Relative rates of haemorrhagic and ischaemic stroke and 95% confidence intervals by number of siblings in 5765 men aged 35–64 from the Collaborative study in 25 years of follow up. Stroke defined as either stroke hospital admission or death
| Siblings | ||||||
|---|---|---|---|---|---|---|
| 0–2* | 3 or 4 | 5 or 6 | 7 or more | Relative rate per sibling | Trend† | |
| *Baseline category. †Using siblings as a continuous variable. ‡Adjusted for age. §Adjusted for age, smoking, social class, father’s social class, car user, deprivation category, education, bronchitis, height, adjusted FEV1, systolic blood pressure, cholesterol, and units of alcohol. | ||||||
| Number of participants | 2532 | 1535 | 915 | 783 | ||
| All stroke | ||||||
| Number of strokes | 161 | 105 | 77 | 73 | ||
| Relative rate‡ (95% CI) | 1 | 0.99 (0.77 to 1.27) | 1.17 (0.89 to 1.53) | 1.34 (1.02 to 1.78) | 1.05 (1.01 to 1.09) | 0.010 |
| Relative rate§ (95% CI) | 1 | 0.88 (0.68 to 1.13) | 0.97 (0.73 to 1.29) | 1.07 (0.80 to 1.44) | 1.02 (0.98 to 1.06) | 0.36 |
| Haemorrhagic | ||||||
| Number of strokes | 14 | 14 | 9 | 10 | ||
| Relative rate‡ (95% CI) | 1 | 1.63 (0.77 to 3.42) | 1.74 (0.75 to 4.05) | 2.33 (1.02 to 5.29) | 1.11 (1.01 to 1.23) | 0.031 |
| Relative rate§ (95% CI) | 1 | 1.60 (0.74 to 3.45) | 1.74 (0.71 to 4.24) | 2.29 (0.95 to 5.53) | 1.11 (1.00 to 1.23) | 0.058 |
| Ischaemic | ||||||
| Number of strokes | 43 | 23 | 16 | 18 | ||
| Relative rate‡ (95% CI) | 1 | 0.86 (0.52 to 1.44) | 1.00 (0.56 to 1.78) | 1.36 (0.78 to 2.37) | 1.03 (0.96 to 1.11) | 0.45 |
| Relative rate§ (95% CI) | 1 | 0.81 (0.48 to 1.37) | 0.88 (0.48 to 1.61) | 1.18 (0.66 to 2.14) | 1.01 (0.93 to 1.09) | 0.81 |