TABLE 2.
HRs (95% CI) of type 2 diabetes risk according to quintile of red meat intake in the HPFS, NHS I, and NHS II1
| Frequency of consumption |
P-trend2 | HR (95% CI) for one serving/d | |||||
| Q1 | Q2 | Q3 | Q4 | Q5 | |||
| HPFS | |||||||
| Unprocessed red meat | |||||||
| Servings/d | 0.17 (0.08, 0.24)3 | 0.43 (0.37, 0.47) | 0.65 (0.57, 0.73) | 0.94 (0.86, 1.02) | 1.44 (1.29, 1.65) | ||
| Cases/person-years | 375/129,461 | 394/127,874 | 526/134,407 | 489/128,901 | 654/132,331 | ||
| Age-adjusted model | 1.00 | 1.07 (0.93, 1.24) | 1.41 (1.23, 1.60) | 1.33 (1.16, 1.52) | 1.79 (1.58, 2.04) | <0.001 | 1.38 (1.29, 1.48) |
| Multivariate model 1 | 1.00 | 1.03 (0.89, 1.19) | 1.31 (1.14, 1.50) | 1.23 (1.06, 1.42) | 1.65 (1.42, 1.91) | <0.001 | 1.33 (1.23, 1.44) |
| Multivariate model 2 | 1.00 | 0.95 (0.82, 1.09) | 1.14 (0.99, 1.31) | 1.05 (0.90, 1.21) | 1.29 (1.11, 1.50) | <0.001 | 1.16 (1.06, 1.26) |
| Processed red meat | |||||||
| Servings/d | 0.02 (0, 0.05) | 0.12 (0.09, 0.13) | 0.21 (0.20, 0.25) | 0.38 (0.33, 0.44) | 0.72 (0.60, 0.97) | ||
| Cases/person-years | 340/138,550 | 409/121,238 | 441/131,831 | 593/131,520 | 655/129,834 | ||
| Age-adjusted model | 1.00 | 1.38 (1.20, 1.60) | 1.40 (1.22, 1.62) | 1.88 (1.65, 2.15) | 2.08 (1.82, 2.37) | <0.001 | 1.55 (1.43, 1.68) |
| Multivariate model 1 | 1.00 | 1.32 (1.14, 1.53) | 1.32 (1.14, 1.52) | 1.75 (1.51, 2.01) | 1.96 (1.69, 2.27) | <0.001 | 1.47 (1.34, 1.62) |
| Multivariate model 2 | 1.00 | 1.18 (1.02, 1.37) | 1.12 (0.97, 1.30) | 1.44 (1.25, 1.66) | 1.55 (1.33, 1.79) | <0.001 | 1.34 (1.21, 1.48) |
| Total red meat | |||||||
| Servings/d | 0.25 (0.12, 0.36) | 0.60 (0.52, 0.69) | 0.94 (0.86, 1.03) | 1.34 (1.23, 1.46) | 2.02 (1.78, 2.43) | ||
| Cases/person-years | 346/129,959 | 398/131,492 | 488/130,148 | 545/130,744 | 661/130,631 | ||
| Age-adjusted model | 1.00 | 1.16 (1.01, 1.34) | 1.44 (1.25, 1.65) | 1.60 (1.39, 1.83) | 1.96 (1.72, 2.24) | <0.001 | 1.33 (1.27, 1.39) |
| Multivariate model 1 | 1.00 | 1.11 (0.96, 1.29) | 1.37 (1.18, 1.58) | 1.54 (1.32, 1.79) | 1.92 (1.64, 2.25) | <0.001 | 1.33 (1.25, 1.41) |
| Multivariate model 2 | 1.00 | 1.01 (0.87, 1.17) | 1.17 (1.01, 1.35) | 1.25 (1.08, 1.45) | 1.44 (1.23, 1.68) | <0.001 | 1.19 (1.12, 1.27) |
| NHS I | |||||||
| Unprocessed red meat | |||||||
| Servings/d | 0.37 (0.28, 0.45) | 0.61 (0.56, 0.67) | 0.84 (0.75, 0.98) | 1.09 (0.97, 1.26) | 1.57 (1.33, 1.95) | ||
| Cases/person-years | 1278/404,906 | 1534/402,338 | 1592/403,148 | 1793/394,652 | 2056/409,128 | ||
| Age-adjusted model | 1.00 | 1.23 (1.14, 1.32) | 1.28 (1.19, 1.37) | 1.46 (1.36, 1.57) | 1.64 (1.53, 1.75) | <0.001 | 1.29 (1.24, 1.34) |
