Table 3.
Difference in Rate of Stress Fractures and Stress Reactions Among College Athletes, 2012 to 2018, by Vitamin D Levels (Low in Vitamin D, Improved Vitamin D, or Normal Vitamin D)
| Male and Female Athletes Combined | Stress Fractures | Stress Reactions and Stress Fractures | ||||
|---|---|---|---|---|---|---|
| n (%) | % Difference (95% CI) | P Value | n (%) | % Difference (95% CI) | P Value | |
| “Stayed low” vs “low at baseline but improved” | ||||||
| <40 and improved to ≥40 ng/mL (n = 328) | 2 (0.6) | Reference | 21 (6.4) | Reference | ||
| <40 and stayed <40 ng/mL (n = 100) | 13 (13.0) | 12 (6-19) | <.001 | 25 (25.0) | 19 (10-27) | <.001 |
| “Stayed low” vs “maintained normal levels” | ||||||
| Maintained vitamin D ≥40 ng/mL (n = 366) | 5 (1.4) | Reference | 23 (6.3) | Reference | ||
| <40 and stayed <40 ng/mL (n = 100) | 13 (13.0) | 12 (5-18) | <.001 | 25 (25.0) | 19 (10-28) | <.001 |
| “Low at baseline but improved” vs “maintained normal levels” | ||||||
| Maintained vitamin D ≥40 ng/mL (n = 366) | 5 (1.4) | Reference | 23 (6.3) | Reference | ||
| <40 and improved to ≥40 ng/mL (n = 328) | 2 (0.6) | –0.76 (–2.2 to 0.7) | .32 | 21 (6.4) | 0.1 (–4 to 4) | .95 |