Almost 5 % of those in their mid-60s have atrial fibrillation, according to Trygve Berge‘s PhD thesis.

MAIN RESULTS:

1. 6.4 % of men and 2.4 % of women in Akershus aged between 63 and 65 years have atrial fibrillation.
2. Obesity, hypertension and heart failure are linked to higher likelihood of having atrial fibrillation.
3. Screening for atrial fibrillation among high-risk 65-year-olds did not identify many unknown cases.

THESIS DEFENCE:

Thesis: Atrial fibrillation: Epidemiology and screening at 65 years – Design and cross-sectional analysis of the Akershus Cardiac Examination (ACE) 1950 Study cohort
Candidate: Trygve Berge
Time: March 21 at 13:15
Place: University of Oslo, Domus Academica: Gamle festsal
Link to university website

SUMMARY:

(1) The Akershus Cardiac Examination 1950 study (ACE 1950) was performed between 2012 and 2015, and aims to investigate development and progression of cardiovascular disease and stroke in middle-aged men and women. The cohort study includes 3,706 women and men born in 1950 and living in Akershus County. In his first article, Berge presents the baseline examinations, including cardiac and carotid artery ultrasound, ECG, cognitive tests, blood and urine sampling, spirometry, blood pressure and body composition.

Almost 65 % of the eligible men and women participated, with an approximately even sex distribution. The participants will be followed up over several years, potentially through both questionnaires and national health registries.

(3) 6.4 % of the men and 2.4 % of the women in ACE 1950 had confirmed atrial fibrillation. This is higher than what is previously found in 63-65-year-olds. The higher prevalence in men could be explained by a higher burden of known risk factors among men than women, and being a man was not in itself associated with higher likelihood of atrial fibrillation. On the other hand, hypertension, obesity, height, heart failure, renal dysfunction and a family history of atrial fibrillation were independent predictors of having atrial fibrillation.

The results are based on single ECG measurements of all the ACE 1950 participants, and does not necessarily detect all cases of non-permanent atrial fibrillation. 5.2 % of the participants reported atrial fibrillation, but Berge and co-workers were only able to detect fibrillation in 4.1 %. Furthermore, the study revealed atrial fibrillation in 12 participants who were unaware they had it, resulting in a total prevalence of 4.5 %.

(2) Two-week screening for atrial fibrillation in participants with high cardiovascular risk revealed unknown atrial fibrillation in less than 1 %. The 1,510 included participants had either known cardiovascular disease, diabetes or hypertension.

The participants wore a handheld one-lead “thumb ECG” that performed recordings for 30 seconds twice daily or when the participants experienced symptoms. The results indicate that screening for atrial fibrillation in this group of middle-aged adults might not be of great value.

REFERENCES:

(1) Berge, T., Vigen, T., Pervez, M. O., Ihle-Hansen, H., Lyngbakken, M. N., Omland, T., Steine, K., Røsjø, H., Tveit, A., & ACE 1950 Study Group. (2015). Heart and brain interactions–the Akershus Cardiac Examination (ACE) 1950 Study design. Scandinavian Cardiovascular Journal, 49(6), 308-315.

(2) Berge, T., Brynildsen, J., Larssen, H. K. N., Onarheim, S., Jenssen, G. R., Ihle-Hansen, H., Christophersen, I. E., Myrstad, M., Røsjø, H., Smith, P. & Tveit, A. (2017). Systematic screening for atrial fibrillation in a 65-year-old population with risk factors for stroke: data from the Akershus Cardiac Examination 1950 study. EP Europace, 20(FI_3), f299-f305.

(3) Berge, T., Lyngbakken, M. N., Ihle-Hansen, H., Brynildsen, J., Pervez, M. O., Aagaard, E. N., Vigen, T., Kvisvik, B., Christophersen, I. E., Steine, K., Omland, T., Smith, P., Røsjø, H., & Tveit, A. (2018). Prevalence of atrial fibrillation and cardiovascular risk factors in a 63–65 years old general population cohort: the Akershus Cardiac Examination (ACE) 1950 Study. BMJ open, 8(7), e021704.