| Multivariate model 1 | 1.00 | 1.17 (1.08, 1.26) | 1.18 (1.10, 1.28) | 1.29 (1.19, 1.39) | 1.39 (1.28, 1.50) | <0.001 | 1.15 (1.10, 1.20) |
| Multivariate model 2 | 1.00 | 1.10 (1.02, 1.19) | 1.10 (1.02, 1.18) | 1.16 (1.08, 1.25) | 1.23 (1.14, 1.33) | <0.001 | 1.09 (1.04, 1.14) |
| Processed red meat | |||||||
| Servings/d | 0.05 (0.02, 0.07) | 0.14 (0.13, 0.16) | 0.23 (0.21, 0.27) | 0.35 (0.32, 0.42) | 0.64 (0.52, 0.83) | ||
| Cases/person-years | 1174/403,239 | 1426/381,686 | 1632/420,660 | 1885/404,142 | 2136/404,445 | ||
| Age-adjusted model | 1.00 | 1.26 (1.17, 1.36) | 1.42 (1.32, 1.53) | 1.65 (1.53, 1.77) | 1.93 (1.80, 2.08) | <0.001 | 1.85 (1.74, 1.97) |
| Multivariate model 1 | 1.00 | 1.19 (1.10, 1.29) | 1.32 (1.22, 1.42) | 1.46 (1.36, 1.58) | 1.60 (1.48, 1.72) | <0.001 | 1.54 (1.44, 1.65) |
| Multivariate model 2 | 1.00 | 1.08 (1.00, 1.17) | 1.15 (1.06, 1.24) | 1.23 (1.14, 1.33) | 1.30 (1.20, 1.40) | <0.001 | 1.30 (1.21, 1.41) |
| Total red meat | |||||||
| Servings/d | 0.50 (0.36, 0.61) | 0.83 (0.75, 0.95) | 1.12 (0.99, 1.30) | 1.44 (1.27, 1.68) | 2.07 (1.75, 2.55) | ||
| Cases/person-years | 1212/401,534 | 1444/405,038 | 1586/401,953 | 1863/403,092 | 2148/402,555 | ||
| Age-adjusted model | 1.00 | 1.22 (1.13, 1.31) | 1.35 (1.25, 1.46) | 1.59 (1.48, 1.71) | 1.84 (1.71, 1.97) | <0.001 | 1.32 (1.28, 1.36) |
| Multivariate model 1 | 1.00 | 1.16 (1.07, 1.25) | 1.25 (1.16, 1.35) | 1.42 (1.31, 1.54) | 1.55 (1.43, 1.68) | <0.001 | 1.21 (1.16, 1.25) |
| Multivariate model 2 | 1.00 | 1.08 (1.00, 1.17) | 1.13 (1.04, 1.22) | 1.25 (1.15, 1.35) | 1.31 (1.21, 1.42) | <0.001 | 1.13 (1.08, 1.17) |
| NHS II | |||||||
| Unprocessed red meat | |||||||
| Servings/d | 0.17 (0.07, 0.25) | 0.43 (0.37, 0.47) | 0.61 (0.56, 0.66) | 0.84 (0.76, 0.92) | 1.29 (1.12, 1.53) | ||
| Cases/person-years | 368/271,759 | 462/266,716 | 562/278,014 | 690/276,425 | 986/273,261 | ||
| Age-adjusted model | 1.00 | 1.28 (1.12, 1.47) | 1.54 (1.35, 1.76) | 1.89 (1.66, 2.14) | 2.70 (2.39, 3.04) | <0.001 | 1.88 (1.77, 1.99) |
| Multivariate model 1 | 1.00 | 1.17 (1.01, 1.34) | 1.31 (1.14, 1.50) | 1.39 (1.21, 1.59) | 1.69 (1.47, 1.93) | <0.001 | 1.36 (1.26, 1.47) |
| Multivariate model 2 | 1.00 | 1.01 (0.88, 1.16) | 1.13 (0.99, 1.29) | 1.12 (0.98, 1.28) | 1.27 (1.11, 1.46) | <0.001 | 1.18 (1.09, 1.28) |
| Processed red meat | |||||||
| Servings/d | 0 (0, 0.03) | 0.07 (0.07, 0.10) | 0.14 (0.13, 0.17) | 0.25 (0.21, 0.28) | 0.49 (0.39, 0.64) | ||
| Cases/person-years | 389/273,513 | 464/254,002 | 582/296,610 | 626/262,102 | 1007/279,949 | ||
| Age-adjusted model | 1.00 | 1.29 (1.13, 1.48) | 1.54 (1.35, 1.75) | 1.78 (1.57, 2.02) | 2.81 (2.50, 3.16) | <0.001 | 2.53 (2.34, 2.73) |
