Table 1 Characteristics of the included studies about the association of dietary protein intake on prostate cancer risk
From: Association between dietary protein intake and prostate cancer risk: evidence from a meta-analysis
Study, year | Design | Age | Participants; cases | Country | Follow-up duration | Protein type | Category | RR (95%CI) | Adjustment |
|---|---|---|---|---|---|---|---|---|---|
Allen NE, 2008 | Cohort | 60.3 ± 6.7 | 142,251; 2727 | European countries | 8.7 | Total protein | Total protein | Total protein | Adjusted for education, marital status, height, weight, and energy intake |
Animal | 80 g/day | 1 | |||||||
Vegetable | 90 g/day | 0.93 (0.82–1.05) | |||||||
98 g/day | 0.90 (0.78–1.04) | ||||||||
105 g/day | 1.00 (0.85–1.18) | ||||||||
121 g/day | 1.17 (0.96–1.44) | ||||||||
Animal | Animal | ||||||||
47 g/day | 1 | ||||||||
59 g/day | 0.88 (0.77–1.00) | ||||||||
64 g/day | 0.84 (0.73–0.97) | ||||||||
69 g/day | 0.99 (0.86–1.15) | ||||||||
80 g/day | 0.97 (0.81–1.15) | ||||||||
Vegetable | Vegetable | ||||||||
29 g/day | 1 | ||||||||
33 g/day | 1.09 (0.96–1.22) | ||||||||
36 g/day | 1.04 (0.91–1.19) | ||||||||
38 g/day | 1.08 (0.93–1.26) | ||||||||
47 g/day | 1.01 (0.82–1.23) | ||||||||
Andersson SO, 1996 | Case-control | 70.7 ± 5.9 | 1056; 524 | Sweden | NA | Total protein | Quartile 1 | 1 | Adjusted for age and energy |
Quartile 2 | 0.90 (0.63–1.28) | ||||||||
Quartile 3 | 1.10 (0.78–1.55) | ||||||||
Quartile 4 | 1.07 (0.76–1.50) | ||||||||
Berndt SI, 2002 | Cohort | 46–92 | 454; 69 | USA | 3.5 | Animal | 36.8 g/day | 1 | Adjusted for age and energy |
48.0 g/day | 0.94 (0.49–1.82) | ||||||||
62.8 g/day | 1.06 (0.56–2.01) | ||||||||
Chan JM, 2000 | Cohort | 50–69 | 27,062; 184 | Finland | 8 | Total protein | 82 g/day | 1 | Adjusted for supplementation group, education, and quintiles of age, body mass index, energy, and number of years as a smoker |
94 g/day | 0.9 (0.6–1.3) | ||||||||
102 g/day | 0.6 (0.4–1.0) | ||||||||
107 g/day | 0.8 (0.5–1.3) | ||||||||
117 g/day | 1.0 (0.7–1.6) | ||||||||
Deneo-Pellegrini H, 1999 | Case-control | 40–89 | 408; 175 | Uruguay | NA | Total protein | Quartile 1 | 1 | Adjusted for age, residence, urban/rural status, education, family history of prostate cancer, body mass index and total energy intake |
Quartile 2 | 1.1 (0.6–1.0) | ||||||||
Quartile 3 | 1.7 (0.9–1.3) | ||||||||
Quartile 4 | 1.0 (0.6–1.8) | ||||||||
Kristal AR, 2010 | RCT | 63.6 ± 5.6 | 9559; 1703 | USA and Canada | NA | Total protein | Quartile 1 | 1 | Adjusted for age, race/ethnicity, treatment arm, and body mass index |
Quartile 2 | 1.00 (0.86–1.17) | ||||||||
Quartile 3 | 0.96 (0.82–1.12) | ||||||||
Quartile 4 | 0.93 (0.79–1.08) | ||||||||
Lane JA, 2017 | Cohort | 63.0 ± 6.5 | 5245; 1717 | UK | 13.3 | Total protein | Quartile 1 | 1 | Adjusted for age, BMI, socioeconomic, smoking and marital status, diabetes and energy intake |
