Table 3 Adjusted relative risks of cholecystectomy according to waist‐hip ratio among US women in the Nurses' Health Study.
| Waist‐hip ratio category | |||||||
|---|---|---|---|---|---|---|---|
| <0.70 | 0.70–<0.74 | 0.74–<0.78 | 0.78–<0.82 | 0.82–<0.86 | ⩾0.86 | p for trend | |
| Cases | 187 | 516 | 793 | 682 | 546 | 473 | – |
| Person years | 44 622 | 110 880 | 137 123 | 104 898 | 63 863 | 52 898 | – |
| Model 1: age adjusted (RR) | 1.00 | 1.10 (0.93–1.30) | 1.31 (1.12–1.54) | 1.50 (1.27–1.77) | 1.93 (1.63–2.29) | 1.99 (1.66–2.37) | <0.0001 |
| Model 2: multivariable (RR) | 1.00 | 1.09 (0.92–1.29) | 1.32 (1.13–1.55) | 1.46 (1.24–1.72) | 1.89 (1.59–2.24) | 1.97 (1.66–2.35) | <0.0001 |
| Model 3: multivariable (RR) | 1.00 | 1.11 (0.94–1.31) | 1.32 (1.13–1.55) | 1.44 (1.22–1.70) | 1.85 (1.56–2.20) | 1.89 (1.59–2.25) | <0.0001 |
| Model 4: multivariable (RR) | 1.00 | 1.12 (0.95–1.33) | 1.23 (1.05–1.45) | 1.23 (1.04–1.45) | 1.48 (1.25–1.76) | 1.39 (1.16–1.66) | <0.0001 |
RR, relative risk (95% confidence interval).
Model 1: RR = relative risk adjusting for age (five year categories).
Model 2: RR = relative risk adjusting for age (one year categories), time period (1986–88, 1988–90, 1990–92, 1992–94, 1994–96, 1996–98, 1998–2000), parity (0, 1, 2–3, ⩾4 births), oral contraceptive use (ever, never), hormone replacement therapy (premenopausal, postmenopausal without hormone replacement therapy, postmenopausal with past hormone replacement therapy, and postmenopausal with current hormone replacement therapy), physical activity (quintiles), pack years of smoking (0, 1–9, 10–24, 25–44, 45–64, ⩾65), thiazide diuretics (yes or no), non‐steroidal anti‐inflammatory drugs (0, 1–6, ⩾7 times per week, and dose unknown), intake of total energy (quintiles), energy adjusted dietary fibre (quintiles), energy adjusted carbohydrates (quintiles), energy adjusted polyunsaturated fat (quintiles), energy adjusted monounsaturated fat (quintiles), energy adjusted saturated fat (quintiles), energy adjusted trans fat (quintiles), alcohol (0, 0.1–4.9, 5.0–14.9, 15.0–29.9, ⩾30.0 g/day), and coffee (0, 1, 2–3, 4+ cups per day).
Model 3: model 2 with additional adjustment for weight change during the past two years (five categories).
Model 4: model 3 with additional adjustment for body mass index (10 categories).