Table 2.

Medians (interquartile ranges) of serum adiponectin, leptin, C-peptide, and homocysteine concentrations at T1, by characteristics of participants at T1 in the control arm of the PPT (n = 627)

T1 characteristicsnAdiponectin (ng/mL)P*nLeptin (ng/mL)P*nC-peptide (ng/mL)P*nHomocysteine (μmol/L)P*
Median (IQR)Median (IQR)Median (IQR)Median (IQR)
Total6273.16 (1.94-5.10)6279.31 (4.63-17.4)6231.37 (0.98-1.80)62513.0 (10.8-15.7)
Sex
    Female2433.48 (2.19-6.03)24319.3 (10.4-21.2)2411.20 (0.90-1.64)24211.5 (9.86-14.0)
    Male3843.01 (1.80-4.67)0.0043846.31 (3.40-10.5)<0.00013821.45 (1.09-1.90)<0.000138313.9 (11.8-16.4)<0.0001
Age quartiles (y)
    Q1 (36-56)1743.02 (1.56-4.51)1747.41 (4.23-18.9)1741.20 (0.92-1.69)17411.9 (10.3-14.7)
    Q2 (57-64)1603.16 (1.77-5.09)1609.02 (5.04-17.1)1591.41 (0.98-1.89)15913.3 (10.9-15.8)
    Q3 (65-70)1392.99 (2.06-5.08)1399.91 (5.75-17.8)1381.42 (1.13-1.89)13814.1 (11.5-16.1)
    Q4 (71-87)1543.58 (2.29-5.82)0.041549.40 (4.04-17.2)0.641521.38 (1.04-1.78)0.0115413.3 (11.2-16.0)0.0004
BMI (kg/m2)
    <251583.37 (2.15-6.33)1585.58 (2.45-10.4)1570.98 (0.78-1.25)15712.0 (10.3-15.1)
    25-29.93203.10 (1.87-4.99)3208.15 (4.88-17.0)3181.41 (1.08-1.81)31913.3 (10.9-16.0)
    ≥301493.03 (1.80-4.84)0.1114915.6 (9.91-28.4)<0.00011481.69 (1.32-2.06)<0.000114913.6 (11.5-15.4)0.003
Physical activity quartiles (h/wk)
    Q1 (0-3.3)1563.16 (1.93-4.75)15614.4 (6.82-25.6)1541.50 (1.14-2.01)15613.2 (11.0-16.1)
    Q2 (3.4-6.7)1563.19 (1.96-5.09)1569.26 (4.88-18.2)1551.37 (0.96-1.74)15512.8 (10.8-15.2)
    Q3 (6.8-12.0)1563.01 (1.75-4.77)1569.35 (4.38-15.7)1561.27 (0.96-1.68)15612.2 (10.3-15.5)
    Q4 (12.1-91.2)1563.39 (2.06-5.84)0.181566.60 (3.46-11.8)<0.00011551.34 (0.89-1.74)0.000515513.6 (11.4-15.8)0.12
Race
    Caucasian5763.21 (1.96-5.14)5769.14 (4.68-17.2)5721.37 (0.99-1.79)57413.0 (10.8-15.7)
    Other512.68 (1.78-3.60)0.045110.7 (4.17-20.7)0.45511.41 (0.90-1.90)0.945112.9 (10.9-15.9)0.91
NSAID use
    No3893.16 (1.86-5.08)3898.59 (4.70-17.0)3881.37 (0.98-1.83)38813.0 (10.9-15.7)
    Yes2353.21 (2.07-5.12)0.752359.76 (4.53-19.8)0.342321.38 (0.98-1.74)0.7323413.0 (10.7-15.6)0.73
Dietary intake
    Fat (% kcal)
        Q1 (15.2-28.3)1583.37 (2.10-5.83)1587.41 (3.88-15.8)1571.26 (0.98-1.67)15712.7 (10.4-15.4)
        Q2 (28.4-34.1)1552.84 (1.56-4.98)15510.5 (4.48-19.0)1531.29 (0.90-1.73)15412.6 (10.5-15.3)
        Q3 (34.2-39.3)1573.13 (1.85-4.84)1578.43 (5.18-17.8)1561.42 (1.09-1.81)15713.2 (11.2-15.6)
        Q4 (39.4-54.8)1563.12 (2.08-4.91)0.1415610.0 (4.94-18.0)0.051561.44 (1.09-1.95)0.000815613.5 (11.2-16.1)0.01
    Fiber (g/1,000 kcal)
        Q1 (2.21-7.34)1573.02 (2.02-4.60)1579.06 (3.98-15.1)1571.44 (1.08-1.97)15713.9 (12.0-17.1)
        Q2 (7.35-9.55)1563.35 (2.26-4.95)15610.2 (5.32-21.9)1551.41 (1.01-1.77)15612.9 (10.9-15.2)
