Table 4.
Intake of Selected Minerals From Supplemental Sources and Risk of Premenstrual Syndrome, Nurses' Health Study II Premenstrual Syndrome Substudy 1991–2001
| Mineral and Tertile | Range, mg/day | Supplement Mediana | Total Medianb | No. of Cases | No. of Controls | Age-adjusted |
Multivariablec |
||
|---|---|---|---|---|---|---|---|---|---|
| RR | 95% CI | RR | 95% CI | ||||||
| Nonheme iron | |||||||||
| Nonusers | 13.1 | 705 | 1,350 | 1.00 | Referent | 1.00 | Referent | ||
| 1 (low) | 0.4–15.4 | 10.0 | 22.0 | 122 | 202 | 1.15 | 0.90, 1.46 | 1.07 | 0.80, 1.43 |
| 2 | 15.5–30.0 | 18.0 | 34.1 | 115 | 207 | 1.04 | 0.82, 1.34 | 1.04 | 0.76, 1.42 |
| 3 | 30.1–240 | 60.0 | 74.5 | 115 | 209 | 0.99 | 0.77, 1.26 | 0.80 | 0.58, 1.10 |
| P for trendd | 0.36 | 0.19 | |||||||
| Magnesium | |||||||||
| Nonusers | 298 | 806 | 1,594 | 1.00 | Referent | 1.00 | Referent | ||
| 1 (low) | 1–57 | 14 | 331 | 93 | 116 | 1.56 | 1.17, 2.08 | 1.64 | 1.17, 2.29 |
| 2 | 58–100 | 57 | 364 | 58 | 93 | 1.22 | 0.87, 1.71 | 1.02 | 0.69, 1.51 |
| 3 | 101–480 | 100 | 421 | 100 | 165 | 1.15 | 0.89, 1.50 | 1.30 | 0.93, 1.81 |
| P for trendd | 0.12 | 0.67 | |||||||
| Manganese | |||||||||
| Nonusers | 3.3 | 870 | 1,672 | 1.00 | Referent | 1.00 | Referent | ||
| 1 (low) | 0.1–1.4 | 0.7 | 4.1 | 68 | 100 | 1.32 | 0.96, 1.81 | 1.30 | 0.90, 1.87 |
| 2 | 1.5–2.5 | 2.5 | 5.7 | 78 | 116 | 1.25 | 0.93, 1.69 | 1.41 | 0.98, 2.01 |
| 3 | 2.6–16.7 | 5.0 | 8.1 | 41 | 80 | 0.98 | 0.66, 1.44 | 0.90 | 0.57, 1.42 |
| P for trendd | 0.19 | 0.36 | |||||||
| Zinc | |||||||||
| Nonusers | 11.3 | 755 | 1,477 | 1.00 | Referent | 1.00 | Referent | ||
| 1 (low) | 0.1–8.6 | 4.3 | 16.8 | 106 | 153 | 1.34 | 1.03, 1.74 | 1.34 | 1.00, 1.84 |
| 2 | 8.7–15.0 | 15 | 26.1 | 126 | 190 | 1.24 | 0.97, 1.58 | 1.25 | 0.91, 1.72 |
| 3 | 15.1–150 | 25 | 37.7 | 70 | 148 | 0.88 | 0.65, 1.19 | 0.69 | 0.46, 1.02 |
| P for trendd | 0.03 | 0.05 | |||||||
| Copper | |||||||||
| Nonusers | 1.2 | 827 | 1,594 | 1.00 | Referent | 1.00 | Referent | ||
| 1 (low) | 0.03–1.10 | 0.3 | 1.7 | 79 | 110 | 1.37 | 1.01, 1.85 | 1.39 | 0.99, 1.97 |
| 2 | 1.2–1.9 | 1.2 | 2.9 | 43 | 73 | 1.09 | 0.74, 1.61 | 1.01 | 0.64, 1.58 |
| 3 | 2.0–6.0 | 2.0 | 3.2 | 108 | 191 | 1.03 | 0.80, 1.33 | 0.97 | 0.70, 1.35 |
| P for trendd | 0.15 | 0.50 | |||||||
Abbreviations: CI, confidence interval; RR, relative risk.
a Median intake (mg/day) of nutrient from supplemental sources only among category members.
b Median intake (mg/day) of nutrient from food and supplemental sources combined among category members.
c Adjusted for age (<30, 30–34, 35–39, or ≥40 years), year of diagnosis (1993, 1994–1995, 1996–1996, 1998–1999, or 2000–2001), number of full-term pregnancies (0, 1–2, 3–4, or ≥5 pregnancies lasting ≥6 months), body mass index (weight (kg)/height (m)2) (<20.0, 20.0–22.4, 22.5–24.9, 25.0–27.4, 27.5–29.9, or ≥30.0), pack-years of smoking (quintiles), tubal ligation (no vs. yes), duration or oral contraceptive use (0, 1–23, 24–71, 72–119 or ≥120 months), antidepressant use (never vs. ever), history of childhood trauma score (5, 6–10, 11–15, or ≥16), and intakes of alcohol, vitamin B6, calcium, and vitamin D (quintiles). Intake of each mineral from supplements is adjusted for intake of the respective mineral from food sources only.
d Test for trend among users of supplements only.