Table 3.
Cox proportional HR with 95% CI for the association between childbirth, hospitalisation and new sickness absence (SA) in year 3–5 after T0, in twins where at least one in the pair had their first childbirth during 1994–2009
| Status childbirth and hospitalisation | SA in year 3–5 after T0 (regardless of the number of days) |
Long-term SA (>90 days) in year 3–5 after T0 |
||||||
|---|---|---|---|---|---|---|---|---|
| Model a* | Model b† | Model c‡ | Discordant twin pairs§, ‡ | Model a* | Model b† | Model c‡ | Discordant twin pairs¶, ‡ | |
| All women (n=5118) | ||||||||
| No childbirth, no hospitalisation year 1–2 after T0** | 1 (REF) | 1 (REF) | 1 (REF) | 1 (REF) | 1 (REF) | 1 (REF) | 1 (REF) | 1 (REF) |
| No childbirth, hospitalisation year 1–2 after T0** | 2.7 (1.8 to 4.1) | 2.2 (1.5 to 3.4) | 2.1 (1.4 to 3.2) | 1.5 (0.8 to 2.9) | 4.5 (2.5 to 8.2) | 3.5 (1.9 to 6.2) | 2.8 (1.5 to 5.1) | 1.1 (0.5 to 2.3) |
| Childbirth, no hospitalisation year 1–2 after T0** | 2.1 (1.8 to 2.5) | 1.8 (1.5 to 2.2) | 1.8 (1.5 to 2.2) | 1.7 (1.3 to 2.2) | 1.1 (0.8 to 1.6) | 1.0 (0.7 to 1.4) | 1.0 (0.7 to 1.3) | 0.8 (0.6 to 1.2) |
| Childbirth, hospitalisation year 1–2 after T0** | 3.0 (2.5 to 3.6) | 2.4 (2.0 to 2.9) | 2.4 (2.0 to 2.9) | 2.0 (1.5 to 2.6) | 2.3 (1.6 to 3.2) | 1.8 (1.3 to 2.5) | 1.8 (1.3 to 2.5) | 1.0 (0.7 to 1.5) |
| Women who had at least one childbirth (n=2792) | Model a* | Model b† | Model c‡ | Discordant twin pairs††,* | Model a* | Model b† | Model c‡ | Discordant twin pairs‡‡, ‡ |
| No hospitalisation year 1–2 after T0** | 1 (REF) | 1 (REF) | 1 (REF) | 1 (REF) | 1 (REF) | 1 (REF) | 1 (REF) | 1 (REF) |
| Hospitalisation year 1–2 after T0** | 1.3 (1.2 to 1.5) | 1.3 (1.1 to 1.4) | 1.2 (1.1 to 1.4) | 1.2 (1.0 to 1.5) | 2.0 (1.5 to 2.6) | 1.9 (1.4 to 2.5) | 1.8 (1.4 to 2.4) | 1.4 (1.0 to 1.9) |
Three models for adjustments as well as for discordant twin pairs.
*Adjusted for birth year.
†Model a, and additional adjustments for delivery year and educational level.
‡Model b, and additional adjustments for earlier hospitalisation.
§Twin pairs where one had an SA during the follow-up and the other did not (n=835 pairs).
¶Twin pairs where one had a long-term SA during the follow-up and the other did not (n=277 pairs).
**Diagnoses O00-O99 excluded.
††Twin pairs where one had an SA during the follow-up and the other did not (n=542 pairs).
‡‡Twin pairs where one had a long-term SA during the follow-up and the other did not (n=184 pairs).