CHA₂DS₂-VASc score of 1 – what does it mean?
⚠︎ Learning page – classification and study figures only, no treatment recommendation.
In short
A CHA₂DS₂-VASc of 1 lies on a scale from 0 to 9 points. In the nationwide Danish cohort of Olesen et al. (2011) it belongs to the "intermediate risk" category (0 = low, 1 = intermediate, 2–9 = high).
With 1 point, the rate of hospital admission or death due to thromboembolism in the first year was 2.01 per 100 person-years (95% CI 1.70–2.36), and 1.45 per 100 person-years over 10 years. 8,203 people in the cohort (11.2%) had this score.
The figures describe groups in the cited studies, not the risk of an individual person. This page contains no treatment or management recommendation.
How a score of 1 comes about
There are 6 different combinations that add up to exactly 1 point. Examples:
- hypertension (1), male
- age 65–74 years (1), male
- female sex (1)
- diabetes mellitus (1), male
- heart failure (1), male
- vascular disease (1), male
Where no age is given, age is under 65 years. Stroke/TIA/thromboembolism and age 75 years or older score 2 points each; all other criteria score 1 point each.
Which factor provides the point makes a difference
Olesen et al. analysed the event rate at 1 point separately for each single risk factor (year 1, per 100 person-years):
- heart failure: 1.50 (95% CI 0.37–5.98)
- hypertension: 2.14 (95% CI 1.46–3.15)
- diabetes mellitus: 3.47 (95% CI 1.65–7.27)
- vascular disease: 0.75 (95% CI 0.24–2.33)
- age 65–74 years: 2.88 (95% CI 2.29–3.62)
- female sex: 1.24 (95% CI 0.89–1.73)
The authors conclude that the risk associated with a given score depends on the factors that make it up. Some confidence intervals are wide because subgroups were small.
What the studies describe
Lip et al. described CHA₂DS₂-VASc in 2010 as the "Birmingham 2009 schema" in a cohort of 1,084 patients with atrial fibrillation from the Euro Heart Survey. As a scoring system, it showed an increase in thromboembolism rate with increasing score (P for trend = .003); no thromboembolic events occurred among those classified as low risk.
Olesen et al. tested the score in 2011 in 73,538 people in Denmark with non-valvular atrial fibrillation who received neither vitamin K antagonists nor heparin (1997–2006). Thromboembolism included ischaemic stroke, TIA, peripheral artery embolism and pulmonary embolism.
All scores at a glance
| Score | Category (Olesen 2011) | Event rate, year 1* | Share of cohort |
|---|---|---|---|
| 0 | low risk | 0.78 | 8.7 % |
| 1 | intermediate risk | 2.01 | 11.2 % |
| 2 | high risk | 3.71 | 17.4 % |
| 3 | high risk | 5.92 | 23.6 % |
| 4 | high risk | 9.27 | 18.9 % |
| 5 | high risk | 15.26 | 12.2 % |
| 6 | high risk | 19.74 | 5.8 % |
| 7 | high risk | 21.50 | 1.9 % |
| 8 | high risk | 22.38 | 0.4 % |
| 9 | high risk | 23.64 | 0.1 % |
* Hospital admission or death due to thromboembolism per 100 person-years, Danish cohort without vitamin K antagonists or heparin (Olesen 2011, table 2).
Calculate it yourself
Enter the criteria in the CHA₂DS₂-VASc score calculator – it runs only in your browser.
FAQ
Is a CHA₂DS₂-VASc of 1 high?▾
In the classification of Olesen et al. (2011), a score of 1 belongs to the "intermediate risk" category. The event rate in the first year was 2.01 per 100 person-years in this cohort.
Which CHA₂DS₂-VA corresponds to a CHA₂DS₂-VASc of 1?▾
CHA₂DS₂-VA (ESC 2024) omits only the sex category. For men it is also 1; for women it is 0.
What does "1/9" mean?▾
1 out of a maximum of 9 points. The maximum is 9 because the two age bands (65–74 and ≥ 75 years) are mutually exclusive.
References
- Lip GY et al. Refining clinical risk stratification for predicting stroke and thromboembolism in atrial fibrillation using a novel risk factor-based approach: the Euro Heart Survey on atrial fibrillation. Chest 2010;137:263–72. · PubMed
- Olesen JB et al. Validation of risk stratification schemes for predicting stroke and thromboembolism in patients with atrial fibrillation: nationwide cohort study. BMJ 2011;342:d124. · PubMed · full text (PMC)
- Van Gelder IC et al. 2024 ESC Guidelines for the management of atrial fibrillation. Eur Heart J 2024;45:3314–414. · PubMed
Learning page for medical education only: classification and figures reported in the cited sources, no treatment or management recommendation, not for use in patients; not a medical device. Last updated: 10/2026 · Dr. Pascal Bafteh