Table 2.
Cox proportional hazard ratios (HR) with 95% confidence intervals (CI) of background factors, occupational groups, psychosocial working conditions and job strain for being granted DP due to MSD during the follow-up
| |
Age- and sex-adjusted1 |
|
|
Discordant twin pairs2 |
|
|
|---|---|---|---|---|---|---|
| |
|
MZ (n = 427 pairs) |
|
DZ (n = 745 pairs) |
|
|
| HR | 95% CI | HR | 95% CI | HR | 95% CI | |
|
Sex (being a woman) |
1.73 |
1.57, 1.91 |
- |
- |
- |
- |
|
Marital status (unmarried) |
1.15 |
1.05, 1.27 |
1.01 |
0.83, 1.24 |
1.07 |
0.91, 1.25 |
|
Children living at home (no) |
1.32 |
1.19, 1.45 |
0.97 |
0.79, 1.21 |
1.41 |
1.20, 1.67 |
|
Education (number of years) |
0.82 |
0.80, 0.84 |
0.94 |
0.88, 1.01 |
0.84 |
0.81, 0.88 |
|
Type of living area (semi-rural/rural) |
1.34 |
1.21, 1.47 |
1.00 |
0.75, 1.33 |
1.41 |
1.12, 1.76 |
|
Occupational groups defined by sector |
|
|
|
|
|
|
| Administration& management |
1.00 |
referent |
1.00 |
referent |
1.00 |
referent |
| Technology, science, social science& art |
0.95 |
0.76, 1.18 |
1.27 |
0.76, 2.13 |
1.33 |
0.93, 1.88 |
| Health care& social work |
2.06 |
1.72, 2.46 |
1.61 |
1.05, 2.48 |
1.94 |
1.44, 2.66 |
| Commercial work |
1.54 |
1.21, 1.95 |
1.03 |
0.62, 1.72 |
1.46 |
1.01, 2.10 |
| Agriculture, forestry& fishing |
2.33 |
1.74, 3.14 |
2.01 |
0.94, 4.30 |
2.37 |
1.41, 3.98 |
| Transport |
2.88 |
2.27, 3.66 |
2.68 |
1.35, 5.33 |
3.16 |
2.04, 4.89 |
| Production& mining |
3.51 |
2.92, 4.21 |
1.88 |
1.15, 3.08 |
2.83 |
2.03, 3.94 |
| Service& military work |
2.90 |
2.40, 3.51 |
1.48 |
0.91, 2.43 |
2.71 |
1.94, 3.78 |
|
Psychosocial working conditions |
|
|
|
|
|
|
| Job demands (range 1–10, high score is low) |
1.63 |
1.54, 1.73 |
1.17 |
1.00, 1.37 |
1.35 |
1.20, 1.53 |
| Job control (range 1–10, high score is high) |
0.76 |
0.73, 0.78 |
0.80 |
0.72, 0.89 |
0.79 |
0.74, 0.85 |
| Social support (range 1–10, high score is high) |
1.17 |
1.05, 1.30 |
0.90 |
0.75, 1.09 |
0.94 |
0.81, 1.10 |
|
Job strain |
|
|
|
|
|
|
| High strain |
0.75 |
0.59, 0.96 |
1.87 |
1.07, 3.29 |
0.81 |
0.55, 1.21 |
| Low strain |
1.00 |
referent |
1.00 |
referent |
1.00 |
referent |
| Active |
0.60 |
0.51, 0.71 |
1.06 |
0.76, 1.50 |
0.79 |
0.60, 1.03 |
| Passive |
1.54 |
1.33, 1.80 |
1.41 |
1.03, 1.94 |
1.35 |
1.04, 1.75 |
| Iso-strain | 1.15 | 0.93, 1.41 | 2.84 | 1.58, 5.11 | 1.43 | 1.00, 2.03 |
Notes: 1 Clustered on pair identity, 2MZ=monozygotic, DZ=dizygotic.