Table 4.
Associations between mortality and zygosity in individual twins, birth cohorts 1961–1990, surviving to age 6; among individual twins at ages up to 50 years, and from 50 years.
| All Ages, n = 39,504 |
Ages ≤50, n = 39,504 |
Ages >50, n = 8711 |
|
|---|---|---|---|
| Both sexes a | HR (95%-CI) | HR (95%-CI) | HR (95%-CI) |
| Zygosity | |||
| MZ | Ref. | Ref. | Ref. |
| SSDZ | 1.07 (0.89, 1.13) | 1.10 (0.91, 1.34) | 0.80 (0.46, 1.40) |
| OSDZ | 1.21 (1.01, 1.45) * | 1.23 (1.02, 1.48) * | 1.05 (0.61, 1.79) |
| UZ | 1.83 (1.47, 2.28) *** | 1.89 (1.51, 2.37) *** | 1.25 (0.49, 3.20) |
| Males | |||
| Zygosity | |||
| MZ | Ref. | Ref. | Ref. |
| SSDZ | 1.01 (0.80, 1.28) | 1.06 (0.83, 1.35) | 0.63 (0.29, 1.37) |
| OSDZ | 1.22 (0.97, 1.53) | 1.23 (0.97, 1.55) | 1.14 (0.56, 2.29) |
| UZ | 1.86 (1.43, 2.42) *** | 1.92 (1.46, 2.51) *** | 1.26 (0.39, 4.11) |
| Females | |||
| Zygosity | |||
| MZ | Ref. | Ref. | Ref. |
| SSDZ | 1.17 (0.88, 1.56) | 1.19 (0.88, 1.62) | 1.04 (0.46, 2.31) |
| OSDZ | 1.19 (0.90, 1.58) | 1.23 (0.91, 1.67) | 1.14 (0.56, 2.28) |
| UZ | 1.71 (1.13, 2.60) * | 1.78 (1.15, 2.75) ** | 1.18 (0.26, 5.45) |
a Baseline hazard stratified on sex. * p < 0.05, ** p < 0.01, *** p < 0.001.