BMI changes by occupational physical activity change in period-specific samples. The Tromsø Study 1974-2016.
| Change occupational physical activity examinations 1 and 2 | ||||||
| Period-specific samples* | Total | Persistently inactive | Persistently active | Active to inactive | Inactive to active | Pequality |
| Tromsø 1–3 (1974–1987)# | n | |||||
| Tromsø 2–3 (1979–1987) | 3570 | 1033 | 1805 | 366 | 366 | |
| BMI (kg/m2) | Mean 95% CI | 0.48 0.39 to 0.57 | 0.48 0.41 to 0.54 | 0.49 0.35 to 0.64 | 0.57 0.43 to 0.71 | 0.68 |
| Tromsø 2–4 (1979–1995) | n | |||||
| Tromsø 3 and 4 (1986–1995) | 9679 | 2512 | 5179 | 665 | 1323 | |
| BMI (kg/m2) | Mean 95% CI | 1.12 1.05 to 1.19 | 1.15 1.10 to 1.20 | 1.12 0.99 to 1.26 | 1.07 0.98 to 1.17 | 0.50 |
| Tromsø 3–5 (1986–2002) | n | |||||
| Tromsø 4 and 5 (1994–2001) | 3827 | 1315 | 1915 | 223 | 374 | |
| BMI (kg/m2) | Mean 95% CI | 0.96 0.86 to 1.05 | 0.96 0.87 to 1.04 | 1.02 0.79 to 1.25 | 0.91 0.73 to 1.09 | 0.90 |
| Tromsø 4–6 (1994–2008) | n | |||||
| Tromsø 5 and 6 (2001–2008) | 2212 | 884 | 985 | 166 | 177 | |
| BMI (kg/m2) | Mean 95% CI | 0.12 −0.004 to 0.24 | 0.12 0.01 to 0.24 | 0.15 −0.13 to 0.43 | 0.07 −0.20 to 0.35 | 0.98 |
| Tromsø 5–7 (2001–2016) | n | |||||
| Tromsø 6 and 7 (2007–2016) | 1146 | 481 | 501 | 60 | 104 | |
| BMI (kg/m2) | Mean 95% CI | 0.07 −0.11 to 0.25 | 0.35 0.17 to 0.53 | 0.14 −0.36 to 0.64 | 0.21 −0.17 to 0.60 | 0.20 |
Data are adjusted for sex, birth year, smoking, education and BMI at examination 2, and are shown as adjusted mean and 95% CI. Pequality is the main difference between groups.
*Period-specific samples include all participants for that period (ie, these samples do not add up to the overall cohort (Tromsø 1–7), which includes participants with their three most recent attendances),
†Tromsø 1 included only men.
BMI, body mass index.