Table 6 Cox regression analyses showing relevance of proxies for genetics vs environmental risk factors
|  |  | Univariate Cox regression analyses N = sample sizes a, b, c, d in respective analysis | Multivariate Cox regression analyses N = 27 458 of which 141 with outcome |
|---|---|---|---|
| Â | Â | HR (95%CI) | HR (95%CI) |
Zygosity a | Â | Â | |
| Â | DZ twins | 1 (ref) | NA |
|  | MZ twins | 1.62 (1.17–2.25) | NA |
Sex a | Â | Â | |
| Â | Opposite sex DZ twins | 1 (ref) | 1 (ref) |
|  | Same sex MZ twins, male | 2.50 (1.52–4.13) | 3.64 (2.14–6.19) |
|  | Same sex MZ twins, female | 1.69 (1.01–2.82) | 2.34 (1.34–4.07) |
|  | Same sex DZ twins, male | 1.64 (0.97–2.79) | 2.05 (1.18–3.55) |
|  | Same sex DZ twins, female | 1.30 (0.76–2.22) | 1.40 (0.79–2.49) |
Age (always shared) a | 1.11 (1.10–1.13) | 1.11 (1.10–1.13) | |
College/university (>1 years) a | Â | Â | |
| Â | Both twins high education | 1 (ref) | 1 (ref) |
|  | One twin high, one twin low education | 1.34 (0.71–2.52) | 0.95 (0.50–1.79) |
|  | Both twins low education | 2.44 (1.44–4.12) | 0.89 (0.52–1.52) |
Overweight, ≥25 kg/m2 b | |||
| Â | None of twins overweight | 1 (ref) | 1 (ref) |
|  | One twin overweight, one twin normal weight | 1.43 (0.93–2.21) | 1.40 (0.90–2.19) |
|  | Both twins overweight | 4.21 (2.88–6.17) | 3.44 (2.31–5.12) |
Ever regular smoker c | |||
| Â | None of twins smokers | 1 (ref) | 1 (ref) |
|  | One twin smoker, one twin non-smoker | 1.20 (0.80–1.80) | 1.77 (1.16–2.71) |
|  | Both twins smokers | 0.75 (0.50–1.14) | 1.37 (0.88–2.12) |
Physically active d | |||
| Â | Both twins physically active | 1 (ref) | Omitted due to missing data |
|  | One twin physically ative, one twin physically inactive | 1.08 (0.62–1.86) |  |
|  | Both twins physically inactive | 1.06 (0.63–1.78) |  |
