Table 3.
Hazard ratios and 95% confidence intervals for association between incident gout and various reproductive factors in women stratified by body mass index
| Body mass index (kg/m2) | p for interaction | |||||
|---|---|---|---|---|---|---|
| < 18.5 | 18.5–23 | 23–25 | 25–30 | ≥30 | ||
| Age at menarche (years) | 0.0033 | |||||
| ≤ 12 | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | |
| 13–14 | 1.04 (0.48–2.25) | 1.01 (0.87–1.16) | 1.30 (1.09–1.55) | 1.01 (0.88–1.14) | 0.92 (0.69–1.22) | |
| 15–16 | 1.39 (0.66–2.95) | 1.08 (0.93–1.24) | 1.30 (1.09–1.54) | 0.96 (0.85–1.09) | 0.91 (0.69–1.20) | |
| > 16 | 1.38 (0.65–2.93) | 1.11 (0.96–1.28) | 1.34 (1.13–1.60) | 1.00 (0.88–1.13) | 0.94 (0.71–1.24) | |
| Age at menopause (years) | 0.6741 | |||||
| < 40 | 1.31 (0.82–2.07) | 1.20 (1.07–1.34) | 1.05 (0.92–1.20) | 1.10 (0.99–1.21) | 1.17 (0.95–1.43) | |
| 40–44 | 1.29 (1.00–1.68) | 1.04 (0.97–1.11) | 1.06 (0.99–1.14) | 1.09 (1.03–1.16) | 0.94 (0.83–1.08) | |
| 45–49 | 0.98 (0.83–1.15) | 1.03 (1.00–1.07) | 1.03 (0.99–1.06) | 1.02 (0.99–1.06) | 1.01 (0.94–1.09) | |
| 50–54 | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | |
| ≥ 55 | 0.97 (0.73–1.29) | 0.98 (0.93–1.03) | 0.98 (0.93–1.03) | 0.95 (0.92–0.99) | 0.95 (0.86–1.04) | |
| Reproductive span | 0.5289 | |||||
| < 30 | 1.08 (0.75, 1.55) | 1.10 (1.02, 1.18) | 1.07 (0.99, 1.15) | 1.13 (1.06, 1.19) | 1.05 (0.92, 1.19) | |
| 30–34 | 0.95 (0.68, 1.33) | 1.07 (1.00, 1.14) | 1.04 (0.97,1.10) | 1.06 (1.01, 1.11) | 1.07 (0.95, 1.20) | |
| 35–39 | 0.82 (0.58, 1.15) | 1.03 (0.96, 1.10) | 0.99 (0.93, 1.05) | 1.04 (0.99, 1.10) | 1.01 (0.90, 1.13) | |
| ≥ 40 | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | |
| Oral contraceptives (years) | 0.1990 | |||||
| Never | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | |
| < 1 | 1.12 (0.88–1.43) | 1.04 (0.99–1.09) | 1.01 (0.96–1.06) | 1.04 (1.00–1.08) | 1.00 (0.91–1.11) | |
| ≥ 1 | 1.13 (0.83–1.54) | 1.12 (1.06–1.18) | 1.04 (0.98–1.10) | 1.01 (0.96–1.06) | 1.05 (0.94–1.18) | |
| Hormone replacement therapy (years) | 0.4493 | |||||
| Never | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | |
| < 2 | 1.22 (0.99–1.52) | 1.19 (1.14–1.24) | 1.16 (1.10–1.21) | 1.13 (1.09–1.18) | 1.11 (0.99–1.24) | |
| 2–5 | 0.91 (0.63–1.31) | 1.17 (1.10–1.24) | 1.19 (1.11–1.28) | 1.15 (1.08–1.23) | 1.11 (0.91–1.35) | |
| ≥ 5 | 1.01 (0.67–1.53) | 1.21 (1.13–1.30) | 1.21 (1.12–1.31) | 1.15 (1.07–1.24) | 1.16 (0.89–1.40) | |
| Parity | 0.9025 | |||||
| 0 children | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | |
| 1 child | 1.36 (0.88–1.96) | 0.98 (0.89–1.09) | 1.03 (0.91–1.15) | 0.98 (0.88–1.08) | 0.94 (0.73–1.21) | |
| ≥ 2 children | 1.11 (0.76–1.64) | 0.96 (0.87–1.05) | 1.02 (0.92–1.13) | 0.99 (0.91–1.09) | 1.00 (0.80–1.26) | |
| Breastfeeding (months) | 0.6125 | |||||
| Never | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | 1 (Ref.) | |
| < 6 | 0.84 (0.62–1.14) | 1.00 (0.93–1.08) | 0.90 (0.82–0.98) | 0.90 (0.83–0.98) | 0.91 (0.74–1.11) | |
| 6–12 | 0.81 (0.61–1.08) | 1.02 (0.95–1.08) | 0.96 (0.89–1.03) | 0.95 (0.89–1.02) | 0.95 (0.81–1.12) | |
| ≥ 12 | 0.91 (0.71–1.18) | 1.05 (0.99–1.12) | 0.97 (0.91–1.04) | 0.97 (0.91–1.03) | 0.95 (0.82–1.10) | |
Multivariable model including age, age at menarche, age at menopause, oral contraceptives, hormone replacement therapy, parity, breastfeeding, body mass index, smoking, alcohol consumption, regular exercise, hypertension, diabetes mellitus, hyperlipidemia, chronic kidney disease, and income. For the analysis of the reproductive span, a modified version of multivariable model – in which age at menarche and age at menopause were replaced by reproductive span – was used
Ref. reference group