Quartile 2 | 1.00 (0.82–1.23) | ||||||||
Quartile 3 | 1.16 (0.95–1.42) | ||||||||
Quartile 4 | 1.02 (0.83–1.25) | ||||||||
Quartile 5 | 1.03 (0.83–1.29) | ||||||||
Mills PK, 1989 | Cohort | 74 | 14,000; 180 | USA | 6 | Vegetable | < 1 serving/week | 1 | Adjusted for age |
1–4 serving/week | 0.83 (0.59–1.16) | ||||||||
> 4 serving/week | 0.67 (0.40–1.12) | ||||||||
Schuurman AG, 1999 | Cohort | 63.9 ± 3.8 | 58,279; 642 | Netherlands | 6.3 | Total protein | Total protein | Total protein | Adjusted for age, family history of prostate cancer, socioeconomic status and total energy intake |
Animal | 62 g/day | 1 | |||||||
Vegetable | 69 g/day | 1.04 (0.76–1.43) | |||||||
75 g/day | 1.12 (0.82–1.53) | ||||||||
81 g/day | 1.35 (0.98–1.84) | ||||||||
90 g/day | 1.10 (0.81–1.51) | ||||||||
Animal | Animal | ||||||||
34 g/day | 1 | ||||||||
42 g/day | 1.29 (0.92–1.81) | ||||||||
47 g/day | 1.16 (0.80–1.68) | ||||||||
53 g/day | 1.52 (1.01–2.30) | ||||||||
64 g/day | 1.32 (0.76–2.29) | ||||||||
Vegetable | Vegetable | ||||||||
22 g/day | 1 | ||||||||
25 g/day | 0.86 (0.63–1.17) | ||||||||
27 g/day | 1.00 (0.74–1.36) | ||||||||
30 g/day | 0.83 (0.61–1.14) | ||||||||
35 g/day | 0.90 (0.66–1.23) | ||||||||
Severson, RK 1989 | Cohort | NA | 7999; 174 | Japanese | 18 | Total protein | 0–74.9 g | 1 | Adjusted for age |
75.0–99.9 g | 1.54 (1.07–2.22) | ||||||||
100.0+ g | 1.13 (0.76–1.67) | ||||||||
Smit E, 2007 | Cohort | 45–64 | 9777; 167 | Puerto Rico | 12 | Total protein | Total protein | Total protein | Adjusted for age, education, body mass index, living, physical activity, smoking and residual energy intake. Calories not adjusted for energy intake |
Animal | ≤ 61 g | 1 | |||||||
Vegetable | 62–82 g | 0.94 (0.60–1.48) | |||||||
83–103 g | 1.02 (0.64–1.63) | ||||||||
≥ 104 g | 1.32 (0.81–2.17) | ||||||||
Animal | Animal | ||||||||
≤ 13 g | 1 | ||||||||
14–23 g | 0.78 (0.49–1.24) | ||||||||
24–40 g | 0.91 (0.55–1.51) | ||||||||
≥ 41 g | 1.01 (0.52–1.96) | ||||||||
Vegetable | Vegetable | ||||||||
≤ 16 g | 1 | ||||||||
17–23 g | 1.27 (0.82–1.96) | ||||||||
24–31 g | 1.07 (0.66–1.75) | ||||||||
≥ 32 g | 1.19 (0.66–2.13) | ||||||||
Tsilidis KK, 2013 | Case-control | 67.3 ± 5.4 | 10,155; 5221 | European countries | NA | Total protein | Total protein | Total protein | Adjusted for continuous age at blood draw, continuous body mass index and energy consumption |
Animal | Tertile 1 | 1 | |||||||
Vegetable | Tertile 2 | 0.96 (0.87–1.06) | |||||||
Tertile 3 | 0.95 (0.86–1.05) | ||||||||
Animal | Animal | ||||||||
Tertile 1 | 1 | ||||||||
Tertile 2 | 1.05 (0.95–1.16) | ||||||||
Tertile 3 | 1.00 (0.90–1.11) | ||||||||
Vegetable | Vegetable | ||||||||
Tertile 1 | 1 | ||||||||
Tertile 2 | 0.98 (0.89–1.09) | ||||||||
Tertile 3 | 1.00 (0.90–1.11) |