Table 2.
Serum 25(OH)D and fibroid growth, 434a participants from the Study of Environment, Lifestyle & Fibroids, Detroit, Michigan, 2010–2018
| Categories of 25(OH)D ng/ml | No. growth intervals | Estimated % difference in growth (95% CI) | |
|---|---|---|---|
| Minimally Adjustedb | Fully Adjustedc | ||
| <12 | 394 | REF | REF |
| 12–<20 | 524 | 2.8 (−7.1, 13.7) | 4.7 (−5.0, 15.4) |
| 20–<30 | 321 | −6.6 (−16.9, 5.0) | −6.3 (−16.4, 5.0) |
| ≥30 | 118 | −7.7 (−21.9, 9.1) | −9.1 (−22.6, 6.8) |
| <20 | 918 | REF | REF |
| ≥20 | 439 | −8.4 (−16.4, 0.3) | −9.7 (−17.3, −1.3) |
| <30 | 1239 | REF | REF |
| ≥30 | 118 | −6.5 (−19.6, 8.7) | −8.8 (−21.0, 5.4) |
Note: 25(OH)D = 25-hydroxyvitamin D; CI = confidence interval.
Growth analyses were conducted among fibroids which could be matched across successive visits based on fibroid location. This includes fibroids from 434 participants with 1357 interval growth measurements. Participants could contribute multiple fibroids and fibroids could be followed across multiple intervals.
Minimally adjusted model includes volume of fibroid (<0.5 cm3, 0.5–4.19 cm3, 4.2–14.0 cm3, ≥14.1 cm3), number of fibroids (ordinal 1, 2, 3, ≥4), age (continuous).
Fully adjusted models further adjust for years since last birth (<5 years, ≥5 years ago including no birth), years since last use of injection contraceptive (<2 years, ≥2 years/never), body mass index kg/m2 (<25, 25–<30, 30–<35, 35–<40, ≥40), income (<$20,000, $20–50,000, >$50,000), employment (employed yes/no), age at menarche (ordinal <11, 11, 12, 13, >13 years). Three observations excluded from analyses due to missing data on at least one covariate.