        Q3 (9.56-12.5)1573.00 (1.76-5.34)1579.05 (5.18-17.3)1571.28 (0.93-1.73)15712.5 (10.6-14.9)
        Q4 (12.6-28.5)1563.28 (1.77-5.98)0.661567.63 (4.18-15.9)0.021531.27 (0.94-1.70)0.00315412.6 (10.3-15.4)0.009
    Fruits and vegetables (servings/1,000 kcal)
        Q1 (0.33-1.45)1573.17 (1.99-4.68)1578.17 (4.02-14.7)1561.45 (1.12-1.96)15713.9 (11.8-16.4)
        Q2 (1.46-2.05)1563.08 (2.02-5.04)1567.61 (3.84-16.4)1561.38 (0.98-1.83)15613.5 (11.2-16.2)
        Q3 (2.06-2.72)1573.15 (1.92-4.74)1579.67 (5.75-19.6)1561.38 (0.96-1.76)15712.3 (10.4-15.0)
        Q4 (2.73-5.50)1563.30 (1.79-6.02)0.8415610.4 (4.84-19.6)0.241541.23 (0.92-1.61)0.00215412.0 (10.3-14.8)0.002
    Flavonols (mg/1,000 kcal)
        Q1 (1.14-6.07)1573.12 (2.01-4.68)1579.71 (4.70-16.3)1561.47 (1.12-1.96)15613.5 (11.1-15.8)
        Q2 (6.08-8.63)1563.22 (1.97-5.32)1568.83 (3.86-19.1)1551.35 (0.97-1.79)15613.3 (11.5-16.2)
        Q3 (8.64-12.4)1572.85 (1.57-4.60)1578.72 (4.29-19.0)1571.41 (1.04-1.78)15713.0 (10.9-15.7)
        Q4 (12.5-28.5)1563.32 (2.06-6.04)0.361569.01 (5.11-17.3)0.111541.21 (0.89-1.53)0.000715512.1 (10.2-14.6)0.006
    Dry beans (g/1,000 kcal)
        Q1 (0-1.56)1572.99 (1.99-4.65)1579.38 (4.69-15.9)1561.40 (0.97-1.91)15713.7 (11.3-16.0)
        Q2 (1.57-3.77)1563.33 (1.96-5.22)1569.34 (4.43-18.6)1551.39 (0.96-1.82)15513.2 (11.0-16.2)
        Q3 (3.78-7.90)1573.24 (1.84-4.93)1579.38 (5.18-18.9)1561.37 (1.08-1.73)15712.5 (10.8-14.9)
        Q4 (7.91-58.5)1563.13 (2.03-5.82)0.331568.38 (4.11-17.3)0.351551.25 (0.97-1.76)0.4915513.0 (10.3-15.3)0.03
  • *P values for differences in medians were calculated using Wilcoxon rank-sum test (two-group comparison) and Kruskal-Wallis test (comparison of more than two groups). P values for trend of dietary intake characteristics were calculated using a multiple regression model adjusting for the baseline characteristics of age (in quartiles: <56, 56-63, 64-69, >69 y), sex, BMI (<25, 25.0-29.9, ≥30 kg/m2), and regular NSAID use.

  • Physical activity was defined as self-reported time typically spent for any type of moderate or vigorous physical activity in hours per week.

  • Regular NSAID use was defined as taking medication ≥1 monthly.

  • *P values for differences in medians were calculated using Wilcoxon rank-sum test (two-group comparison) and Kruskal-Wallis test (comparison of more than two groups). P values for trend of dietary intake characteristics were calculated using a multiple regression model adjusting for the baseline characteristics of age (in quartiles: <56, 56-63, 64-69, >69 y), sex, BMI (<25, 25.0-29.9, ≥30 kg/m2), and regular NSAID use.

  • Physical activity was defined as self-reported time typically spent for any type of moderate or vigorous physical activity in hours per week.

  • Regular NSAID use was defined as taking medication ≥1 monthly.