Table 4.

Interaction of daily intake of glycemic index, glycemic load, fructose, and glucose (quintile, Q) with body mass index, physical activity, and smoking in modifying risks of pancreatic cancer

CasesRR (95%CI)*
P, P
Q1Q2Q3Q4Q5
Glycemic index
    BMI <30 kg/m29101.001.06 (0.86-1.32)0.92 (0.74-1.14)0.99 (0.80-1.23)1.14 (0.93-1.41)
    BMI ≥ 30 kg/m22141.07 (0.75-1.52)1.19 (0.86-1.65)1.06 (0.76-1.48)0.85 (0.60-1.22)0.93 (0.66-1.30)0.99, 0.44
    Less physical activity§6211.001.43 (0.99-2.07)1.08 (0.74-1.58)1.23 (0.85-1.76)1.24 (0.88-1.76)
    More physical activity§5301.18 (0.85-1.65)1.19 (0.85-1.65)1.11 (0.79-1.54)1.02 (0.72-1.42)1.24 (0.89-1.73)0.57, 0.22
    Never smokers3131.001.23 (0.87-1.72)0.92 (0.64-1.32)0.87 (0.60-1.27)1.17 (0.82-1.67)
    Ever smokers7831.46 (0.89-2.40)1.51 (0.92-2.47)1.47 (0.90-2.41)1.44 (0.88-2.35)1.58 (0.97-2.56)0.75, 0.65
Glycemic load
    BMI <30 kg/m29101.000.83 (0.66-1.03)1.03 (0.82-1.29)1.05 (0.83-1.34)0.94 (0.72-1.23)
    BMI ≥ 30 kg/m22141.05 (0.79-1.40)0.96 (0.69-1.33)0.80 (0.55-1.16)1.02 (0.71-1.47)0.92 (0.60-1.40)0.96, 0.57
    Less physical activity§6211.000.97 (0.71-1.33)1.12 (0.82-1.54)1.16 (0.83-1.61)0.90 (0.62-1.30)
    More physical activity§5301.07 (0.83-1.37)0.86 (0.65-1.13)0.94 (0.71-1.25)1.04 (0.78-1.39)0.99 (0.72-1.36)0.54, 0.56
    Never smokers3131.000.99 (0.65-1.51)1.33 (0.90-1.98)1.21 (0.80-1.82)1.18 (0.77-1.80)
    Ever smokers7831.85 (1.10-3.09)1.53 (0.90-2.58)1.62 (0.95-2.76)1.79 (1.04-3.05)1.55 (0.90-2.69)0.99, 0.39
Fructose (g/1,000 kcal)
    BMI <30 kg/m29101.001.05 (0.85-1.30)1.16 (0.94-1.44)1.32 (1.07-1.64)1.28 (1.02-1.62)
    BMI ≥ 30 kg/m22141.12 (0.83-1.51)0.97 (0.68-1.37)1.17 (0.83-1.64)0.94 (0.63-1.39)1.49 (1.06-2.10)0.18, 0.26
    Less physical activity§6211.000.94 (0.69-1.28)1.05 (0.77-1.44)1.40 (1.03-1.89)1.15 (0.83-1.60)
    More physical activity§5300.90 (0.70-1.17)0.98 (0.76-1.27)1.08 (0.84-1.40)1.06 (0.82-1.38)1.22 (0.93-1.60)0.53, 0.98
    Never smokers3131.001.06 (0.72-1.54)0.88 (0.60-1.30)0.97 (0.67-1.42)1.06 (0.73-1.56)
    Ever smokers7831.28 (0.77-2.10)1.24 (0.74-2.05)1.55 (0.94-1.58)1.66 (1.00-2.77)1.63 (0.97-2.73)0.02, 0.40
Glucose (g/1,000 kcal)
    BMI <30 kg/m29101.001.12 (0.90-1.37)1.32 (1.07-1.63)1.22 (0.97-1.52)1.35 (1.07-1.71)
    BMI ≥ 30 kg/m22141.12 (0.83-1.52)0.87 (0.61-1.26)1.48 (1.08-2.03)0.85 (0.56-1.29)1.55 (1.10-2.18)0.19, 0.15
    Less physical activity§6211.001.16 (0.86-1.58)1.19 (0.87-1.64)1.38 (1.00-1.89)1.28 (0.92-1.78)
    More physical activity§5301.00 (0.77-1.29)1.01 (0.77-1.31)1.35 (1.04-1.75)1.02 (0.77-1.34)1.32 (1.00-1.74)0.59, 0.88
    Never smokers3131.001.00 (0.67-1.47)1.09 (0.76-1.58)1.09 (0.75-1.58)1.04 (0.71-1.53)
    Ever smokers7831.32 (0.81-2.71)1.35 (0.82-2.24)1.78 (1.08-2.94)1.43 (0.86-2.39)1.83 (1.10-3.05)0.03, 0.56
  • NOTE: All Cox proportional hazard models were run using age as underlying time metric.

  • * Adjusted for age, total energy intake (log-transformed), alcohol use (5-category drink level), energy-adjusted saturated fat and red meat intake, smoking variables, and BMI (categorical). A smoking variable with finer categories was generated in order to account for its confounding effect: never smokers, quit ≥10 y and smoked <20 cigarette/d, quit ≥10 y and smoked ≥20 cigarette/d, quit 5-9 y and smoked <20 cigarette/d, quit 5-9 y and smoked ≥20 cigarette/d, quit 1-4 y and smoked <20 cigarette/d, quit 1-4 y and smoked ≥20 cigarette/d, current smokers with <20 cigarette/d, current smokers with ≥20 cigarette/d, and a missing category.

  • Linear trend was tested using the Wald test by treating the ordinal variables as the continuous variable.

  • P values for likelihood ratio test for interaction term.

  • § Less physical activity is defined as physical activity at least 20 minutes that caused increases in breathing or heart rate for less than 3-4 times per week. More physical activity is physical activity at least 20 minutes that caused increases in breathing or heart rate for 3-4 times or more per week.