Table 1. Characteristics of studies included in the dose-response meta-analysis.
| First author (ref), year, Country | No. of cases/cohort, age, follow-up | Energy-adjusted model (unit) | Exposure categories (Dietary assessment) | Risk estimates (95% CI) | Matched/adjusted factors |
|---|---|---|---|---|---|
| Prospective study | |||||
| Merritt et al [9], 2015, Europe | 1303/301,107 (25–70y), 11y | Residual (g/day) |
Quartile 4 vs. Quartile 1 Saturated fat Polyunsaturated fat Monounsaturated fat (Validated FFQ) |
Hazard ratio 0.95 (0.81–1.12) 0.87 (0.73–1.03) 0.80 (0.65–0.97) |
BMI, total energy intake, smoking status, age at menarche, OC use, parity, and a combined variable for menopausal status and postmenopausal hormone use and were stratified by age and study center |
| Merritt et al [9], 2015, USA | 1531/155,406 (30–55y), 25y | Residual (g/day) |
Quartile 4 vs. Quartile 1 Monounsaturated fat (Validated FFQ) |
Hazard ratio 0.95 (0.81–1.10) |
BMI, total energy intake, smoking status, age at menarche, OC use, parity, and menopausal status and postmenopausal hormone use and were stratified by age, cohort, and the 2-year questionnaire cycle |
| Cui et al [7], 2011, USA | 669/68,070 (30–55y), 21y | N/A (g/day) |
Quintile 5 vs. Quintile 1 Saturated fat Polyunsaturated fat (Validated FFQ) |
Relative Risk 0.90 (0.70–1.16) 1.05 (0.82–1.34) |
Age, follow-up period, total energy, smoking, OC use, postmenopausal hormone use, age at menopause, parity, age at menarche, hypertension, diabetes, BMI |
| Jain et al [16], 2000, Canada | 221/56,837 (40–59y), 9y | Residual (g/day) |
Quartile 4 vs. Quartile 1 Saturated fat (Validated FFQ) |
Relative Risk 0.70 (0.47–1.04) |
Total energy, age, BMI, ever smoked, used OC, used HRT, university education, livebirths, age at menarche |
| Case-control study | |||||
| Biel et al [10], 2011, Canada, PC-CS | 506/981 (mean, 58.7/58.3y) | Residual (g/day) |
Quartile 4 vs. Quartile 1 Saturated fat Monounsaturated fat Polyunsaturated fat (Validated FFQ) |
Odds Ratio 1.06 (0.76–1.49) 1.07 (0.77–1.48) 1.11 (0.81–1.54) |
Age, total energy intake, age at menarche, BMI, parity, educational level, hypertension history, OC use, HRT use combined with menopausal status, and alcohol consumption |
| Chandran et al [11], 2010, USA, PC-CS | 424/398 (mean, 61.6/64.3y) | N/A (g/day) |
Quartile 4 vs. Quartile 1 Saturated fat(FFQ) |
Odds Ratio 0.82 (0.43–1.58) |
Age, education, race, age at menarche, menopausal status and age at menopause for postmenopausalwomen, parity, OC use, HRT use, BMI, total calories intake, PA, smoking status, and alcohol |
| Yeh et al [12], 2009, USA, HC-CS | 541/541 (mean, 63.3/63.2y) | N/A (g/day) |
Quartile 4 vs. Quartile 1 Saturated fat Monounsaturated fat Polyunsaturated fat (FFQ) |
Odds Ratio 1.51 (0.84–2.68) 1.26 (0.71–2.23) 0.85 (0.51–1.41) |
Age, BMI, exogenous estrogen use, smoking, total menstrual months, total energy, total protein and carbohydrates intake |
| Lucenteforte et al [13], 2008, Italy, HC-CS | 454/908 (median, 60/61y) | Residual (g/day) |
Quintile 5 vs. Quintile 1 Saturated fat Monounsaturated fat Polyunsaturated fat (Validated FFQ) |
Odds Ratio 1.30 (0.90–2.00) 0.80 (0.60–1.20) 0.90 (0.60–1.40) |
Age, study centre, year of interview, education, PA, BMI, history of diabetes, age at menarche, age at menopause, parity, OC use, HRT use, total energy intake, according to the residual models |
| Salazar-Martinez et al [14], 2005, Mexico, HC-CS | 85/629 (mean, 51.7/57.1y) | Residual (g/day) |
Tertile 3 vs. Tertile 1 Saturated fat Monounsaturated fat Polyunsaturated fat (Validated FFQ) |
Odds Ratio 0.67 (0.29–1.53) 0.98 (0.41–2.43) 2.23 (0.98–5.05) |
Age, total energy intake, number of live births, BMI, PA, and diabetes |
| Littman et al [15], 2001, USA, PC-CS | 679/944 (45–74y) | Presented(g/1000 kcal/d) |
Quintile 5 vs. Quintile 1 Saturated fat (FFQ) |
Odds Ratio 1.60 (1.10–2.30) |
Age, county of residence, total energy intake, unopposed estrogen use, cigarette smoking, and BMI |
| McCann et al [17], 2000, USA, PC-CS | 232/639 (mean, 63.5/55.9y) | N/A (g/day) |
Quartile 4 vs. Quartile 1 Saturated fat Monounsaturated fat Polyunsaturated fat (Validated FFQ) |
Odds Ratio 1.10 (0.50–2.40) 0.90 (0.40–1.80) 1.00 (0.50–1.80) |
Age, education, BMI, diabetes, hypertension, pack-years cigarette smoking, age at menarche, parity, OC use, menopause status, postmenopausal estrogen use, and total energy intake |
| Jain et al [18], 2000, Canada, PC-CS | 552/562 (30–79y) | Residual (g/day) |
Quartile 4 vs. Quartile 1 Saturated fat Monounsaturated fat (Validated FFQ) |
Odds Ratio 1.22 (0.85–1.75) 1.08 (0.76–1.53) |
Total energy, age, body weight, ever smoked, history of diabetes, used OC, used HRT, university education, live births, age at menarche |
| Tzonou et al [19],* 1996, Greece, HC-CS | 145/298 (N/A) | N/A (g/day) |
Quartile 4 vs. Quartile 1 Saturated fat Monounsaturated fat Polyunsaturated fat (FFQ) |
Odds Ratio 0.75 (0.43–1.30) 0.67 (0.39–1.16) 1.13 (0.63–2.01) |
Age |
| Potischman et al [20], 1993, USA, PC-CS | 399/296 (mean, 59.1/58y) | N/A (g/day) |
Quartile 4 vs. Quartile 1 Saturated fat (FFQ) |
Odds Ratio 2.10 (1.20–3.70) |
Age, BMI, current smoking, years of education, number of births, ever OC use, ever menopausal estrogen use, and total calories intake |
BMI, body mass index; CI, confidence interval; HC-CS, hospital-based case-control study; PA, physical activity; PC-CS, population-based case-control study; N/A, not available; OC, oral contraceptive; FFQ, food frequency questionnaire.
*
Risk estimates were calculated from published data with EpiCalc 2000 software (version 1.02; Brixton Health).