Table 4.
Mediation analysis for the association between pain Type, number of pain sites, and all-cause mortality.
| Mediators |
Pain type |
|||
|---|---|---|---|---|
| Neck or shoulder pain only | Back pain only | Hip pain only | Knee pain only | |
| Total associationa | 1.08 (1.05, 1.12) | 1.17 (1.11, 1.22) | 1.16 (1.08, 1.24) | 1.03 (0.98, 1.07) |
| Opioid useb | ||||
| Natural direct association | 1.03 (0.97, 1.06) | 1.08 (1.03, 1.12) | 1.09 (0.99, 1.15) | 0.98 (0.94, 1.03) |
| Natural indirect association | 1.03 (1.02, 1.05) | 1.07 (1.05, 1.09) | 1.05 (1.03, 1.08) | 1.03 (1.02, 1.04) |
| Proportion mediated,% | 42.6 | 45.2 | 34.9 | 78.9 |
| Smoking statusc | ||||
| Natural direct association | 1.06 (1.01, 1.10) | 1.13 (1.06, 1.18) | 1.12 (1.05, 1.21) | 1.03 (0.98, 1.06) |
| Natural indirect association | 1.02 (1.02, 1.03) | 1.04 (1.03, 1.04) | 1.03 (1.02, 1.04) | 1.01 (1.00, 1.01) |
| Proportion mediated,% | 29.8 | 23.9 | 23.3 | 19.0 |
| Alcohol consumptiond | ||||
| Natural direct association | 1.07 (1.01, 1.12) | 1.15 (1.11, 1.23) | 1.15 (1.09, 1.24) | 1.03 (0.98, 1.06) |
| Natural indirect association | 1.01 (1.01, 1.02) | 1.01 (1.01, 1.01) | 1.00 (1.00, 1.01) | 1.00 (1.00, 1.01) |
| Proportion mediated,% | 17.5 | 8.2 | 2.4 | 15.4 |
| Physical activitye | ||||
| Natural direct association | 1.08 (1.06, 1.11) | 1.15 (1.10, 1.21) | 1.13 (1.03, 1.21) | 1.03 (0.98, 1.08) |
| Natural indirect association | 1.01 (1.01, 1.01) | 1.01 (1.01, 1.02) | 1.01 (1.00, 1.02) | 1.00 (1.00, 1.00) |
| Proportion mediated,% | 9.3 | 9.1 | 8.0 | 9.8 |
| Lifestyle behaviours (smoking status, alcohol consumption, and physical activity) | ||||
| Natural direct association | 1.05 (1.02, 1.08) | 1.11 (1.05, 1.17) | 1.10 (1.01, 1.19) | 1.02 (0.97, 1.05) |
| Natural indirect association | 1.03 (1.03, 1.04) | 1.06 (1.05, 1.07) | 1.04 (1.03, 1.05) | 1.01 (1.01, 1.02) |
| Proportion mediated,% | 41.0 | 38.0 | 30.5 | 41.8 |
| All four | ||||
| Natural direct association | 0.99 (0.97, 1.04) | 1.04 (0.99, 1.08) | 1.05 (0.97, 1.11) | 0.97 (0.92, 1.02) |
| Natural indirect association | 1.07 (1.06, 1.08) | 1.12 (1.11, 1.15) | 1.09 (1.07, 1.12) | 1.04 (1.03, 1.05) |
| Proportion mediated,% | 86.8 | 74.1 | 65.1 | 122.6 |
| Number of pain sites | ||||
| One | Two | Three | Four | |
| Total association | 1.09 (1.06, 1.12) | 1.25 (1.21, 1.30) | 1.43 (1.36, 1.51) | 1.46 (1.35, 1.57) |
| Opioid use | ||||
| Natural direct association | 1.03 (1.01, 1.06) | 1.17 (1.14, 1.21) | 1.30 (1.22, 1.36) | 1.11 (1.03, 1.20) |
| Natural indirect association | 1.04 (1.03, 1.05) | 1.08 (1.07, 1.10) | 1.11 (1.08, 1.14) | 1.32 (1.24, 1.41) |
| Proportion mediated,% | 47.0 | 34.9 | 32.5 | 45.2 |
| Smoking status | ||||
| Natural direct association | 1.07 (1.04, 1.11) | 1.22 (1.18, 1.27) | 1.38 (1.31, 1.46) | 1.38 (1.29, 1.48) |
| Natural indirect association | 1.02 (1.02, 1.03) | 1.04 (1.03, 1.04) | 1.05 (1.04, 1.06) | 1.08 (1.06, 1.11) |
| Proportion mediated,% | 24.7 | 17.1 | 14.6 | 22.2 |
| Alcohol consumption | ||||
| Natural direct association | 1.08 (1.06, 1.11) | 1.23 (1.19, 1.26) | 1.39 (1.35, 1.47) | 1.40 (1.29, 1.48) |
| Natural indirect association | 1.01 (1.01, 1.01) | 1.02 (1.01, 1.02) | 1.04 (1.03, 1.06) | 1.04 (1.01, 1.08) |
| Proportion mediated,% | 10.5 | 8.7 | 13.0 | 12.7 |
| Physical activity | ||||
| Natural direct association | 1.08 (1.06, 1.11) | 1.23 (1.18, 1.27) | 1.39 (1.32, 1.46) | 1.40 (1.30, 1.52) |
| Natural indirect association | 1.01 (1.01, 1.01) | 1.01 (1.01, 1.02) | 1.04 (1.03, 1.04) | 1.05 (1.03, 1.08) |
| Proportion mediated,% | 9.1 | 9.8 | 11.8 | 15.7 |
| Lifestyle behaviours (smoking status, alcohol consumption, and physical activity) | ||||
| Natural direct association | 1.06 (1.03, 1.09) | 1.18 (1.14, 1.22) | 1.31 (1.27, 1.36) | 1.28 (1.20, 1.38) |
| Natural indirect association | 1.04 (1.03, 1.04) | 1.07 (1.06, 1.08) | 1.12 (1.10, 1.13) | 1.17 (1.13, 1.20) |
| Proportion mediated,% | 39.7 | 31.1 | 34.2 | 42.8 |
| All four | ||||
| Natural direct association | 1.01 (0.97, 1.04) | 1.07 (1.01, 1.11) | 1.10 (1.03, 1.17) | 1.00 (0.92, 1.10) |
| Natural indirect association | 1.07 (1.06, 1.08) | 1.13 (1.11, 1.14) | 1.20 (1.16, 1.23) | 1.30 (1.23, 1.39) |
| Proportion mediated,% | 73.7 | 54.1 | 53.4 | 69.6 |
Data are presented as hazard ratio (95% confidence interval) unless otherwise indicated. Effect estimates with statistical significance are labelled in bold.
a
The effect estimate with its 95% confidence interval was slightly different for each mediation analysis. To reduce overlap, we listed the value from Tables 2 and 3.
b
The mediator of opioid use was modelled as yes vs no.
c
The mediator of smoking status was modelled as current smoking vs never or previous smoking.
d
The mediator of alcohol consumption was modelled as regular vs special occasions or never.
e
The mediator of physical activity was modelled as low vs moderate or high.