| Multivariate model 1 | 1.00 | 1.10 (0.96, 1.26) | 1.24 (1.08, 1.41) | 1.32 (1.16, 1.51) | 1.72 (1.52, 1.96) | <0.001 | 1.76 (1.58, 1.96) |
| Multivariate model 2 | 1.00 | 0.93 (0.81, 1.06) | 1.00 (0.88, 1.14) | 1.02 (0.89, 1.16) | 1.21 (1.07, 1.38) | <0.001 | 1.37 (1.21, 1.55) |
| Total red meat | |||||||
| Servings/d | 0.35 (0.21, 0.45) | 0.67 (0.60, 0.73) | 0.92 (0.85, 1.00) | 1.23 (1.13, 1.34) | 1.80 (1.58, 2.13) | ||
| Cases/person-years | 324/271,508 | 443/272,488 | 564/273,770 | 678/273,938 | 1059/274,471 | ||
| Age-adjusted model | 1.00 | 1.40 (1.21, 1.61) | 1.79 (1.56, 2.05) | 2.16 (1.89, 2.46) | 3.38 (2.98, 3.83) | <0.001 | 1.82 (1.74, 1.91) |
| Multivariate model 1 | 1.00 | 1.23 (1.07, 1.42) | 1.46 (1.27, 1.68) | 1.58 (1.37, 1.81) | 2.07 (1.80, 2.38) | <0.001 | 1.42 (1.34, 1.50) |
| Multivariate model 2 | 1.00 | 1.05 (0.91, 1.21) | 1.16 (1.01, 1.34) | 1.17 (1.02, 1.35) | 1.37 (1.19, 1.57) | <0.001 | 1.18 (1.11, 1.26) |
| Pooled results4 | |||||||
| Unprocessed red meat | 1.00 | 1.06 (1.00, 1.12) | 1.11 (1.05, 1.18) | 1.13 (1.07, 1.20) | 1.25 (1.17, 1.33) | <0.001 | 1.12 (1.08, 1.16) |
| Processed red meat | 1.00 | 1.06 (1.00, 1.13) | 1.11 (1.05, 1.18) | 1.22 (1.15, 1.29) | 1.32 (1.24, 1.40) | <0.001 | 1.32 (1.25, 1.40) |
| Total red meat | 1.00 | 1.06 (1.00, 1.13) | 1.14 (1.07, 1.21) | 1.23 (1.16, 1.31) | 1.34 (1.26, 1.43) | <0.001 | 1.14 (1.10, 1.18) |
One serving of unprocessed red meat equals 85 g (3 ounces) pork, beef, or lamb; one serving of processed red meat equals 28 g bacon or 45 g hot dog, sausage, salami, bologna, or other processed red meats. Multivariate model 1 was adjusted for age (continuous), alcohol consumption (0, 0.1–4.9, 5.0–14.9, ≥15 g/d), physical activity level (<3, 3–8.9, 9–17.9, 18–26.9, ≥27 metabolic equivalent task hours/wk), smoking status (never; past; current: 1–14, 15–24, or >24 cigarettes/d), race (white, nonwhite), menopausal status and hormone use in women (premenopausal, postmenopausal never users, postmenopausal past users, postmenopausal current users), family history of diabetes, history of hypertension and hypercholesterolemia, quintiles of total calories, and dietary score. Multivariate model 2 was the same as model 1 with the addition of a BMI category (in kg/m2; <23, 23–24.9, 25–29.9, 30–34.9, ≥35). HPFS, Health Professionals Follow-Up Study; NHS, Nurses’ Health Study; Q, quintile.
P-trend was calculated by assigning median values to each quintile and was treated as continuous variable.
Median; interquartile range in parentheses (all such values).
Results from multivariate model 2 were combined with the use of a fixed-effects model given that the Egger's tests for heterogeneity were not significant for all 3 meta-analyses (all P values > 0.15).