TABLE 1.
Association of risk factors with EHM development.
| Risk factor | Categories/Units | Non‐EHM | EHM | OR (95% CI) | p | |
|---|---|---|---|---|---|---|
| Age | Years | Mean (SD) | 9.8 (3.4) | 9.8 (2.5) | 1.00 (0.91;1.10) | 0.98 |
| Median [P25th, P75th] | 9 [7;11] | 9 [8;11] | ||||
| N (Range) | 100 (5–21) | 89 (5–16) | ||||
| < 7y | 34 (34%) | 14 (15.73%) | [Ref] | |||
| 8–9 y | 20 (20%) | 31 (34.83%) | 3.76 (1.63; 8.71) | 0.00 | ||
| 10–11y | 16 (16%) | 24 (26.97%) | 3.64 (1.50; 8.85) | 0.00 | ||
| > 11 y | 30 (30%) | 20 (22.47%) | 1.62 (0.70; 3.75) | 0.26 | ||
| Sex | Stallion | N (%) | 16 (15.69%) | 11 (12.36%) | [Ref] | |
| Mare | N (%) | 41 (40.20%) | 43 (48.31%) | 1.53 (0.63; 3.67) | 0.34 | |
| Gelding | N (%) | 45 (44.12%) | 35 (39.33%) | 1.13 (0.47; 2.74) | 0.78 | |
| Mare vs other | N (%) | 1.39 (0.78; 2.47) | 0.2 | |||
| Vaccination | No | N (%) | 77 (84.62%) | 46 (54.76%) | ||
| Yes | N (%) | 14 (15.38%) | 38 (45.24%) | 4.54 (2.23; 9.27) | < 0.001 | |
| Vaccination adjusted by age (categorical) | 4.06 (1.94; 8.51) | < 0.001 | ||||
| Vaccination adjusted by sex | 4.41 (2.15; 9.05) | < 0.001 | ||||
| Vaccination adjusted by breed | 4.69 (2.18;10.09) | < 0.001 | ||||
| Vaccination adjusted by country | 3.99 (1.73–9.19) | 0.001 | ||||
| Fever | No | N (%) | 51 (50%) | 0 (0%) | ||
| Yes | N (%) | 51 (50%) | 89 (100%) | NE | < 0.001 | |
| Maximal Temperature | °C | Mean (SD) | 38.0 (0.60) | 38.4 (0.75) | 2.49 (1.34; 4.65) | 0.00 |
| Median [P25th, P75th] | 37.80 [37.70; 37.70] | 38.25 [37.85; 37.85] | ||||
| N (Range) | 45 (37.1–40.0) | 76 (36.0–40.0) | ||||
Abbreviations: NE, Not Evaluated Because of Zero Values in Cells; [Ref], Reference Category.