Table 2

Mean annual weight change and proportion of participants by weight-change categories according to sample characteristics

NMean annual weight change (kg)p Value*Annual weight-change categoryp Value†
Loss (%)
n=7685 (17%)
Maintenance (%)
n=26 922 (60%)
Gain (%)
n=10 430 (23%)
Sex
 Male20 9110.210.019186022<0.001
 Female24 1260.27166024
Age (years)
 45–5415 0310.41<0.001145728<0.001
 55–6415 2070.26166024
 65–7496190.14186319
 75–844549−0.07246115
 85 plus631−0.26325613
Education
 No school cert38570.140.016225425<0.001
 School cert13 6350.23185824
 Trade/cert/dip15 0590.28166023
 University degree12 4860.24166322
Physical activity tertile
 Low11 8960.190.025195625<0.001
 Moderate15 9180.25176023
 High16 7510.27156222
Physical impairment
 None/minor34 8130.250.080166223<0.001
 Moderate36620.21225325
 Severe18480.13264628
Smoking status
 Never26 3150.21<0.001166222<0.001
 Past15 9530.25185824
 Current26340.50184933
  • *p Value of analysis of variance tests. †p Value of χ2 tests.

  • Physical impairment was measured using the Medical Outcomes Score-Physical Functioning (MOS-PF), which is equivalent to items from the physical functioning scale of the SF-36 health survey (none/minor=score of 75–100; moderate=score of 50–74; and severe=score of <50). No weight change is defined as an annual weight change of between −1 and 1 kg. Weight loss is defined as >−1 kg annual weight change. Weight gain is defined as >1 kg weight change.