Table 5 Descriptive characteristics showing degree of shared observed environmental factors, pair level
| Â | Â | All MZ pairs | MZ Pairs where both twins have both OA and severe CVD | All DZ pairs | DZ Pairs where both twins have both OA and severe CVD |
|---|---|---|---|---|---|
|  |  | N = 9475 | N = 64 | N = 20 510 | N = 81 |
Age at start of follow-up, mean (SD) | 46 (17) | 60 (9) | 49 (16) | 61 (10) | |
Same sex, M, n (%) | 4128 (44) | 34 (53) | 5400 (26) | 27 (33) | |
Same sex, F, n (%) | 5347 (56) | 30 (47) | 6617 (32) | 26 (32) | |
Opposite sex, n (%) | 0 | 0 | 8493 (41) | 28 (35) | |
College/university (>1 years), n (%) | Â | Â | |||
| Â | Both twins high education | 2258 (24) | 10 (16) | 3069 (15) | 6 (7) |
| Â | One twin high, one twin low education | 1474 (16) | 6 (9) | 4835 (24) | 18 (22) |
| Â | Both twins low education | 5743 (61) | 48 (75) | 12,606 (61) | 57 (70) |
Overweight, ≥25 kg/m2, n (%) | |||||
| Â | None of twins overweight | 5799 (62) | 26 (41) | 9336 (46) | 24 (30) |
| Â | One twin overweight, one twin normal weight | 1543 (16) | 13 (20) | 6376 (31) | 22 (27) |
| Â | Both twins overweight | 1478 (16) | 25 (39) | 3040 (15) | 31 (38) |
Ever regular smoker, n (%) | |||||
| Â | None of twins smokers | 2931 (31) | 21 (33) | 5253 (26) | 20 (25) |
| Â | One twin smoker, one twin non-smoker | 1906 (20) | 17 (27) | 6612 (32) | 37 (46) |
| Â | Both twins smokers | 4291 (45) | 26 (41) | 7795 (38) | 24 (30) |
Physical inactivity, n (%) | |||||
| Â | Both twins physically active | 2017 (22) | 13 (22) | 2214 (16) | 9 (17) |
| Â | One twin physically ative, one twin physically inactive | 2051 (23) | 17 (28) | 4005 (30) | 14 (26) |
| Â | Both twins physically inactive | 3737 (42) | 21 (35) | 5103 (38) | 19 (35) |
