively at the first sign of a deviation from the norm.”
• "From a clinical practice perspective, the age cut-off of 50 years appears to be a critical threshold," concludes senior author Professor Richard O'Neill. "We recommend reviewing current guidelines and introducing a 'cumulative' BP measure into primary prevention programmes to enable hypertension to be identified and treated at an early stage."

The authors emphasize that although the absolute risk of AF increases with age, the relative benefit of BP control is greatest in young and middle age, when the potential survival time after an averted AF episode is greatest. This study supports the need for earlier initiation of BP monitoring and intervention to reduce the burden of arrhythmias and associated complications in the population.