Descriptive characteristics for the Tromsø Study (Tromsø6) and the Birkebeiner Ageing Study (BiAS) study participants
| Baseline characteristics | Tromsø6 (n=1867) | BiAS (n=505) | P value |
| Age (years) | 70 (67–75) | 68 (66–71) | <0.001 |
| Height (cm) | 174.5 (170.1–178.8) | 178.0 (175.0–182.0) | <0.001 |
| Weight (kg) | 81.2 (73.4–89.9) | 75.0 (70.0–80.0) | <0.001 |
| BMI (kg/m2) | 26.8 (24.4–29.1) | 23.5 (22.2–24.8) | <0.001 |
| Number of Birkebeiner races completed | – | 14 (7–27) | |
| Number of achieved Birkebeiner medals | – | 6 (0–21) | |
| Total years of systematic endurance training | – | 36 (19.0–49.0) | |
| % (n) | % (n) | ||
| Education | <0.001 | ||
| Primary/Secondary school | 35.6 (646) | 16.6 (83) | |
| High school | 35.8 (649) | 42.2 (211) | |
| College/University | 28.6 (518) | 41.2 (206) | |
| Smoking status | <0.001 | ||
| Current | 15.4 (281) | 0.8 (4) | |
| Former | 60.6 (1103) | 37.9 (191) | |
| Never | 24.0 (436) | 61.3 (309) | |
| Frequency of alcohol consumption | <0.001 | ||
| Never | 14.2 (259) | 9.4 (46) | |
| 1–4 times per month | 64.1 (1169) | 73.0 (356) | |
| 2–3 times a week | 15.6 (284) | 14.6 (71) | |
| 4 times or more per week | 6.2 (113) | 3.1 (15) | |
| Coronary heart disease | 24.3 (444) | 3.6 (18) | <0.001 |
| Diabetes | 8.5 (154) | 0.8 (4) | <0.001 |
| Currently or previously on antihypertensive medication | 40.5 (729) | 15.7 (76) | <0.001 |
| Self-reported physical activity | <0.001 | ||
| Sedentary | 19.4 (314) | 0.2 (1) | |
| Light | 58.0 (941) | 9.8 (48) | |
| Moderate | 21.9 (355) | 51.0 (251) | |
| Vigorous | 0.7 (12) | 39.0 (192) | |
| ≥1 AF risk factor present | 86.0 (1605) | 35.1 (177) | <0.001 |
Values are presented as median (25th and 75th percentile) for continuous variables and as percentages for categorical variables. AF risk factor variable: one or more of the following: BMI ≥25 kg/m2, current smoker, current use of antihypertensive medication, diabetes and coronary heart disease.
AF, atrial fibrillation; BMI, body mass index.