Introduction
Materials and methods
Study population
Main measures
Statistical methods
Univariate trajectory analysis
Joint trajectory analysis
Association between joint trajectories and depression
Results
Sample characteristics
Total | Major depression in wave 5 | No major depression in wave 5 | Test of difference | ||||
---|---|---|---|---|---|---|---|
N
| % |
N
| %a
|
N
| %a
|
p value | |
Total subjects in wave 2b
| 6371 | – | 121 | 1.9 | 6164 | 98.1 | – |
Sexb
| |||||||
Men | 2797 | 43.9 | 38 | 1.4 | 2725 | 98.6 | 0.005 |
Women | 3574 | 56.1 | 83 | 2.4 | 3439 | 97.6 | |
Age groupb
| |||||||
< 35 years | 640 | 10.0 | 21 | 3.3 | 608 | 96.7 | 0.002 |
35–49 years | 2150 | 33.8 | 49 | 2.3 | 2089 | 97.7 | |
≥ 50 years | 3581 | 56.2 | 51 | 1.4 | 3467 | 98.6 | |
Marital statusb
| |||||||
Single | 1238 | 19.6 | 31 | 2.5 | 1187 | 97.5 | 0.090 |
Married/cohabiting | 5069 | 80.4 | 90 | 1.8 | 4916 | 98.2 | |
Childrenb
| |||||||
Children at home | 2813 | 44.7 | 69 | 2.5 | 2725 | 97.5 | 0.003 |
No children at home | 3486 | 55.3 | 49 | 1.4 | 3374 | 98.6 | |
Socio-economic groupb
| |||||||
Unskilled employees | 906 | 14.7 | 20 | 2.3 | 863 | 97.7 | 0.963 |
Skilled employees | 917 | 14.9 | 19 | 2.1 | 886 | 97.9 | |
Assistant non-manual employees | 732 | 11.9 | 15 | 2.1 | 716 | 97.9 | |
Intermediate non-manual employees | 1933 | 31.5 | 35 | 1.8 | 1876 | 98.2 | |
Professionals/upper-level executives | 1265 | 20.6 | 22 | 1.8 | 1229 | 98.2 | |
Self-employed | 393 | 6.4 | 8 | 2.1 | 380 | 97.9 | |
Job demands and controlb
| |||||||
High demands | 2593 | 44.7 | 59 | 2.3 | 2506 | 97.7 | 0.048 |
Low demands | 3202 | 55.3 | 50 | 1.6 | 3113 | 98.4 | |
Low control | 3227 | 55.6 | 58 | 1.8 | 3129 | 98.2 | 0.477 |
High control | 2575 | 44.4 | 53 | 2.1 | 2495 | 97.9 |
Mean | Sd | Mean | Sd | Mean | Sd | ||
---|---|---|---|---|---|---|---|
Depressive symptoms | 4.57 | 4.10 | 8.82 | 4.17 | 4.48 | 4.06 | 0.000 |
Univariate trajectory models of job demands and control
Joint trajectory model
Characteristics of the joint trajectories
Joint trajectory groups | |||||||
---|---|---|---|---|---|---|---|
Passive (1) | Passive (2) | High strain (3) | Hybrid (4) | Low strain (5) | Active (6) | Low strain (7) | |
% | % | % | % | % | % | % | |
Sex | |||||||
Men | 46.2 | 40.9 | 37.1 | 44.8 | 45.4 | 41.4 | 52.0 |
Women | 53.8 | 59.1 | 62.9 | 55.2 | 54.6 | 58.6 | 48.0 |
Age group | |||||||
< 35 years | 13.1 | 9.8 | 10.1 | 7.2 | 6.9 | 7.8 | 7.0 |
35–49 years | 27.3 | 26.0 | 25.0 | 26.1 | 24.6 | 32.1 | 27.9 |
≥ 50 years | 59.6 | 64.2 | 64.9 | 66.7 | 68.5 | 60.0 | 65.1 |
Civil status | |||||||
Single | 32.0 | 23.3 | 24.0 | 19.8 | 19.5 | 15.3 | 15.2 |
Married/cohabiting | 68.0 | 76.7 | 76.0 | 80.2 | 80.5 | 84.7 | 84.8 |
Children | |||||||
Children at home | 39.7 | 39.5 | 41.5 | 43.7 | 41.4 | 53.3 | 47.8 |
No children at home | 60.3 | 60.5 | 58.5 | 56.3 | 58.6 | 46.7 | 52.2 |
Socio-economic group | |||||||
Unskilled employees | 53.6 | 28.7 | 28.5 | 12.8 | 10.6 | 5.0 | 2.7 |
Skilled employees | 12.3 | 17.8 | 22.2 | 18.7 | 13.0 | 9.8 | 8.3 |
Assistant non-manual employees | 20.0 | 23.5 | 15.3 | 12.3 | 10.9 | 5.1 | 5.0 |
Intermediate non-manual employees | 11.8 | 19.9 | 25.7 | 33.7 | 35.6 | 40.0 | 34.3 |
Professionals/upper-level executives | 1.4 | 6.3 | 7.6 | 17.3 | 20.1 | 34.0 | 37.3 |
Self-employed | 0.9 | 3.8 | 0.7 | 5.3 | 9.8 | 6.2 | 12.4 |
Joint trajectories and the association with subsequent symptoms of major depression
Joint trajectory groups | Depression cases n (%) | Modell 1 | Modell 2 | Modell 3 | Modell 4 | |||||
---|---|---|---|---|---|---|---|---|---|---|
OR | CI | OR | CI | OR | CI | OR | CI | |||
Low strain (5 and 7) reference | 30 (1.4) | |||||||||
Passive (1) | 7 (2.6) | 1.91 | 0.83–4.39 | 1.27 | 0.54–2.97 | 1.74 | 0.75–4.04 | 1.22 | 0.52-2.90 | |
Passive (2) | 16 (1.6) | 1.18 | 0.64–2.17 | 1.09 | 0.58–2.03 | 1.14 | 0.61–2.12 | 1.07 | 0.57-2.01 | |
High strain (3) | 25 (3.3) |
2.47
| 1.45–4.24 | 1.35 | 0.78–2.37 |
2.15
| 1.24–3.74 | 1.27 | 0.72-2.24 | |
Hybrid passive/high strain (4) | 50 (2.0) | 1.47 | 0.93–2.32 | 1.12 | 0.70–1.80 | 1.43 | 0.90–2.27 | 1.13 | 0.70-1.83 | |
Active (6) | 32 (2.9) |
2.18
| 1.32–3.61 | 1.27 | 0.76–2.14 |
2.04
| 1.23–3.40 | 1.29 | 0.76-2.19 | |
Covariatesa
| ||||||||||
Previous depressive symptoms | – | – |
1.24
| 1.19–1.28 | – | – |
1.23
| 1.18–1.27 | ||
Age (continuous) | – | – | – | – |
0.97
| 0.95–0.98 |
0.97
| 0.96–0.99 | ||
Women | – | – | – | – |
1.57
| 1.12–2.20 | 1.38 | 0.97–1.95 | ||
No children at home | – | – | – | – | 0.76 | 0.54–1.07 | 0.80 | 0.57–1.12 | ||
Civil status (married/cohabiting) | – | . | – | – |
0.64
| 0.44–0.93 | 0.69 | 0.47–1.01 |